content: package org.json;
  
  /*
  Public Domain.
  */
  
  import java.io.Closeable;
  import java.io.IOException;
  import java.io.Writer;
  import java.lang.annotation.Annotation;
  import java.lang.reflect.Field;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.lang.reflect.Modifier;
  import java.math.BigDecimal;
  import java.math.BigInteger;
  import java.util.*;
  import java.util.Map.Entry;
  import java.util.regex.Pattern;
  
  /**
   * A JSONObject is an unordered collection of name/value pairs. Its external
   * form is a string wrapped in curly braces with colons between the names and
   * values, and commas between the values and names. The internal form is an
   * object having <code>get</code> and <code>opt</code> methods for accessing
   * the values by name, and <code>put</code> methods for adding or replacing
   * values by name. The values can be any of these types: <code>Boolean</code>,
   * <code>JSONArray</code>, <code>JSONObject</code>, <code>Number</code>,
   * <code>String</code>, or the <code>JSONObject.NULL</code> object. A
   * JSONObject constructor can be used to convert an external form JSON text
   * into an internal form whose values can be retrieved with the
   * <code>get</code> and <code>opt</code> methods, or to convert values into a
   * JSON text using the <code>put</code> and <code>toString</code> methods. A
   * <code>get</code> method returns a value if one can be found, and throws an
   * exception if one cannot be found. An <code>opt</code> method returns a
   * default value instead of throwing an exception, and so is useful for
   * obtaining optional values.
   * <p>
   * The generic <code>get()</code> and <code>opt()</code> methods return an
   * object, which you can cast or query for type. There are also typed
   * <code>get</code> and <code>opt</code> methods that do type checking and type
   * coercion for you. The opt methods differ from the get methods in that they
   * do not throw. Instead, they return a specified value, such as null.
   * <p>
   * The <code>put</code> methods add or replace values in an object. For
   * example,
   *
   * <pre>
   * myString = new JSONObject()
   *         .put(&quot;JSON&quot;, &quot;Hello, World!&quot;).toString();
   * </pre>
   *
   * produces the string <code>{"JSON": "Hello, World"}</code>.
   * <p>
   * The texts produced by the <code>toString</code> methods strictly conform to
   * the JSON syntax rules. The constructors are more forgiving in the texts they
   * will accept:
   * <ul>
   * <li>An extra <code>,</code>&nbsp;<small>(comma)</small> may appear just
   * before the closing brace.</li>
   * <li>Strings may be quoted with <code>'</code>&nbsp;<small>(single
   * quote)</small>.</li>
   * <li>Strings do not need to be quoted at all if they do not begin with a
   * quote or single quote, and if they do not contain leading or trailing
   * spaces, and if they do not contain any of these characters:
   * <code>{ } [ ] / \ : , #</code> and if they do not look like numbers and
   * if they are not the reserved words <code>true</code>, <code>false</code>,
   * or <code>null</code>.</li>
   * </ul>
   *
   * @author JSON.org
   * @version 2016-08-15
   */
  public class JSONObject {
      /**
       * JSONObject.NULL is equivalent to the value that JavaScript calls null,
       * whilst Java's null is equivalent to the value that JavaScript calls
       * undefined.
       */
      private static final class Null {
  
          /**
           * There is only intended to be a single instance of the NULL object,
           * so the clone method returns itself.
           *
           * @return NULL.
           */
          @Override
          protected final Object clone() {
              return this;
          }
  
          /**
           * A Null object is equal to the null value and to itself.
           *
           * @param object
           *            An object to test for nullness.
           * @return true if the object parameter is the JSONObject.NULL object or
           *         null.
           */
          @Override
          @SuppressWarnings("lgtm[java/unchecked-cast-in-equals]")
          public boolean equals(Object object) {
              return object == null || object == this;
          }
          /**
           * A Null object is equal to the null value and to itself.
           *
           * @return always returns 0.
           */
          @Override
          public int hashCode() {
              return 0;
          }
  
          /**
           * Get the "null" string value.
           *
           * @return The string "null".
           */
          @Override
          public String toString() {
              return "null";
          }
      }
  
      /**
       *  Regular Expression Pattern that matches JSON Numbers. This is primarily used for
       *  output to guarantee that we are always writing valid JSON.
       */
      static final Pattern NUMBER_PATTERN = Pattern.compile("-?(?:0|[1-9]\\d*)(?:\\.\\d+)?(?:[eE][+-]?\\d+)?");
  
      /**
       * The map where the JSONObject's properties are kept.
       */
      private final Map<String, Object> map;
  
      /**
       * Retrieves the type of the underlying Map in this class.
       *
       * @return The class object representing the type of the underlying Map.
       */
      public Class<? extends Map> getMapType() {
          return map.getClass();
      }
  
      /**
       * It is sometimes more convenient and less ambiguous to have a
       * <code>NULL</code> object than to use Java's <code>null</code> value.
       * <code>JSONObject.NULL.equals(null)</code> returns <code>true</code>.
       * <code>JSONObject.NULL.toString()</code> returns <code>"null"</code>.
       */
      public static final Object NULL = new Null();
  
      /**
       * Construct an empty JSONObject.
       */
      public JSONObject() {
          // HashMap is used on purpose to ensure that elements are unordered by
          // the specification.
          // JSON tends to be a portable transfer format to allows the container
          // implementations to rearrange their items for a faster element
          // retrieval based on associative access.
          // Therefore, an implementation mustn't rely on the order of the item.
          this.map = new HashMap<String, Object>();
      }
  
      /**
       * Construct a JSONObject from a subset of another JSONObject. An array of
       * strings is used to identify the keys that should be copied. Missing keys
       * are ignored.
       *
       * @param jo
       *            A JSONObject.
       * @param names
       *            An array of strings.
       */
      public JSONObject(JSONObject jo, String ... names) {
          this(names.length);
          for (int i = 0; i < names.length; i += 1) {
              try {
                  this.putOnce(names[i], jo.opt(names[i]));
              } catch (Exception ignore) {
              }
          }
      }
  
      /**
       * Construct a JSONObject from a JSONTokener.
       *
       * @param x
       *            A JSONTokener object containing the source string.
       * @throws JSONException
       *             If there is a syntax error in the source string or a
       *             duplicated key.
       */
      public JSONObject(JSONTokener x) throws JSONException {
          this(x, x.getJsonParserConfiguration());
      }
  
      /**
       * Construct a JSONObject from a JSONTokener with custom json parse configurations.
       *
       * @param x
       *            A JSONTokener object containing the source string.
       * @param jsonParserConfiguration
       *            Variable to pass parser custom configuration for json parsing.
       * @throws JSONException
       *             If there is a syntax error in the source string or a
       *             duplicated key.
       */
      public JSONObject(JSONTokener x, JSONParserConfiguration jsonParserConfiguration) throws JSONException {
          this();
          char c;
          String key;
  
          boolean isInitial = x.getPrevious() == 0;
  
          if (x.nextClean() != '{') {
              throw x.syntaxError("A JSONObject text must begin with '{'");
          }
          for (;;) {
              c = x.nextClean();
              switch (c) {
              case 0:
                  throw x.syntaxError("A JSONObject text must end with '}'");
              case '}':
                  if (isInitial && jsonParserConfiguration.isStrictMode() && x.nextClean() != 0) {
                      throw x.syntaxError("Strict mode error: Unparsed characters found at end of input text");
                  }
                  return;
              default:
                  key = x.nextSimpleValue(c).toString();
              }
  
              // The key is followed by ':'.
  
              c = x.nextClean();
              if (c != ':') {
                  throw x.syntaxError("Expected a ':' after a key");
              }
  
              // Use syntaxError(..) to include error location
  
              if (key != null) {
                  // Check if key exists
                  boolean keyExists = this.opt(key) != null;
                  if (keyExists && !jsonParserConfiguration.isOverwriteDuplicateKey()) {
                      throw x.syntaxError("Duplicate key \"" + key + "\"");
                  }
  
                  Object value = x.nextValue();
                  // Only add value if non-null
                  if (value != null) {
                      this.put(key, value);
                  }
              }
  
              // Pairs are separated by ','.
  
              switch (x.nextClean()) {
              case ';':
                  // In strict mode semicolon is not a valid separator
                  if (jsonParserConfiguration.isStrictMode()) {
                      throw x.syntaxError("Strict mode error: Invalid character ';' found");
                  }
              case ',':
                  if (x.nextClean() == '}') {
                      // trailing commas are not allowed in strict mode
                      if (jsonParserConfiguration.isStrictMode()) {
                          throw x.syntaxError("Strict mode error: Expected another object element");
                      }
                      return;
                  }
                  if (x.end()) {
                      throw x.syntaxError("A JSONObject text must end with '}'");
                  }
                  x.back();
                  break;
              case '}':
                  if (isInitial && jsonParserConfiguration.isStrictMode() && x.nextClean() != 0) {
                      throw x.syntaxError("Strict mode error: Unparsed characters found at end of input text");
                  }
                  return;
              default:
                  throw x.syntaxError("Expected a ',' or '}'");
              }
          }
      }
  
      /**
       * Construct a JSONObject from a Map.
       *
       * @param m
       *            A map object that can be used to initialize the contents of
       *            the JSONObject.
       * @throws JSONException
       *            If a value in the map is non-finite number.
       * @throws NullPointerException
       *            If a key in the map is <code>null</code>
       */
      public JSONObject(Map<?, ?> m) {
        this(m, 0, new JSONParserConfiguration());
      }
  
      /**
       * Construct a JSONObject from a Map with custom json parse configurations.
       *
       * @param m
       *            A map object that can be used to initialize the contents of
       *            the JSONObject.
       * @param jsonParserConfiguration
       *            Variable to pass parser custom configuration for json parsing.
       */
      public JSONObject(Map<?, ?> m, JSONParserConfiguration jsonParserConfiguration) {
          this(m, 0, jsonParserConfiguration);
      }
  
      /**
       * Construct a JSONObject from a map with recursion depth.
       */
      private JSONObject(Map<?, ?> m, int recursionDepth, JSONParserConfiguration jsonParserConfiguration) {
          if (recursionDepth > jsonParserConfiguration.getMaxNestingDepth()) {
            throw new JSONException("JSONObject has reached recursion depth limit of " + jsonParserConfiguration.getMaxNestingDepth());
          }
          if (m == null) {
              this.map = new HashMap<String, Object>();
          } else {
              this.map = new HashMap<String, Object>(m.size());
          	for (final Entry<?, ?> e : m.entrySet()) {
          	    if(e.getKey() == null) {
          	        throw new NullPointerException("Null key.");
          	    }
                  final Object value = e.getValue();
                  if (value != null || jsonParserConfiguration.isUseNativeNulls()) {
                      testValidity(value);
                      this.map.put(String.valueOf(e.getKey()), wrap(value, recursionDepth + 1, jsonParserConfiguration));
                  }
              }
          }
      }
  
