content: /*
   * Copyright 1999-2023 Alibaba Group Holding Ltd.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package com.alibaba.nacos.common.packagescan.util;
  
  import java.lang.reflect.Array;
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.Map;
  import java.util.Optional;
  import java.util.StringJoiner;
  
  /**
   * Copy from https://github.com/spring-projects/spring-framework.git, with less modifications
   * Miscellaneous object utility methods.
   *
   * <p>Mainly for internal use within the framework.
   *
   * <p>Thanks to Alex Ruiz for contributing several enhancements to this class!
   *
   * @author Juergen Hoeller
   * @author Keith Donald
   * @author Rod Johnson
   * @author Rob Harrop
   * @author Chris Beams
   * @author Sam Brannen
   * @since 19.03.2004
   */
  public abstract class AbstractObjectUtils {
  
      private AbstractObjectUtils() {
      }
  
      private static final int INITIAL_HASH = 7;
  
      private static final int MULTIPLIER = 31;
  
      private static final String EMPTY_STRING = "";
  
      private static final String NULL_STRING = "null";
  
      private static final String ARRAY_START = "{";
  
      private static final String ARRAY_END = "}";
  
      private static final String EMPTY_ARRAY = ARRAY_START + ARRAY_END;
  
      private static final String ARRAY_ELEMENT_SEPARATOR = ", ";
  
      private static final Object[] EMPTY_OBJECT_ARRAY = new Object[0];
  
      /**
       * Return whether the given throwable is a checked exception:
       * that is, neither a RuntimeException nor an Error.
       *
       * @param ex the throwable to check
       * @return whether the throwable is a checked exception
       * @see Exception
       * @see RuntimeException
       * @see Error
       */
      public static boolean isCheckedException(Throwable ex) {
          return !(ex instanceof RuntimeException || ex instanceof Error);
      }
  
      /**
       * Check whether the given exception is compatible with the specified
       * exception types, as declared in a throws clause.
       *
       * @param ex                 the exception to check
       * @param declaredExceptions the exception types declared in the throws clause
       * @return whether the given exception is compatible
       */
      public static boolean isCompatibleWithThrowsClause(Throwable ex, Class<?>... declaredExceptions) {
          if (!isCheckedException(ex)) {
              return true;
          }
          if (declaredExceptions != null) {
              for (Class<?> declaredException : declaredExceptions) {
                  if (declaredException.isInstance(ex)) {
                      return true;
                  }
              }
          }
          return false;
      }
  
      /**
       * Determine whether the given object is an array:
       * either an Object array or a primitive array.
       *
       * @param obj the object to check
       */
      public static boolean isArray(Object obj) {
          return (obj != null && obj.getClass().isArray());
      }
  
      /**
       * Determine whether the given array is empty:
       * i.e. {@code null} or of zero length.
       *
       * @param array the array to check
       * @see #isEmpty(Object)
       */
      public static boolean isEmpty(Object[] array) {
          return (array == null || array.length == 0);
      }
  
      /**
       * Determine whether the given object is empty.
       *
       * <p>This method supports the following object types.
       * <ul>
       * <li>{@code Optional}: considered empty if not {@link Optional#isPresent()}</li>
       * <li>{@code Array}: considered empty if its length is zero</li>
       * <li>{@link CharSequence}: considered empty if its length is zero</li>
       * </ul>
       *
       * <p>If the given object is non-null and not one of the aforementioned
       * supported types, this method returns {@code false}.
       *
       * @param obj the object to check
       * @return {@code true} if the object is {@code null} or <em>empty</em>
       * @see Optional#isPresent()
       * @see AbstractObjectUtils#isEmpty(Object[])
       * @since 4.2
       */
      public static boolean isEmpty(Object obj) {
          if (obj == null) {
              return true;
          }
  
          if (obj instanceof Optional) {
              return !((Optional<?>) obj).isPresent();
          }
          if (obj instanceof CharSequence) {
              return ((CharSequence) obj).length() == 0;
          }
          if (obj.getClass().isArray()) {
              return Array.getLength(obj) == 0;
          }
          if (obj instanceof Collection) {
              return ((Collection<?>) obj).isEmpty();
          }
          if (obj instanceof Map) {
              return ((Map<?, ?>) obj).isEmpty();
          }
  
          // else
          return false;
      }
  
      /**
       * Unwrap the given object which is potentially a {@link Optional}.
       *
       * @param obj the candidate object
       * @return either the value held within the {@code Optional}, {@code null}
       * if the {@code Optional} is empty, or simply the given object as-is
       * @since 5.0
       */
  
      public static Object unwrapOptional(Object obj) {
          if (obj instanceof Optional) {
              Optional<?> optional = (Optional<?>) obj;
              if (!optional.isPresent()) {
                  return null;
              }
              Object result = optional.get();
              AbstractAssert.isTrue(!(result instanceof Optional), "Multi-level Optional usage not supported");
              return result;
          }
          return obj;
      }
  