      /**
       * Construct a JSONObject from an Object using bean getters. It reflects on
       * all of the public methods of the object. For each of the methods with no
       * parameters and a name starting with <code>"get"</code> or
       * <code>"is"</code> followed by an uppercase letter, the method is invoked,
       * and a key and the value returned from the getter method are put into the
       * new JSONObject.
       * <p>
       * The key is formed by removing the <code>"get"</code> or <code>"is"</code>
       * prefix. If the second remaining character is not upper case, then the
       * first character is converted to lower case.
       * <p>
       * Methods that are <code>static</code>, return <code>void</code>,
       * have parameters, or are "bridge" methods, are ignored.
       * <p>
       * For example, if an object has a method named <code>"getName"</code>, and
       * if the result of calling <code>object.getName()</code> is
       * <code>"Larry Fine"</code>, then the JSONObject will contain
       * <code>"name": "Larry Fine"</code>.
       * <p>
       * The {@link JSONPropertyName} annotation can be used on a bean getter to
       * override key name used in the JSONObject. For example, using the object
       * above with the <code>getName</code> method, if we annotated it with:
       * <pre>
       * &#64;JSONPropertyName("FullName")
       * public String getName() { return this.name; }
       * </pre>
       * The resulting JSON object would contain <code>"FullName": "Larry Fine"</code>
       * <p>
       * Similarly, the {@link JSONPropertyName} annotation can be used on non-
       * <code>get</code> and <code>is</code> methods. We can also override key
       * name used in the JSONObject as seen below even though the field would normally
       * be ignored:
       * <pre>
       * &#64;JSONPropertyName("FullName")
       * public String fullName() { return this.name; }
       * </pre>
       * The resulting JSON object would contain <code>"FullName": "Larry Fine"</code>
       * <p>
       * The {@link JSONPropertyIgnore} annotation can be used to force the bean property
       * to not be serialized into JSON. If both {@link JSONPropertyIgnore} and
       * {@link JSONPropertyName} are defined on the same method, a depth comparison is
       * performed and the one closest to the concrete class being serialized is used.
       * If both annotations are at the same level, then the {@link JSONPropertyIgnore}
       * annotation takes precedent and the field is not serialized.
       * For example, the following declaration would prevent the <code>getName</code>
       * method from being serialized:
       * <pre>
       * &#64;JSONPropertyName("FullName")
       * &#64;JSONPropertyIgnore
       * public String getName() { return this.name; }
       * </pre>
       *
       * @param bean
       *            An object that has getter methods that should be used to make
       *            a JSONObject.
       * @throws JSONException
       *            If a getter returned a non-finite number.
       */
      public JSONObject(Object bean) {
          this();
          this.populateMap(bean, new JSONParserConfiguration());
      }
  
      public JSONObject(Object bean, JSONParserConfiguration jsonParserConfiguration) {
          this();
          this.populateMap(bean, jsonParserConfiguration);
      }
  
      private JSONObject(Object bean, Set<Object> objectsRecord) {
          this();
          this.populateMap(bean, objectsRecord, new JSONParserConfiguration());
      }
  
      /**
       * Construct a JSONObject from an Object, using reflection to find the
       * public members. The resulting JSONObject's keys will be the strings from
       * the names array, and the values will be the field values associated with
       * those keys in the object. If a key is not found or not visible, then it
       * will not be copied into the new JSONObject.
       *
       * @param object
       *            An object that has fields that should be used to make a
       *            JSONObject.
       * @param names
       *            An array of strings, the names of the fields to be obtained
       *            from the object.
       */
      public JSONObject(Object object, String ... names) {
          this(names.length);
          Class<?> c = object.getClass();
          for (int i = 0; i < names.length; i += 1) {
              String name = names[i];
              try {
                  this.putOpt(name, c.getField(name).get(object));
              } catch (Exception ignore) {
              }
          }
      }
  
      /**
       * Construct a JSONObject from a source JSON text string. This is the most
       * commonly used JSONObject constructor.
       *
       * @param source
       *            A string beginning with <code>{</code>&nbsp;<small>(left
       *            brace)</small> and ending with <code>}</code>
       *            &nbsp;<small>(right brace)</small>.
       * @exception JSONException
       *                If there is a syntax error in the source string or a
       *                duplicated key.
       */
      public JSONObject(String source) throws JSONException {
          this(source, new JSONParserConfiguration());
      }
  
      /**
       * Construct a JSONObject from a source JSON text string with custom json parse configurations.
       * This is the most commonly used JSONObject constructor.
       *
       * @param source
       *            A string beginning with <code>{</code>&nbsp;<small>(left
       *            brace)</small> and ending with <code>}</code>
       *            &nbsp;<small>(right brace)</small>.
       * @param jsonParserConfiguration
       *            Variable to pass parser custom configuration for json parsing.
       * @exception JSONException
       *                If there is a syntax error in the source string or a
       *                duplicated key.
       */
      public JSONObject(String source, JSONParserConfiguration jsonParserConfiguration) throws JSONException {
          this(new JSONTokener(source, jsonParserConfiguration), jsonParserConfiguration);
      }
  
      /**
       * Construct a JSONObject from a ResourceBundle.
       *
       * @param baseName
       *            The ResourceBundle base name.
       * @param locale
       *            The Locale to load the ResourceBundle for.
       * @throws JSONException
       *             If any JSONExceptions are detected.
       */
      public JSONObject(String baseName, Locale locale) throws JSONException {
          this();
          ResourceBundle bundle = ResourceBundle.getBundle(baseName, locale,
                  Thread.currentThread().getContextClassLoader());
  
  // Iterate through the keys in the bundle.
  
          Enumeration<String> keys = bundle.getKeys();
          while (keys.hasMoreElements()) {
              Object key = keys.nextElement();
              if (key != null) {
  
  // Go through the path, ensuring that there is a nested JSONObject for each
  // segment except the last. Add the value using the last segment's name into
  // the deepest nested JSONObject.
  
                  String[] path = ((String) key).split("\\.");
                  int last = path.length - 1;
                  JSONObject target = this;
                  for (int i = 0; i < last; i += 1) {
                      String segment = path[i];
                      JSONObject nextTarget = target.optJSONObject(segment);
                      if (nextTarget == null) {
                          nextTarget = new JSONObject();
                          target.put(segment, nextTarget);
                      }
                      target = nextTarget;
                  }
                  target.put(path[last], bundle.getString((String) key));
              }
          }
      }
  
      /**
       * Constructor to specify an initial capacity of the internal map. Useful for library
       * internal calls where we know, or at least can best guess, how big this JSONObject
       * will be.
       *
       * @param initialCapacity initial capacity of the internal map.
       */
      protected JSONObject(int initialCapacity){
          this.map = new HashMap<String, Object>(initialCapacity);
      }
  
      /**
       * Accumulate values under a key. It is similar to the put method except
       * that if there is already an object stored under the key then a JSONArray
       * is stored under the key to hold all of the accumulated values. If there
       * is already a JSONArray, then the new value is appended to it. In
       * contrast, the put method replaces the previous value.
       *
       * If only one value is accumulated that is not a JSONArray, then the result
       * will be the same as using put. But if multiple values are accumulated,
       * then the result will be like append.
       *
       * @param key
       *            A key string.
       * @param value
       *            An object to be accumulated under the key.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject accumulate(String key, Object value) throws JSONException {
          testValidity(value);
          Object object = this.opt(key);
          if (object == null) {
              this.put(key,
                      value instanceof JSONArray ? new JSONArray().put(value)
                              : value);
          } else if (object instanceof JSONArray) {
              ((JSONArray) object).put(value);
          } else {
              this.put(key, new JSONArray().put(object).put(value));
          }
          return this;
      }
  
      /**
       * Append values to the array under a key. If the key does not exist in the
       * JSONObject, then the key is put in the JSONObject with its value being a
       * JSONArray containing the value parameter. If the key was already
       * associated with a JSONArray, then the value parameter is appended to it.
       *
       * @param key
       *            A key string.
       * @param value
       *            An object to be accumulated under the key.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number or if the current value associated with
       *             the key is not a JSONArray.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject append(String key, Object value) throws JSONException {
          testValidity(value);
          Object object = this.opt(key);
          if (object == null) {
              this.put(key, new JSONArray().put(value));
          } else if (object instanceof JSONArray) {
              this.put(key, ((JSONArray) object).put(value));
          } else {
              throw wrongValueFormatException(key, "JSONArray", null, null);
          }
          return this;
      }
  
      /**
       * Produce a string from a double. The string "null" will be returned if the
       * number is not finite.
       *
       * @param d
       *            A double.
       * @return A String.
       */
      public static String doubleToString(double d) {
          if (Double.isInfinite(d) || Double.isNaN(d)) {
              return "null";
          }
  
  // Shave off trailing zeros and decimal point, if possible.
  
          String string = Double.toString(d);
          if (string.indexOf('.') > 0 && string.indexOf('e') < 0
                  && string.indexOf('E') < 0) {
              while (string.endsWith("0")) {
                  string = string.substring(0, string.length() - 1);
              }
              if (string.endsWith(".")) {
                  string = string.substring(0, string.length() - 1);
              }
          }
          return string;
      }
  
      /**
       * Get the value object associated with a key.
       *
       * @param key
       *            A key string.
       * @return The object associated with the key.
       * @throws JSONException
       *             if the key is not found.
       */
      public Object get(String key) throws JSONException {
          if (key == null) {
              throw new JSONException("Null key.");
          }
          Object object = this.opt(key);
          if (object == null) {
              throw new JSONException("JSONObject[" + quote(key) + "] not found.");
          }
          return object;
      }
  
      /**
       * Get the enum value associated with a key.
       *
       * @param <E>
       *            Enum Type
       * @param clazz
       *           The type of enum to retrieve.
       * @param key
       *           A key string.
       * @return The enum value associated with the key
       * @throws JSONException
       *             if the key is not found or if the value cannot be converted
       *             to an enum.
       */
      public <E extends Enum<E>> E getEnum(Class<E> clazz, String key) throws JSONException {
          E val = optEnum(clazz, key);
          if(val==null) {
              // JSONException should really take a throwable argument.
              // If it did, I would re-implement this with the Enum.valueOf
              // method and place any thrown exception in the JSONException
              throw wrongValueFormatException(key, "enum of type " + quote(clazz.getSimpleName()), opt(key), null);
          }
          return val;
      }
  
      /**
       * Get the boolean value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The truth.
       * @throws JSONException
       *             if the value is not a Boolean or the String "true" or
       *             "false".
       */
      public boolean getBoolean(String key) throws JSONException {
          Object object = this.get(key);
          if (object.equals(Boolean.FALSE)
                  || (object instanceof String && ((String) object)
                          .equalsIgnoreCase("false"))) {
              return false;
          } else if (object.equals(Boolean.TRUE)
                  || (object instanceof String && ((String) object)
                          .equalsIgnoreCase("true"))) {
              return true;
          }
          throw wrongValueFormatException(key, "Boolean", object, null);
      }
  
      /**
       * Get the BigInteger value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The numeric value.
       * @throws JSONException
       *             if the key is not found or if the value cannot
       *             be converted to BigInteger.
       */
      public BigInteger getBigInteger(String key) throws JSONException {
          Object object = this.get(key);
          BigInteger ret = objectToBigInteger(object, null);
          if (ret != null) {
              return ret;
          }
          throw wrongValueFormatException(key, "BigInteger", object, null);
      }
  
      /**
       * Get the BigDecimal value associated with a key. If the value is float or
       * double, the {@link BigDecimal#BigDecimal(double)} constructor will
       * be used. See notes on the constructor for conversion issues that may
       * arise.
       *
       * @param key
       *            A key string.
       * @return The numeric value.
       * @throws JSONException
       *             if the key is not found or if the value
       *             cannot be converted to BigDecimal.
       */
      public BigDecimal getBigDecimal(String key) throws JSONException {
          Object object = this.get(key);
          BigDecimal ret = objectToBigDecimal(object, null);
          if (ret != null) {
              return ret;
          }
          throw wrongValueFormatException(key, "BigDecimal", object, null);
      }
  
      /**
       * Get the double value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The numeric value.
       * @throws JSONException
       *             if the key is not found or if the value is not a Number
       *             object and cannot be converted to a number.
       */
      public double getDouble(String key) throws JSONException {
          final Object object = this.get(key);
          if(object instanceof Number) {
              return ((Number)object).doubleValue();
          }
          try {
              return Double.parseDouble(object.toString());
          } catch (Exception e) {
              throw wrongValueFormatException(key, "double", object, e);
          }
      }
  
      /**
       * Get the float value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The numeric value.
       * @throws JSONException
       *             if the key is not found or if the value is not a Number
       *             object and cannot be converted to a number.
       */
      public float getFloat(String key) throws JSONException {
          final Object object = this.get(key);
          if(object instanceof Number) {
              return ((Number)object).floatValue();
          }
          try {
              return Float.parseFloat(object.toString());
          } catch (Exception e) {
              throw wrongValueFormatException(key, "float", object, e);
          }
      }
  
      /**
       * Get the Number value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The numeric value.
       * @throws JSONException
       *             if the key is not found or if the value is not a Number
       *             object and cannot be converted to a number.
       */
      public Number getNumber(String key) throws JSONException {
          Object object = this.get(key);
          try {
              if (object instanceof Number) {
                  return (Number)object;
              }
              return stringToNumber(object.toString());
          } catch (Exception e) {
              throw wrongValueFormatException(key, "number", object, e);
          }
      }
  
      /**
       * Get the int value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The integer value.
       * @throws JSONException
       *             if the key is not found or if the value cannot be converted
       *             to an integer.
       */
      public int getInt(String key) throws JSONException {
          final Object object = this.get(key);
          if(object instanceof Number) {
              return ((Number)object).intValue();
          }
          try {
              return Integer.parseInt(object.toString());
          } catch (Exception e) {
              throw wrongValueFormatException(key, "int", object, e);
          }
      }
  
      /**
       * Get the JSONArray value associated with a key.
       *
       * @param key
       *            A key string.
       * @return A JSONArray which is the value.
       * @throws JSONException
       *             if the key is not found or if the value is not a JSONArray.
       */
      public JSONArray getJSONArray(String key) throws JSONException {
          Object object = this.get(key);
          if (object instanceof JSONArray) {
              return (JSONArray) object;
          }
          throw wrongValueFormatException(key, "JSONArray", object, null);
      }
  
      /**
       * Get the JSONObject value associated with a key.
       *
       * @param key
       *            A key string.
       * @return A JSONObject which is the value.
       * @throws JSONException
       *             if the key is not found or if the value is not a JSONObject.
       */
      public JSONObject getJSONObject(String key) throws JSONException {
          Object object = this.get(key);
          if (object instanceof JSONObject) {
              return (JSONObject) object;
          }
          throw wrongValueFormatException(key, "JSONObject", object, null);
      }
  
      /**
       * Get the long value associated with a key.
       *
       * @param key
       *            A key string.
       * @return The long value.
       * @throws JSONException
       *             if the key is not found or if the value cannot be converted
       *             to a long.
       */
      public long getLong(String key) throws JSONException {
          final Object object = this.get(key);
          if(object instanceof Number) {
              return ((Number)object).longValue();
          }
          try {
              return Long.parseLong(object.toString());
          } catch (Exception e) {
              throw wrongValueFormatException(key, "long", object, e);
          }
      }
  
      /**
       * Get an array of field names from a JSONObject.
       *
       * @param jo
       *            JSON object
       * @return An array of field names, or null if there are no names.
       */
      public static String[] getNames(JSONObject jo) {
          if (jo.isEmpty()) {
              return null;
          }
          return jo.keySet().toArray(new String[jo.length()]);
      }
  
      /**
       * Get an array of public field names from an Object.
       *
       * @param object
       *            object to read
       * @return An array of field names, or null if there are no names.
       */
      public static String[] getNames(Object object) {
          if (object == null) {
              return null;
          }
          Class<?> klass = object.getClass();
          Field[] fields = klass.getFields();
          int length = fields.length;
          if (length == 0) {
              return null;
          }
          String[] names = new String[length];
          for (int i = 0; i < length; i += 1) {
              names[i] = fields[i].getName();
          }
          return names;
      }
  
      /**
       * Get the string associated with a key.
       *
       * @param key
       *            A key string.
       * @return A string which is the value.
       * @throws JSONException
       *             if there is no string value for the key.
       */
      public String getString(String key) throws JSONException {
          Object object = this.get(key);
          if (object instanceof String) {
              return (String) object;
          }
          throw wrongValueFormatException(key, "string", object, null);
      }
  
      /**
       * Determine if the JSONObject contains a specific key.
       *
       * @param key
       *            A key string.
       * @return true if the key exists in the JSONObject.
       */
      public boolean has(String key) {
          return this.map.containsKey(key);
      }
  
      /**
       * Increment a property of a JSONObject. If there is no such property,
       * create one with a value of 1 (Integer). If there is such a property, and if it is
       * an Integer, Long, Double, Float, BigInteger, or BigDecimal then add one to it.
       * No overflow bounds checking is performed, so callers should initialize the key
       * prior to this call with an appropriate type that can handle the maximum expected
       * value.
       *
       * @param key
       *            A key string.
       * @return this.
       * @throws JSONException
       *             If there is already a property with this name that is not an
       *             Integer, Long, Double, or Float.
       */
      public JSONObject increment(String key) throws JSONException {
          Object value = this.opt(key);
          if (value == null) {
              this.put(key, 1);
          } else if (value instanceof Integer) {
              this.put(key, ((Integer) value).intValue() + 1);
          } else if (value instanceof Long) {
              this.put(key, ((Long) value).longValue() + 1L);
          } else if (value instanceof BigInteger) {
              this.put(key, ((BigInteger)value).add(BigInteger.ONE));
          } else if (value instanceof Float) {
              this.put(key, ((Float) value).floatValue() + 1.0f);
          } else if (value instanceof Double) {
              this.put(key, ((Double) value).doubleValue() + 1.0d);
          } else if (value instanceof BigDecimal) {
              this.put(key, ((BigDecimal)value).add(BigDecimal.ONE));
          } else {
              throw new JSONException("Unable to increment [" + quote(key) + "].");
          }
          return this;
      }
  
      /**
       * Determine if the value associated with the key is <code>null</code> or if there is no
       * value.
       *
       * @param key
       *            A key string.
       * @return true if there is no value associated with the key or if the value
       *        is the JSONObject.NULL object.
       */
      public boolean isNull(String key) {
          return JSONObject.NULL.equals(this.opt(key));
      }
  
      /**
       * Get an enumeration of the keys of the JSONObject. Modifying this key Set will also
       * modify the JSONObject. Use with caution.
       *
       * @see Set#iterator()
       *
       * @return An iterator of the keys.
       */
      public Iterator<String> keys() {
          return this.keySet().iterator();
      }
  
      /**
       * Get a set of keys of the JSONObject. Modifying this key Set will also modify the
       * JSONObject. Use with caution.
       *
       * @see Map#keySet()
       *
       * @return A keySet.
       */
      public Set<String> keySet() {
          return this.map.keySet();
      }
  
      /**
       * Get a set of entries of the JSONObject. These are raw values and may not
       * match what is returned by the JSONObject get* and opt* functions. Modifying
       * the returned EntrySet or the Entry objects contained therein will modify the
       * backing JSONObject. This does not return a clone or a read-only view.
       *
       * Use with caution.
       *
       * @see Map#entrySet()
       *
       * @return An Entry Set
       */
      protected Set<Entry<String, Object>> entrySet() {
          return this.map.entrySet();
      }
  
      /**
       * Get the number of keys stored in the JSONObject.
       *
       * @return The number of keys in the JSONObject.
       */
      public int length() {
          return this.map.size();
      }
  
      /**
       * Removes all of the elements from this JSONObject.
       * The JSONObject will be empty after this call returns.
       */
      public void clear() {
          this.map.clear();
      }
  
      /**
       * Check if JSONObject is empty.
       *
       * @return true if JSONObject is empty, otherwise false.
       */
      public boolean isEmpty() {
          return this.map.isEmpty();
      }
  
      /**
       * Produce a JSONArray containing the names of the elements of this
       * JSONObject.
       *
       * @return A JSONArray containing the key strings, or null if the JSONObject
       *        is empty.
       */
      public JSONArray names() {
      	if(this.map.isEmpty()) {
      		return null;
      	}
          return new JSONArray(this.map.keySet());
      }
  
      /**
       * Produce a string from a Number.
       *
       * @param number
       *            A Number
       * @return A String.
       * @throws JSONException
       *             If n is a non-finite number.
       */
      public static String numberToString(Number number) throws JSONException {
          if (number == null) {
              throw new JSONException("Null pointer");
          }
          testValidity(number);
  
          // Shave off trailing zeros and decimal point, if possible.
  
          String string = number.toString();
          if (string.indexOf('.') > 0 && string.indexOf('e') < 0
                  && string.indexOf('E') < 0) {
              while (string.endsWith("0")) {
                  string = string.substring(0, string.length() - 1);
              }
              if (string.endsWith(".")) {
                  string = string.substring(0, string.length() - 1);
              }
          }
          return string;
      }
  
      /**
       * Get an optional value associated with a key.
       *
       * @param key
       *            A key string.
       * @return An object which is the value, or null if there is no value.
       */
      public Object opt(String key) {
          return key == null ? null : this.map.get(key);
      }
  
      /**
       * Get the enum value associated with a key.
       *
       * @param <E>
       *            Enum Type
       * @param clazz
       *            The type of enum to retrieve.
       * @param key
       *            A key string.
       * @return The enum value associated with the key or null if not found
       */
      public <E extends Enum<E>> E optEnum(Class<E> clazz, String key) {
          return this.optEnum(clazz, key, null);
      }
  
      /**
       * Get the enum value associated with a key.
       *
       * @param <E>
       *            Enum Type
       * @param clazz
       *            The type of enum to retrieve.
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default in case the value is not found
       * @return The enum value associated with the key or defaultValue
       *            if the value is not found or cannot be assigned to <code>clazz</code>
       */
      public <E extends Enum<E>> E optEnum(Class<E> clazz, String key, E defaultValue) {
          try {
              Object val = this.opt(key);
              if (NULL.equals(val)) {
                  return defaultValue;
              }
              if (clazz.isAssignableFrom(val.getClass())) {
                  // we just checked it!
                  @SuppressWarnings("unchecked")
                  E myE = (E) val;
                  return myE;
              }
              return Enum.valueOf(clazz, val.toString());
          } catch (IllegalArgumentException e) {
              return defaultValue;
          } catch (NullPointerException e) {
              return defaultValue;
          }
      }
  
      /**
       * Get an optional boolean associated with a key. It returns false if there
       * is no such key, or if the value is not Boolean.TRUE or the String "true".
       *
       * @param key
       *            A key string.
       * @return The truth.
       */
      public boolean optBoolean(String key) {
          return this.optBoolean(key, false);
      }
  
      /**
       * Get an optional boolean associated with a key. It returns the
       * defaultValue if there is no such key, or if it is not a Boolean or the
       * String "true" or "false" (case insensitive).
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return The truth.
       */
      public boolean optBoolean(String key, boolean defaultValue) {
          Object val = this.opt(key);
          if (NULL.equals(val)) {
              return defaultValue;
          }
          if (val instanceof Boolean){
              return ((Boolean) val).booleanValue();
          }
          try {
              // we'll use the get anyway because it does string conversion.
              return this.getBoolean(key);
          } catch (Exception e) {
              return defaultValue;
          }
      }
  
      /**
       * Get an optional boolean object associated with a key. It returns false if there
       * is no such key, or if the value is not Boolean.TRUE or the String "true".
       *
       * @param key
       *            A key string.
       * @return The truth.
       */
      public Boolean optBooleanObject(String key) {
          return this.optBooleanObject(key, false);
      }
  
      /**
       * Get an optional boolean object associated with a key. It returns the
       * defaultValue if there is no such key, or if it is not a Boolean or the
       * String "true" or "false" (case insensitive).
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return The truth.
       */
      public Boolean optBooleanObject(String key, Boolean defaultValue) {
          Object val = this.opt(key);
          if (NULL.equals(val)) {
              return defaultValue;
          }
          if (val instanceof Boolean){
              return ((Boolean) val).booleanValue();
          }
          try {
              // we'll use the get anyway because it does string conversion.
              return this.getBoolean(key);
          } catch (Exception e) {
              return defaultValue;
          }
      }
  
      /**
       * Get an optional BigDecimal associated with a key, or the defaultValue if
       * there is no such key or if its value is not a number. If the value is a
       * string, an attempt will be made to evaluate it as a number. If the value
       * is float or double, then the {@link BigDecimal#BigDecimal(double)}
       * constructor will be used. See notes on the constructor for conversion
       * issues that may arise.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public BigDecimal optBigDecimal(String key, BigDecimal defaultValue) {
          Object val = this.opt(key);
          return objectToBigDecimal(val, defaultValue);
      }
  
      /**
       * @param val value to convert
       * @param defaultValue default value to return is the conversion doesn't work or is null.
       * @return BigDecimal conversion of the original value, or the defaultValue if unable
       *          to convert.
       */
      static BigDecimal objectToBigDecimal(Object val, BigDecimal defaultValue) {
          return objectToBigDecimal(val, defaultValue, true);
      }
  
      /**
       * @param val value to convert
       * @param defaultValue default value to return is the conversion doesn't work or is null.
       * @param exact When <code>true</code>, then {@link Double} and {@link Float} values will be converted exactly.
       *      When <code>false</code>, they will be converted to {@link String} values before converting to {@link BigDecimal}.
       * @return BigDecimal conversion of the original value, or the defaultValue if unable
       *          to convert.
       */
      static BigDecimal objectToBigDecimal(Object val, BigDecimal defaultValue, boolean exact) {
          if (NULL.equals(val)) {
              return defaultValue;
          }
          if (val instanceof BigDecimal){
              return (BigDecimal) val;
          }
          if (val instanceof BigInteger){
              return new BigDecimal((BigInteger) val);
          }
          if (val instanceof Double || val instanceof Float){
              if (!numberIsFinite((Number)val)) {
                  return defaultValue;
              }
              if (exact) {
                  return new BigDecimal(((Number)val).doubleValue());
              }
              // use the string constructor so that we maintain "nice" values for doubles and floats
              // the double constructor will translate doubles to "exact" values instead of the likely
              // intended representation
              return new BigDecimal(val.toString());
          }
          if (val instanceof Long || val instanceof Integer
                  || val instanceof Short || val instanceof Byte){
              return new BigDecimal(((Number) val).longValue());
          }
          // don't check if it's a string in case of unchecked Number subclasses
          try {
              return new BigDecimal(val.toString());
          } catch (Exception e) {
              return defaultValue;
          }
      }
  
      /**
       * Get an optional BigInteger associated with a key, or the defaultValue if
       * there is no such key or if its value is not a number. If the value is a
       * string, an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public BigInteger optBigInteger(String key, BigInteger defaultValue) {
          Object val = this.opt(key);
          return objectToBigInteger(val, defaultValue);
      }
  
      /**
       * @param val value to convert
       * @param defaultValue default value to return is the conversion doesn't work or is null.
       * @return BigInteger conversion of the original value, or the defaultValue if unable
       *          to convert.
       */
      static BigInteger objectToBigInteger(Object val, BigInteger defaultValue) {
          if (NULL.equals(val)) {
              return defaultValue;
          }
          if (val instanceof BigInteger){
              return (BigInteger) val;
          }
          if (val instanceof BigDecimal){
              return ((BigDecimal) val).toBigInteger();
          }
          if (val instanceof Double || val instanceof Float){
              if (!numberIsFinite((Number)val)) {
                  return defaultValue;
              }
              return new BigDecimal(((Number) val).doubleValue()).toBigInteger();
          }
          if (val instanceof Long || val instanceof Integer
                  || val instanceof Short || val instanceof Byte){
              return BigInteger.valueOf(((Number) val).longValue());
          }
          // don't check if it's a string in case of unchecked Number subclasses
          try {
              // the other opt functions handle implicit conversions, i.e.
              // jo.put("double",1.1d);
              // jo.optInt("double"); -- will return 1, not an error
              // this conversion to BigDecimal then to BigInteger is to maintain
              // that type cast support that may truncate the decimal.
              final String valStr = val.toString();
              if(isDecimalNotation(valStr)) {
                  return new BigDecimal(valStr).toBigInteger();
              }
              return new BigInteger(valStr);
          } catch (Exception e) {
              return defaultValue;
          }
      }
  
      /**
       * Get an optional double associated with a key, or NaN if there is no such
       * key or if its value is not a number. If the value is a string, an attempt
       * will be made to evaluate it as a number.
       *
       * @param key
       *            A string which is the key.
       * @return An object which is the value.
       */
      public double optDouble(String key) {
          return this.optDouble(key, Double.NaN);
      }
  
      /**
       * Get an optional double associated with a key, or the defaultValue if
       * there is no such key or if its value is not a number. If the value is a
       * string, an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public double optDouble(String key, double defaultValue) {
          Number val = this.optNumber(key);
          if (val == null) {
              return defaultValue;
          }
          return val.doubleValue();
      }
  
      /**
       * Get an optional Double object associated with a key, or NaN if there is no such
       * key or if its value is not a number. If the value is a string, an attempt
       * will be made to evaluate it as a number.
       *
       * @param key
       *            A string which is the key.
       * @return An object which is the value.
       */
      public Double optDoubleObject(String key) {
          return this.optDoubleObject(key, Double.NaN);
      }
  
      /**
       * Get an optional Double object associated with a key, or the defaultValue if
       * there is no such key or if its value is not a number. If the value is a
       * string, an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public Double optDoubleObject(String key, Double defaultValue) {
          Number val = this.optNumber(key);
          if (val == null) {
              return defaultValue;
          }
          return val.doubleValue();
      }
  
      /**
       * Get the optional float value associated with an index. NaN is returned
       * if there is no value for the index, or if the value is not a number and
       * cannot be converted to a number.
       *
       * @param key
       *            A key string.
       * @return The value.
       */
      public float optFloat(String key) {
          return this.optFloat(key, Float.NaN);
      }
  
      /**
       * Get the optional float value associated with an index. The defaultValue
       * is returned if there is no value for the index, or if the value is not a
       * number and cannot be converted to a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default value.
       * @return The value.
       */
      public float optFloat(String key, float defaultValue) {
          Number val = this.optNumber(key);
          if (val == null) {
              return defaultValue;
          }
          final float floatValue = val.floatValue();
          // if (Float.isNaN(floatValue) || Float.isInfinite(floatValue)) {
          // return defaultValue;
          // }
          return floatValue;
      }
  
      /**
       * Get the optional Float object associated with an index. NaN is returned
       * if there is no value for the index, or if the value is not a number and
       * cannot be converted to a number.
       *
       * @param key
       *            A key string.
       * @return The object.
       */
      public Float optFloatObject(String key) {
          return this.optFloatObject(key, Float.NaN);
      }
  
      /**
       * Get the optional Float object associated with an index. The defaultValue
       * is returned if there is no value for the index, or if the value is not a
       * number and cannot be converted to a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default object.
       * @return The object.
       */
      public Float optFloatObject(String key, Float defaultValue) {
          Number val = this.optNumber(key);
          if (val == null) {
              return defaultValue;
          }
          final Float floatValue = val.floatValue();
          // if (Float.isNaN(floatValue) || Float.isInfinite(floatValue)) {
          // return defaultValue;
          // }
          return floatValue;
      }
  
      /**
       * Get an optional int value associated with a key, or zero if there is no
       * such key or if the value is not a number. If the value is a string, an
       * attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @return An object which is the value.
       */
      public int optInt(String key) {
          return this.optInt(key, 0);
      }
  
      /**
       * Get an optional int value associated with a key, or the default if there
       * is no such key or if the value is not a number. If the value is a string,
       * an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public int optInt(String key, int defaultValue) {
          final Number val = this.optNumber(key, null);
          if (val == null) {
              return defaultValue;
          }
          return val.intValue();
      }
  
      /**
       * Get an optional Integer object associated with a key, or zero if there is no
       * such key or if the value is not a number. If the value is a string, an
       * attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @return An object which is the value.
       */
      public Integer optIntegerObject(String key) {
          return this.optIntegerObject(key, 0);
      }
  
      /**
       * Get an optional Integer object associated with a key, or the default if there
       * is no such key or if the value is not a number. If the value is a string,
       * an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public Integer optIntegerObject(String key, Integer defaultValue) {
          final Number val = this.optNumber(key, null);
          if (val == null) {
              return defaultValue;
          }
          return val.intValue();
      }
  
      /**
       * Get an optional JSONArray associated with a key. It returns null if there
       * is no such key, or if its value is not a JSONArray.
       *
       * @param key
       *            A key string.
       * @return A JSONArray which is the value.
       */
      public JSONArray optJSONArray(String key) {
          return this.optJSONArray(key, null);
      }
  
      /**
       * Get an optional JSONArray associated with a key, or the default if there
       * is no such key, or if its value is not a JSONArray.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return A JSONArray which is the value.
       */
      public JSONArray optJSONArray(String key, JSONArray defaultValue) {
          Object object = this.opt(key);
          return object instanceof JSONArray ? (JSONArray) object : defaultValue;
      }
  
      /**
       * Get an optional JSONObject associated with a key. It returns null if
       * there is no such key, or if its value is not a JSONObject.
       *
       * @param key
       *            A key string.
       * @return A JSONObject which is the value.
       */
      public JSONObject optJSONObject(String key) { return this.optJSONObject(key, null); }
  
      /**
       * Get an optional JSONObject associated with a key, or the default if there
       * is no such key or if the value is not a JSONObject.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An JSONObject which is the value.
       */
      public JSONObject optJSONObject(String key, JSONObject defaultValue) {
          Object object = this.opt(key);
          return object instanceof JSONObject ? (JSONObject) object : defaultValue;
      }
  
      /**
       * Get an optional long value associated with a key, or zero if there is no
       * such key or if the value is not a number. If the value is a string, an
       * attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @return An object which is the value.
       */
      public long optLong(String key) {
          return this.optLong(key, 0);
      }
  
      /**
       * Get an optional long value associated with a key, or the default if there
       * is no such key or if the value is not a number. If the value is a string,
       * an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public long optLong(String key, long defaultValue) {
          final Number val = this.optNumber(key, null);
          if (val == null) {
              return defaultValue;
          }
  
          return val.longValue();
      }
  
      /**
       * Get an optional Long object associated with a key, or zero if there is no
       * such key or if the value is not a number. If the value is a string, an
       * attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @return An object which is the value.
       */
      public Long optLongObject(String key) {
          return this.optLongObject(key, 0L);
      }
  
      /**
       * Get an optional Long object associated with a key, or the default if there
       * is no such key or if the value is not a number. If the value is a string,
       * an attempt will be made to evaluate it as a number.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public Long optLongObject(String key, Long defaultValue) {
          final Number val = this.optNumber(key, null);
          if (val == null) {
              return defaultValue;
          }
  
          return val.longValue();
      }
  
      /**
       * Get an optional {@link Number} value associated with a key, or <code>null</code>
       * if there is no such key or if the value is not a number. If the value is a string,
       * an attempt will be made to evaluate it as a number ({@link BigDecimal}). This method
       * would be used in cases where type coercion of the number value is unwanted.
       *
       * @param key
       *            A key string.
       * @return An object which is the value.
       */
      public Number optNumber(String key) {
          return this.optNumber(key, null);
      }
  
      /**
       * Get an optional {@link Number} value associated with a key, or the default if there
       * is no such key or if the value is not a number. If the value is a string,
       * an attempt will be made to evaluate it as a number. This method
       * would be used in cases where type coercion of the number value is unwanted.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return An object which is the value.
       */
      public Number optNumber(String key, Number defaultValue) {
          Object val = this.opt(key);
          if (NULL.equals(val)) {
              return defaultValue;
          }
          if (val instanceof Number){
              return (Number) val;
          }
  
          try {
              return stringToNumber(val.toString());
          } catch (Exception e) {
              return defaultValue;
          }
      }
  
      /**
       * Get an optional string associated with a key. It returns an empty string
       * if there is no such key. If the value is not a string and is not null,
       * then it is converted to a string.
       *
       * @param key
       *            A key string.
       * @return A string which is the value.
       */
      public String optString(String key) {
          return this.optString(key, "");
      }
  
      /**
       * Get an optional string associated with a key. It returns the defaultValue
       * if there is no such key.
       *
       * @param key
       *            A key string.
       * @param defaultValue
       *            The default.
       * @return A string which is the value.
       */
      public String optString(String key, String defaultValue) {
          Object object = this.opt(key);
          return NULL.equals(object) ? defaultValue : object.toString();
      }
  
      /**
       * Populates the internal map of the JSONObject with the bean properties. The
       * bean can not be recursive.
       *
       * @see JSONObject#JSONObject(Object)
       *
       * @param bean
       *            the bean
       * @throws JSONException
       *            If a getter returned a non-finite number.
       */
      private void populateMap(Object bean, JSONParserConfiguration jsonParserConfiguration) {
          populateMap(bean, Collections.newSetFromMap(new IdentityHashMap<Object, Boolean>()), jsonParserConfiguration);
      }
  
      private void populateMap(Object bean, Set<Object> objectsRecord, JSONParserConfiguration jsonParserConfiguration) {
          Class<?> klass = bean.getClass();
  
          // If klass is a System class then set includeSuperClass to false.
  
          boolean includeSuperClass = klass.getClassLoader() != null;
  
          Method[] methods = includeSuperClass ? klass.getMethods() : klass.getDeclaredMethods();
          for (final Method method : methods) {
              final int modifiers = method.getModifiers();
              if (Modifier.isPublic(modifiers)
                      && !Modifier.isStatic(modifiers)
                      && method.getParameterTypes().length == 0
                      && !method.isBridge()
                      && method.getReturnType() != Void.TYPE
                      && isValidMethodName(method.getName())) {
                  final String key = getKeyNameFromMethod(method);
                  if (key != null && !key.isEmpty()) {
                      try {
                          final Object result = method.invoke(bean);
                          if (result != null || jsonParserConfiguration.isUseNativeNulls()) {
                              // check cyclic dependency and throw error if needed
                              // the wrap and populateMap combination method is
                              // itself DFS recursive
                              if (objectsRecord.contains(result)) {
                                  throw recursivelyDefinedObjectException(key);
                              }
  
                              objectsRecord.add(result);
  
                              testValidity(result);
                              this.map.put(key, wrap(result, objectsRecord));
  
                              objectsRecord.remove(result);
  
                              // we don't use the result anywhere outside of wrap
                              // if it's a resource we should be sure to close it
                              // after calling toString
                              if (result instanceof Closeable) {
                                  try {
                                      ((Closeable) result).close();
                                  } catch (IOException ignore) {
                                  }
                              }
                          }
                      } catch (IllegalAccessException ignore) {
                      } catch (IllegalArgumentException ignore) {
                      } catch (InvocationTargetException ignore) {
                      }
                  }
              }
          }
      }
  
      private static boolean isValidMethodName(String name) {
          return !"getClass".equals(name) && !"getDeclaringClass".equals(name);
      }
  
      private static String getKeyNameFromMethod(Method method) {
          final int ignoreDepth = getAnnotationDepth(method, JSONPropertyIgnore.class);
          if (ignoreDepth > 0) {
              final int forcedNameDepth = getAnnotationDepth(method, JSONPropertyName.class);
              if (forcedNameDepth < 0 || ignoreDepth <= forcedNameDepth) {
                  // the hierarchy asked to ignore, and the nearest name override
                  // was higher or non-existent
                  return null;
              }
          }
          JSONPropertyName annotation = getAnnotation(method, JSONPropertyName.class);
          if (annotation != null && annotation.value() != null && !annotation.value().isEmpty()) {
              return annotation.value();
          }
          String key;
          final String name = method.getName();
          if (name.startsWith("get") && name.length() > 3) {
              key = name.substring(3);
          } else if (name.startsWith("is") && name.length() > 2) {
              key = name.substring(2);
          } else {
              return null;
          }
          // if the first letter in the key is not uppercase, then skip.
          // This is to maintain backwards compatibility before PR406
          // (https://github.com/stleary/JSON-java/pull/406/)
          if (key.length() == 0 || Character.isLowerCase(key.charAt(0))) {
              return null;
          }
          if (key.length() == 1) {
              key = key.toLowerCase(Locale.ROOT);
          } else if (!Character.isUpperCase(key.charAt(1))) {
              key = key.substring(0, 1).toLowerCase(Locale.ROOT) + key.substring(1);
          }
          return key;
      }
  
      /**
       * Searches the class hierarchy to see if the method or it's super
       * implementations and interfaces has the annotation.
       *
       * @param <A>
       *            type of the annotation
       *
       * @param m
       *            method to check
       * @param annotationClass
       *            annotation to look for
       * @return the {@link Annotation} if the annotation exists on the current method
       *         or one of its super class definitions
       */
      private static <A extends Annotation> A getAnnotation(final Method m, final Class<A> annotationClass) {
          // if we have invalid data the result is null
          if (m == null || annotationClass == null) {
              return null;
          }
  
          if (m.isAnnotationPresent(annotationClass)) {
              return m.getAnnotation(annotationClass);
          }
  
          // if we've already reached the Object class, return null;
          Class<?> c = m.getDeclaringClass();
          if (c.getSuperclass() == null) {
              return null;
          }
  
          // check directly implemented interfaces for the method being checked
          for (Class<?> i : c.getInterfaces()) {
              try {
                  Method im = i.getMethod(m.getName(), m.getParameterTypes());
                  return getAnnotation(im, annotationClass);
              } catch (final SecurityException ex) {
                  continue;
              } catch (final NoSuchMethodException ex) {
                  continue;
              }
          }
  
          //If the superclass is Object, no annotations will be found any more
          if (c.getSuperclass().equals(Object.class))
              return null;
  
          try {
              return getAnnotation(
                      c.getSuperclass().getMethod(m.getName(), m.getParameterTypes()),
                      annotationClass);
          } catch (final SecurityException ex) {
              return null;
          } catch (final NoSuchMethodException ex) {
              return null;
          }
      }
  
      /**
       * Searches the class hierarchy to see if the method or it's super
       * implementations and interfaces has the annotation. Returns the depth of the
       * annotation in the hierarchy.
       *
       * @param m
       *            method to check
       * @param annotationClass
       *            annotation to look for
       * @return Depth of the annotation or -1 if the annotation is not on the method.
       */
      private static int getAnnotationDepth(final Method m, final Class<? extends Annotation> annotationClass) {
          // if we have invalid data the result is -1
          if (m == null || annotationClass == null) {
              return -1;
          }
  
          if (m.isAnnotationPresent(annotationClass)) {
              return 1;
          }
  
          // if we've already reached the Object class, return -1;
          Class<?> c = m.getDeclaringClass();
          if (c.getSuperclass() == null) {
              return -1;
          }
  
          // check directly implemented interfaces for the method being checked
          for (Class<?> i : c.getInterfaces()) {
              try {
                  Method im = i.getMethod(m.getName(), m.getParameterTypes());
                  int d = getAnnotationDepth(im, annotationClass);
                  if (d > 0) {
                      // since the annotation was on the interface, add 1
                      return d + 1;
                  }
              } catch (final SecurityException ex) {
                  continue;
              } catch (final NoSuchMethodException ex) {
                  continue;
              }
          }
  
          //If the superclass is Object, no annotations will be found any more
          if (c.getSuperclass().equals(Object.class))
              return -1;
  
          try {
              int d = getAnnotationDepth(
                      c.getSuperclass().getMethod(m.getName(), m.getParameterTypes()),
                      annotationClass);
              if (d > 0) {
                  // since the annotation was on the superclass, add 1
                  return d + 1;
              }
              return -1;
          } catch (final SecurityException ex) {
              return -1;
          } catch (final NoSuchMethodException ex) {
              return -1;
          }
      }
  
      /**
       * Put a key/boolean pair in the JSONObject.
       *
       * @param key
       *            A key string.
       * @param value
       *            A boolean which is the value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, boolean value) throws JSONException {
          return this.put(key, value ? Boolean.TRUE : Boolean.FALSE);
      }
  
      /**
       * Put a key/value pair in the JSONObject, where the value will be a
       * JSONArray which is produced from a Collection.
       *
       * @param key
       *            A key string.
       * @param value
       *            A Collection value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, Collection<?> value) throws JSONException {
          return this.put(key, new JSONArray(value));
      }
  
      /**
       * Put a key/double pair in the JSONObject.
       *
       * @param key
       *            A key string.
       * @param value
       *            A double which is the value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, double value) throws JSONException {
          return this.put(key, Double.valueOf(value));
      }
  
      /**
       * Put a key/float pair in the JSONObject.
       *
       * @param key
       *            A key string.
       * @param value
       *            A float which is the value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, float value) throws JSONException {
          return this.put(key, Float.valueOf(value));
      }
  
      /**
       * Put a key/int pair in the JSONObject.
       *
       * @param key
       *            A key string.
       * @param value
       *            An int which is the value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, int value) throws JSONException {
          return this.put(key, Integer.valueOf(value));
      }
  
      /**
       * Put a key/long pair in the JSONObject.
       *
       * @param key
       *            A key string.
       * @param value
       *            A long which is the value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, long value) throws JSONException {
          return this.put(key, Long.valueOf(value));
      }
  
      /**
       * Put a key/value pair in the JSONObject, where the value will be a
       * JSONObject which is produced from a Map.
       *
       * @param key
       *            A key string.
       * @param value
       *            A Map value.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, Map<?, ?> value) throws JSONException {
          return this.put(key, new JSONObject(value));
      }
  
      /**
       * Put a key/value pair in the JSONObject. If the value is <code>null</code>, then the
       * key will be removed from the JSONObject if it is present.
       *
       * @param key
       *            A key string.
       * @param value
       *            An object which is the value. It should be of one of these
       *            types: Boolean, Double, Integer, JSONArray, JSONObject, Long,
       *            String, or the JSONObject.NULL object.
       * @return this.
       * @throws JSONException
       *            If the value is non-finite number.
       * @throws NullPointerException
       *            If the key is <code>null</code>.
       */
      public JSONObject put(String key, Object value) throws JSONException {
          if (key == null) {
              throw new NullPointerException("Null key.");
          }
          if (value != null) {
              testValidity(value);
              this.map.put(key, value);
          } else {
              this.remove(key);
          }
          return this;
      }
  
      /**
       * Put a key/value pair in the JSONObject, but only if the key and the value
       * are both non-null, and only if there is not already a member with that
       * name.
       *
       * @param key
       *            key to insert into
       * @param value
       *            value to insert
       * @return this.
       * @throws JSONException
       *             if the key is a duplicate
       */
      public JSONObject putOnce(String key, Object value) throws JSONException {
          if (key != null && value != null) {
              if (this.opt(key) != null) {
                  throw new JSONException("Duplicate key \"" + key + "\"");
              }
              return this.put(key, value);
          }
          return this;
      }
  
      /**
       * Put a key/value pair in the JSONObject, but only if the key and the value
       * are both non-null.
       *
       * @param key
       *            A key string.
       * @param value
       *            An object which is the value. It should be of one of these
       *            types: Boolean, Double, Integer, JSONArray, JSONObject, Long,
       *            String, or the JSONObject.NULL object.
       * @return this.
       * @throws JSONException
       *             If the value is a non-finite number.
       */
      public JSONObject putOpt(String key, Object value) throws JSONException {
          if (key != null && value != null) {
              return this.put(key, value);
          }
          return this;
      }
  
      /**
       * Creates a JSONPointer using an initialization string and tries to
       * match it to an item within this JSONObject. For example, given a
       * JSONObject initialized with this document:
       * <pre>
       * {
       *     "a":{"b":"c"}
       * }
       * </pre>
       * and this JSONPointer string:
       * <pre>
       * "/a/b"
       * </pre>
       * Then this method will return the String "c".
       * A JSONPointerException may be thrown from code called by this method.
       *
       * @param jsonPointer string that can be used to create a JSONPointer
       * @return the item matched by the JSONPointer, otherwise null
       */
      public Object query(String jsonPointer) {
          return query(new JSONPointer(jsonPointer));
      }
      /**
       * Uses a user initialized JSONPointer  and tries to
       * match it to an item within this JSONObject. For example, given a
       * JSONObject initialized with this document:
       * <pre>
       * {
       *     "a":{"b":"c"}
       * }
       * </pre>
       * and this JSONPointer:
       * <pre>
       * "/a/b"
       * </pre>
       * Then this method will return the String "c".
       * A JSONPointerException may be thrown from code called by this method.
       *
       * @param jsonPointer string that can be used to create a JSONPointer
       * @return the item matched by the JSONPointer, otherwise null
       */
      public Object query(JSONPointer jsonPointer) {
          return jsonPointer.queryFrom(this);
      }
  
      /**
       * Queries and returns a value from this object using {@code jsonPointer}, or
       * returns null if the query fails due to a missing key.
       *
       * @param jsonPointer the string representation of the JSON pointer
       * @return the queried value or {@code null}
       * @throws IllegalArgumentException if {@code jsonPointer} has invalid syntax
       */
      public Object optQuery(String jsonPointer) {
      	return optQuery(new JSONPointer(jsonPointer));
      }
  
      /**
       * Queries and returns a value from this object using {@code jsonPointer}, or
       * returns null if the query fails due to a missing key.
       *
       * @param jsonPointer The JSON pointer
       * @return the queried value or {@code null}
       * @throws IllegalArgumentException if {@code jsonPointer} has invalid syntax
       */
      public Object optQuery(JSONPointer jsonPointer) {
          try {
              return jsonPointer.queryFrom(this);
          } catch (JSONPointerException e) {
              return null;
          }
      }
  
      /**
       * Produce a string in double quotes with backslash sequences in all the
       * right places. A backslash will be inserted within &lt;/, producing
       * &lt;\/, allowing JSON text to be delivered in HTML. In JSON text, a
       * string cannot contain a control character or an unescaped quote or
       * backslash.
       *
       * @param string
       *            A String
       * @return A String correctly formatted for insertion in a JSON text.
       */
      @SuppressWarnings("resource")
      public static String quote(String string) {
          if (string == null || string.isEmpty()) {
              return "\"\"";
          }
          Writer sw = new StringBuilderWriter(string.length() + 2);
          try {
              return quote(string, sw).toString();
          } catch (IOException ignored) {
              // will never happen - we are writing to a string writer
              return "";
          }
      }
  
      /**
       * Quotes a string and appends the result to a given Writer.
       *
       * @param string The input string to be quoted.
       * @param w      The Writer to which the quoted string will be appended.
       * @return The same Writer instance after appending the quoted string.
       * @throws IOException If an I/O error occurs while writing to the Writer.
       */
      public static Writer quote(String string, Writer w) throws IOException {
          if (string == null || string.isEmpty()) {
              w.write("\"\"");
              return w;
          }
  
          char b;
          char c = 0;
          String hhhh;
          int i;
          int len = string.length();
  
          w.write('"');
          for (i = 0; i < len; i += 1) {
              b = c;
              c = string.charAt(i);
              switch (c) {
              case '\\':
              case '"':
                  w.write('\\');
                  w.write(c);
                  break;
              case '/':
                  if (b == '<') {
                      w.write('\\');
                  }
                  w.write(c);
                  break;
              case '\b':
                  w.write("\\b");
                  break;
              case '\t':
                  w.write("\\t");
                  break;
              case '\n':
                  w.write("\\n");
                  break;
              case '\f':
                  w.write("\\f");
                  break;
              case '\r':
                  w.write("\\r");
                  break;
              default:
                  if (c < ' ' || (c >= '\u0080' && c < '\u00a0')
                          || (c >= '\u2000' && c < '\u2100')) {
                      w.write("\\u");
                      hhhh = Integer.toHexString(c);
                      w.write("0000", 0, 4 - hhhh.length());
                      w.write(hhhh);
                  } else {
                      w.write(c);
                  }
              }
          }
          w.write('"');
          return w;
      }
  
      /**
       * Remove a name and its value, if present.
       *
       * @param key
       *            The name to be removed.
       * @return The value that was associated with the name, or null if there was
       *         no value.
       */
      public Object remove(String key) {
          return this.map.remove(key);
      }
  
      /**
       * Determine if two JSONObjects are similar.
       * They must contain the same set of names which must be associated with
       * similar values.
       *
       * @param other The other JSONObject
       * @return true if they are equal
       */
      public boolean similar(Object other) {
          try {
              if (!(other instanceof JSONObject)) {
                  return false;
              }
              if (!this.keySet().equals(((JSONObject)other).keySet())) {
                  return false;
              }
              for (final Entry<String,?> entry : this.entrySet()) {
                  String name = entry.getKey();
                  Object valueThis = entry.getValue();
                  Object valueOther = ((JSONObject)other).get(name);
                  if(valueThis == valueOther) {
                  	continue;
                  }
                  if(valueThis == null) {
                  	return false;
                  }
                  if (valueThis instanceof JSONObject) {
                      if (!((JSONObject)valueThis).similar(valueOther)) {
                          return false;
                      }
                  } else if (valueThis instanceof JSONArray) {
                      if (!((JSONArray)valueThis).similar(valueOther)) {
                          return false;
                      }
                  } else if (valueThis instanceof Number && valueOther instanceof Number) {
                      if (!isNumberSimilar((Number)valueThis, (Number)valueOther)) {
                      	return false;
                      }
                  } else if (valueThis instanceof JSONString && valueOther instanceof JSONString) {
                      if (!((JSONString) valueThis).toJSONString().equals(((JSONString) valueOther).toJSONString())) {
                      	return false;
                      }
                  } else if (!valueThis.equals(valueOther)) {
                      return false;
                  }
              }
              return true;
          } catch (Throwable exception) {
              return false;
          }
      }
  
      /**
       * Compares two numbers to see if they are similar.
       *
       * If either of the numbers are Double or Float instances, then they are checked to have
       * a finite value. If either value is not finite (NaN or &#177;infinity), then this
       * function will always return false. If both numbers are finite, they are first checked
       * to be the same type and implement {@link Comparable}. If they do, then the actual
       * {@link Comparable#compareTo(Object)} is called. If they are not the same type, or don't
       * implement Comparable, then they are converted to {@link BigDecimal}s. Finally the
       * BigDecimal values are compared using {@link BigDecimal#compareTo(BigDecimal)}.
       *
       * @param l the Left value to compare. Can not be <code>null</code>.
       * @param r the right value to compare. Can not be <code>null</code>.
       * @return true if the numbers are similar, false otherwise.
       */
      static boolean isNumberSimilar(Number l, Number r) {
          if (!numberIsFinite(l) || !numberIsFinite(r)) {
              // non-finite numbers are never similar
              return false;
          }
  
          // if the classes are the same and implement Comparable
          // then use the built in compare first.
          if(l.getClass().equals(r.getClass()) && l instanceof Comparable) {
              @SuppressWarnings({ "rawtypes", "unchecked" })
              int compareTo = ((Comparable)l).compareTo(r);
              return compareTo==0;
          }
  
          // BigDecimal should be able to handle all of our number types that we support through
          // documentation. Convert to BigDecimal first, then use the Compare method to
          // decide equality.
          final BigDecimal lBigDecimal = objectToBigDecimal(l, null, false);
          final BigDecimal rBigDecimal = objectToBigDecimal(r, null, false);
          if (lBigDecimal == null || rBigDecimal == null) {
              return false;
          }
          return lBigDecimal.compareTo(rBigDecimal) == 0;
      }
  
      private static boolean numberIsFinite(Number n) {
          if (n instanceof Double && (((Double) n).isInfinite() || ((Double) n).isNaN())) {
              return false;
          } else if (n instanceof Float && (((Float) n).isInfinite() || ((Float) n).isNaN())) {
              return false;
          }
          return true;
      }
  
      /**
       * Tests if the value should be tried as a decimal. It makes no test if there are actual digits.
       *
       * @param val value to test
       * @return true if the string is "-0" or if it contains '.', 'e', or 'E', false otherwise.
       */
      protected static boolean isDecimalNotation(final String val) {
          return val.indexOf('.') > -1 || val.indexOf('e') > -1
                  || val.indexOf('E') > -1 || "-0".equals(val);
      }
  
      /**
       * Try to convert a string into a number, boolean, or null. If the string
       * can't be converted, return the string.
       *
       * @param string
       *            A String. can not be null.
       * @return A simple JSON value.
       * @throws NullPointerException
       *             Thrown if the string is null.
       */
      // Changes to this method must be copied to the corresponding method in
      // the XML class to keep full support for Android
      public static Object stringToValue(String string) {
          if ("".equals(string)) {
              return string;
          }
  
          // check JSON key words true/false/null
          if ("true".equalsIgnoreCase(string)) {
              return Boolean.TRUE;
          }
          if ("false".equalsIgnoreCase(string)) {
              return Boolean.FALSE;
          }
          if ("null".equalsIgnoreCase(string)) {
              return JSONObject.NULL;
          }
  
          /*
           * If it might be a number, try converting it. If a number cannot be
           * produced, then the value will just be a string.
           */
  
          char initial = string.charAt(0);
          if ((initial >= '0' && initial <= '9') || initial == '-') {
              try {
                  return stringToNumber(string);
              } catch (Exception ignore) {
              }
          }
          return string;
      }
  
      /**
       * Converts a string to a number using the narrowest possible type. Possible
       * returns for this function are BigDecimal, Double, BigInteger, Long, and Integer.
       * When a Double is returned, it should always be a valid Double and not NaN or +-infinity.
       *
       * @param val value to convert
       * @return Number representation of the value.
       * @throws NumberFormatException thrown if the value is not a valid number. A public
       *      caller should catch this and wrap it in a {@link JSONException} if applicable.
       */
      protected static Number stringToNumber(final String val) throws NumberFormatException {
          char initial = val.charAt(0);
          if ((initial >= '0' && initial <= '9') || initial == '-') {
              // decimal representation
              if (isDecimalNotation(val)) {
                  // Use a BigDecimal all the time so we keep the original
                  // representation. BigDecimal doesn't support -0.0, ensure we
                  // keep that by forcing a decimal.
                  try {
                      BigDecimal bd = new BigDecimal(val);
                      if(initial == '-' && BigDecimal.ZERO.compareTo(bd)==0) {
                          return Double.valueOf(-0.0);
                      }
                      return bd;
                  } catch (NumberFormatException retryAsDouble) {
                      // this is to support "Hex Floats" like this: 0x1.0P-1074
                      try {
                          Double d = Double.valueOf(val);
                          if(d.isNaN() || d.isInfinite()) {
                              throw new NumberFormatException("val ["+val+"] is not a valid number.");
                          }
                          return d;
                      } catch (NumberFormatException ignore) {
                          throw new NumberFormatException("val ["+val+"] is not a valid number.");
                      }
                  }
              }
              // block items like 00 01 etc. Java number parsers treat these as Octal.
              if(initial == '0' && val.length() > 1) {
                  char at1 = val.charAt(1);
                  if(at1 >= '0' && at1 <= '9') {
                      throw new NumberFormatException("val ["+val+"] is not a valid number.");
                  }
              } else if (initial == '-' && val.length() > 2) {
                  char at1 = val.charAt(1);
                  char at2 = val.charAt(2);
                  if(at1 == '0' && at2 >= '0' && at2 <= '9') {
                      throw new NumberFormatException("val ["+val+"] is not a valid number.");
                  }
              }
              // integer representation.
              // This will narrow any values to the smallest reasonable Object representation
              // (Integer, Long, or BigInteger)
  
              // BigInteger down conversion: We use a similar bitLength compare as
              // BigInteger#intValueExact uses. Increases GC, but objects hold
              // only what they need. i.e. Less runtime overhead if the value is
              // long lived.
              BigInteger bi = new BigInteger(val);
              if(bi.bitLength() <= 31){
                  return Integer.valueOf(bi.intValue());
              }
              if(bi.bitLength() <= 63){
                  return Long.valueOf(bi.longValue());
              }
              return bi;
          }
          throw new NumberFormatException("val ["+val+"] is not a valid number.");
      }
  
      /**
       * Throw an exception if the object is a NaN or infinite number.
       *
       * @param o
       *            The object to test.
       * @throws JSONException
       *             If o is a non-finite number.
       */
      public static void testValidity(Object o) throws JSONException {
          if (o instanceof Number && !numberIsFinite((Number) o)) {
              throw new JSONException("JSON does not allow non-finite numbers.");
          }
      }
  
      /**
       * Produce a JSONArray containing the values of the members of this
       * JSONObject.
       *
       * @param names
       *            A JSONArray containing a list of key strings. This determines
       *            the sequence of the values in the result.
       * @return A JSONArray of values.
       * @throws JSONException
       *             If any of the values are non-finite numbers.
       */
      public JSONArray toJSONArray(JSONArray names) throws JSONException {
          if (names == null || names.isEmpty()) {
              return null;
          }
          JSONArray ja = new JSONArray();
          for (int i = 0; i < names.length(); i += 1) {
              ja.put(this.opt(names.getString(i)));
          }
          return ja;
      }
  
      /**
       * Make a JSON text of this JSONObject. For compactness, no whitespace is
       * added. If this would not result in a syntactically correct JSON text,
       * then null will be returned instead.
       * <p><b>
       * Warning: This method assumes that the data structure is acyclical.
       * </b>
       *
       * @return a printable, displayable, portable, transmittable representation
       *         of the object, beginning with <code>{</code>&nbsp;<small>(left
       *         brace)</small> and ending with <code>}</code>&nbsp;<small>(right
       *         brace)</small>.
       */
      @Override
      public String toString() {
          try {
              return this.toString(0);
          } catch (Exception e) {
              return null;
          }
      }
  
      /**
       * Make a pretty-printed JSON text of this JSONObject.
       *
       * <p>If <pre>{@code indentFactor > 0}</pre> and the {@link JSONObject}
       * has only one key, then the object will be output on a single line:
       * <pre>{@code {"key": 1}}</pre>
       *
       * <p>If an object has 2 or more keys, then it will be output across
       * multiple lines: <pre>{@code {
       *  "key1": 1,
       *  "key2": "value 2",
       *  "key3": 3
       * }}</pre>
       * <p><b>
       * Warning: This method assumes that the data structure is acyclical.
       * </b>
       *
       * @param indentFactor
       *            The number of spaces to add to each level of indentation.
       * @return a printable, displayable, portable, transmittable representation
       *         of the object, beginning with <code>{</code>&nbsp;<small>(left
       *         brace)</small> and ending with <code>}</code>&nbsp;<small>(right
       *         brace)</small>.
       * @throws JSONException
       *             If the object contains an invalid number.
       */
      @SuppressWarnings("resource")
      public String toString(int indentFactor) throws JSONException {
          // 6 characters are the minimum to serialise a key value pair e.g.: "k":1,
          // and we don't want to oversize the initial capacity
          int initialSize = map.size() * 6;
          Writer w = new StringBuilderWriter(Math.max(initialSize, 16));
          return this.write(w, indentFactor, 0).toString();
      }
  
      /**
       * Make a JSON text of an Object value. If the object has an
       * value.toJSONString() method, then that method will be used to produce the
       * JSON text. The method is required to produce a strictly conforming text.
       * If the object does not contain a toJSONString method (which is the most
       * common case), then a text will be produced by other means. If the value
       * is an array or Collection, then a JSONArray will be made from it and its
       * toJSONString method will be called. If the value is a MAP, then a
       * JSONObject will be made from it and its toJSONString method will be
       * called. Otherwise, the value's toString method will be called, and the
       * result will be quoted.
       *
       * <p>
       * Warning: This method assumes that the data structure is acyclical.
       *
       * @param value
       *            The value to be serialized.
       * @return a printable, displayable, transmittable representation of the
       *         object, beginning with <code>{</code>&nbsp;<small>(left
       *         brace)</small> and ending with <code>}</code>&nbsp;<small>(right
       *         brace)</small>.
       * @throws JSONException
       *             If the value is or contains an invalid number.
       */
      public static String valueToString(Object value) throws JSONException {
      	// moves the implementation to JSONWriter as:
      	// 1. It makes more sense to be part of the writer class
      	// 2. For Android support this method is not available. By implementing it in the Writer
      	//    Android users can use the writer with the built in Android JSONObject implementation.
          return JSONWriter.valueToString(value);
      }
  
      /**
       * Wrap an object, if necessary. If the object is <code>null</code>, return the NULL
       * object. If it is an array or collection, wrap it in a JSONArray. If it is
       * a map, wrap it in a JSONObject. If it is a standard property (Double,
       * String, et al) then it is already wrapped. Otherwise, if it comes from
       * one of the java packages, turn it into a string. And if it doesn't, try
       * to wrap it in a JSONObject. If the wrapping fails, then null is returned.
       *
       * @param object
       *            The object to wrap
       * @return The wrapped value
       */
      public static Object wrap(Object object) {
          return wrap(object, null);
      }
  
      /**
       * Wrap an object, if necessary. If the object is <code>null</code>, return the NULL
       * object. If it is an array or collection, wrap it in a JSONArray. If it is
       * a map, wrap it in a JSONObject. If it is a standard property (Double,
       * String, et al) then it is already wrapped. Otherwise, if it comes from
       * one of the java packages, turn it into a string. And if it doesn't, try
       * to wrap it in a JSONObject. If the wrapping fails, then null is returned.
       *
       * @param object
       *            The object to wrap
       * @param recursionDepth
       *            Variable for tracking the count of nested object creations.
       * @param jsonParserConfiguration
       *            Variable to pass parser custom configuration for json parsing.
       * @return The wrapped value
       */
      static Object wrap(Object object, int recursionDepth, JSONParserConfiguration jsonParserConfiguration) {
        return wrap(object, null, recursionDepth, jsonParserConfiguration);
      }
  
      private static Object wrap(Object object, Set<Object> objectsRecord) {
        return wrap(object, objectsRecord, 0, new JSONParserConfiguration());
      }
  
      private static Object wrap(Object object, Set<Object> objectsRecord, int recursionDepth, JSONParserConfiguration jsonParserConfiguration) {
          try {
              if (NULL.equals(object)) {
                  return NULL;
              }
              if (object instanceof JSONObject || object instanceof JSONArray
                      || NULL.equals(object) || object instanceof JSONString
                      || object instanceof Byte || object instanceof Character
                      || object instanceof Short || object instanceof Integer
                      || object instanceof Long || object instanceof Boolean
                      || object instanceof Float || object instanceof Double
                      || object instanceof String || object instanceof BigInteger
                      || object instanceof BigDecimal || object instanceof Enum) {
                  return object;
              }
  
              if (object instanceof Collection) {
                  Collection<?> coll = (Collection<?>) object;
                  return new JSONArray(coll, recursionDepth, jsonParserConfiguration);
              }
              if (object.getClass().isArray()) {
                  return new JSONArray(object);
              }
              if (object instanceof Map) {
                  Map<?, ?> map = (Map<?, ?>) object;
                  return new JSONObject(map, recursionDepth, jsonParserConfiguration);
              }
              Package objectPackage = object.getClass().getPackage();
              String objectPackageName = objectPackage != null ? objectPackage
                      .getName() : "";
              if (objectPackageName.startsWith("java.")
                      || objectPackageName.startsWith("javax.")
                      || object.getClass().getClassLoader() == null) {
                  return object.toString();
              }
              if (objectsRecord != null) {
                  return new JSONObject(object, objectsRecord);
              }
              return new JSONObject(object);
          }
          catch (JSONException exception) {
              throw exception;
          } catch (Exception exception) {
              return null;
          }
      }
  
      /**
       * Write the contents of the JSONObject as JSON text to a writer. For
       * compactness, no whitespace is added.
       * <p><b>
       * Warning: This method assumes that the data structure is acyclical.
       * </b>
       * @param writer the writer object
       * @return The writer.
       * @throws JSONException if a called function has an error
       */
      public Writer write(Writer writer) throws JSONException {
          return this.write(writer, 0, 0);
      }
  
      @SuppressWarnings("resource")
      static final Writer writeValue(Writer writer, Object value,
              int indentFactor, int indent) throws JSONException, IOException {
          if (value == null || value.equals(null)) {
              writer.write("null");
          } else if (value instanceof JSONString) {
              // JSONString must be checked first, so it can overwrite behaviour of other types below
              Object o;
              try {
                  o = ((JSONString) value).toJSONString();
              } catch (Exception e) {
                  throw new JSONException(e);
              }
              writer.write(o != null ? o.toString() : quote(value.toString()));
          } else if (value instanceof String) {
              // assuming most values are Strings, so testing it early
              quote(value.toString(), writer);
              return writer;
          } else if (value instanceof Number) {
              // not all Numbers may match actual JSON Numbers. i.e. fractions or Imaginary
              final String numberAsString = numberToString((Number) value);
              if(NUMBER_PATTERN.matcher(numberAsString).matches()) {
                  writer.write(numberAsString);
              } else {
                  // The Number value is not a valid JSON number.
                  // Instead we will quote it as a string
                  quote(numberAsString, writer);
              }
          } else if (value instanceof Boolean) {
              writer.write(value.toString());
          } else if (value instanceof Enum<?>) {
              writer.write(quote(((Enum<?>)value).name()));
          } else if (value instanceof JSONObject) {
              ((JSONObject) value).write(writer, indentFactor, indent);
          } else if (value instanceof JSONArray) {
              ((JSONArray) value).write(writer, indentFactor, indent);
          } else if (value instanceof Map) {
              Map<?, ?> map = (Map<?, ?>) value;
              new JSONObject(map).write(writer, indentFactor, indent);
          } else if (value instanceof Collection) {
              Collection<?> coll = (Collection<?>) value;
              new JSONArray(coll).write(writer, indentFactor, indent);
          } else if (value.getClass().isArray()) {
              new JSONArray(value).write(writer, indentFactor, indent);
          } else {
              quote(value.toString(), writer);
          }
          return writer;
      }
  
      static final void indent(Writer writer, int indent) throws IOException {
          for (int i = 0; i < indent; i += 1) {
              writer.write(' ');
          }
      }
  
      /**
       * Write the contents of the JSONObject as JSON text to a writer.
       *
       * <p>If <pre>{@code indentFactor > 0}</pre> and the {@link JSONObject}
       * has only one key, then the object will be output on a single line:
       * <pre>{@code {"key": 1}}</pre>
       *
       * <p>If an object has 2 or more keys, then it will be output across
       * multiple lines: <pre>{@code {
       *  "key1": 1,
       *  "key2": "value 2",
       *  "key3": 3
       * }}</pre>
       * <p><b>
       * Warning: This method assumes that the data structure is acyclical.
       * </b>
       *
       * @param writer
       *            Writes the serialized JSON
       * @param indentFactor
       *            The number of spaces to add to each level of indentation.
       * @param indent
       *            The indentation of the top level.
       * @return The writer.
       * @throws JSONException if a called function has an error or a write error
       * occurs
       */
      @SuppressWarnings("resource")
      public Writer write(Writer writer, int indentFactor, int indent)
              throws JSONException {
          try {
              boolean needsComma = false;
              final int length = this.length();
              writer.write('{');
  
              if (length == 1) {
              	final Entry<String,?> entry = this.entrySet().iterator().next();
                  final String key = entry.getKey();
                  writer.write(quote(key));
                  writer.write(':');
                  if (indentFactor > 0) {
                      writer.write(' ');
                  }
                  try{
                      writeValue(writer, entry.getValue(), indentFactor, indent);
                  } catch (Exception e) {
                      throw new JSONException("Unable to write JSONObject value for key: " + key, e);
                  }
              } else if (length != 0) {
                  final int newIndent = indent + indentFactor;
                  for (final Entry<String,?> entry : this.entrySet()) {
                      if (needsComma) {
                          writer.write(',');
                      }
                      if (indentFactor > 0) {
                          writer.write('\n');
                      }
                      indent(writer, newIndent);
                      final String key = entry.getKey();
                      writer.write(quote(key));
                      writer.write(':');
                      if (indentFactor > 0) {
                          writer.write(' ');
                      }
                      try {
                          writeValue(writer, entry.getValue(), indentFactor, newIndent);
                      } catch (Exception e) {
                          throw new JSONException("Unable to write JSONObject value for key: " + key, e);
                      }
                      needsComma = true;
                  }
                  if (indentFactor > 0) {
                      writer.write('\n');
                  }
                  indent(writer, indent);
              }
              writer.write('}');
              return writer;
          } catch (IOException exception) {
              throw new JSONException(exception);
          }
      }
  
      /**
       * Returns a java.util.Map containing all of the entries in this object.
       * If an entry in the object is a JSONArray or JSONObject it will also
       * be converted.
       * <p>
       * Warning: This method assumes that the data structure is acyclical.
       *
       * @return a java.util.Map containing the entries of this object
       */
      public Map<String, Object> toMap() {
          Map<String, Object> results = new HashMap<String, Object>();
          for (Entry<String, Object> entry : this.entrySet()) {
              Object value;
              if (entry.getValue() == null || NULL.equals(entry.getValue())) {
                  value = null;
              } else if (entry.getValue() instanceof JSONObject) {
                  value = ((JSONObject) entry.getValue()).toMap();
              } else if (entry.getValue() instanceof JSONArray) {
                  value = ((JSONArray) entry.getValue()).toList();
              } else {
                  value = entry.getValue();
              }
              results.put(entry.getKey(), value);
          }
          return results;
      }
  
      /**
       * Create a new JSONException in a common format for incorrect conversions.
       * @param key name of the key
       * @param valueType the type of value being coerced to
       * @param cause optional cause of the coercion failure
       * @return JSONException that can be thrown.
       */
      private static JSONException wrongValueFormatException(
              String key,
              String valueType,
              Object value,
              Throwable cause) {
          if(value == null) {
  
              return new JSONException(
                      "JSONObject[" + quote(key) + "] is not a " + valueType + " (null)."
                      , cause);
          }
          // don't try to toString collections or known object types that could be large.
          if(value instanceof Map || value instanceof Iterable || value instanceof JSONObject) {
              return new JSONException(
                      "JSONObject[" + quote(key) + "] is not a " + valueType + " (" + value.getClass() + ")."
                      , cause);
          }
          return new JSONException(
                  "JSONObject[" + quote(key) + "] is not a " + valueType + " (" + value.getClass() + " : " + value + ")."
                  , cause);
      }
  
      /**
       * Create a new JSONException in a common format for recursive object definition.
       * @param key name of the key
       * @return JSONException that can be thrown.
       */
      private static JSONException recursivelyDefinedObjectException(String key) {
          return new JSONException(
              "JavaBean object contains recursively defined member variable of key " + quote(key)
          );
      }
  
      /**
       * For a prospective number, remove the leading zeros
       * @param value prospective number
       * @return number without leading zeros
       */
      private static String removeLeadingZerosOfNumber(String value){
          if (value.equals("-")){return value;}
          boolean negativeFirstChar = (value.charAt(0) == '-');
          int counter = negativeFirstChar ? 1:0;
          while (counter < value.length()){
              if (value.charAt(counter) != '0'){
                  if (negativeFirstChar) {return "-".concat(value.substring(counter));}
                  return value.substring(counter);
              }
              ++counter;
          }
          if (negativeFirstChar) {return "-0";}
          return "0";
      }
  }
  