      /**
       * Check whether the given array contains the given element.
       *
       * @param array   the array to check (may be {@code null},
       *                in which case the return value will always be {@code false})
       * @param element the element to check for
       * @return whether the element has been found in the given array
       */
      public static boolean containsElement(Object[] array, Object element) {
          if (array == null) {
              return false;
          }
          for (Object arrayEle : array) {
              if (nullSafeEquals(arrayEle, element)) {
                  return true;
              }
          }
          return false;
      }
  
      /**
       * Check whether the given array of enum constants contains a constant with the given name,
       * ignoring case when determining a match.
       *
       * @param enumValues the enum values to check, typically obtained via {@code MyEnum.values()}
       * @param constant   the constant name to find (must not be null or empty string)
       * @return whether the constant has been found in the given array
       */
      public static boolean containsConstant(Enum<?>[] enumValues, String constant) {
          return containsConstant(enumValues, constant, false);
      }
  
      /**
       * Check whether the given array of enum constants contains a constant with the given name.
       *
       * @param enumValues    the enum values to check, typically obtained via {@code MyEnum.values()}
       * @param constant      the constant name to find (must not be null or empty string)
       * @param caseSensitive whether case is significant in determining a match
       * @return whether the constant has been found in the given array
       */
      public static boolean containsConstant(Enum<?>[] enumValues, String constant, boolean caseSensitive) {
          for (Enum<?> candidate : enumValues) {
              if (caseSensitive ? candidate.toString().equals(constant) :
                      candidate.toString().equalsIgnoreCase(constant)) {
                  return true;
              }
          }
          return false;
      }
  
      /**
       * Case insensitive alternative to {@link Enum#valueOf(Class, String)}.
       *
       * @param <E>        the concrete Enum type
       * @param enumValues the array of all Enum constants in question, usually per {@code Enum.values()}
       * @param constant   the constant to get the enum value of
       * @throws IllegalArgumentException if the given constant is not found in the given array
       *                                  of enum values. Use {@link #containsConstant(Enum[], String)} as a guard to avoid this exception.
       */
      public static <E extends Enum<?>> E caseInsensitiveValueOf(E[] enumValues, String constant) {
          for (E candidate : enumValues) {
              if (candidate.toString().equalsIgnoreCase(constant)) {
                  return candidate;
              }
          }
          throw new IllegalArgumentException("Constant [" + constant + "] does not exist in enum type "
                  +
                  enumValues.getClass().getComponentType().getName());
      }
  
      /**
       * Append the given object to the given array, returning a new array
       * consisting of the input array contents plus the given object.
       *
       * @param array the array to append to (can be {@code null})
       * @param obj   the object to append
       * @return the new array (of the same component type; never {@code null})
       */
      public static <A, O extends A> A[] addObjectToArray(A[] array, O obj) {
          Class<?> compType = Object.class;
          if (array != null) {
              compType = array.getClass().getComponentType();
          } else if (obj != null) {
              compType = obj.getClass();
          }
          int newArrLength = (array != null ? array.length + 1 : 1);
          @SuppressWarnings("unchecked")
          A[] newArr = (A[]) Array.newInstance(compType, newArrLength);
          if (array != null) {
              System.arraycopy(array, 0, newArr, 0, array.length);
          }
          newArr[newArr.length - 1] = obj;
          return newArr;
      }
  
      /**
       * Convert the given array (which may be a primitive array) to an
       * object array (if necessary of primitive wrapper objects).
       *
       * <p>A {@code null} source value will be converted to an
       * empty Object array.
       *
       * @param source the (potentially primitive) array
       * @return the corresponding object array (never {@code null})
       * @throws IllegalArgumentException if the parameter is not an array
       */
      public static Object[] toObjectArray(Object source) {
          if (source instanceof Object[]) {
              return (Object[]) source;
          }
          if (source == null) {
              return EMPTY_OBJECT_ARRAY;
          }
          if (!source.getClass().isArray()) {
              throw new IllegalArgumentException("Source is not an array: " + source);
          }
          int length = Array.getLength(source);
          if (length == 0) {
              return EMPTY_OBJECT_ARRAY;
          }
          Class<?> wrapperType = Array.get(source, 0).getClass();
          Object[] newArray = (Object[]) Array.newInstance(wrapperType, length);
          for (int i = 0; i < length; i++) {
              newArray[i] = Array.get(source, i);
          }
          return newArray;
      }
  
      //---------------------------------------------------------------------
      // Convenience methods for content-based equality/hash-code handling
      //---------------------------------------------------------------------
  
      /**
       * Determine if the given objects are equal, returning {@code true} if
       * both are {@code null} or {@code false} if only one is {@code null}.
       *
       * <p>Compares arrays with {@code Arrays.equals}, performing an equality
       * check based on the array elements rather than the array reference.
       *
       * @param o1 first Object to compare
       * @param o2 second Object to compare
       * @return whether the given objects are equal
       * @see Object#equals(Object)
       * @see Arrays#equals
       */
      public static boolean nullSafeEquals(Object o1, Object o2) {
          if (o1 == o2) {
              return true;
          }
          if (o1 == null || o2 == null) {
              return false;
          }
          if (o1.equals(o2)) {
              return true;
          }
          if (o1.getClass().isArray() && o2.getClass().isArray()) {
              return arrayEquals(o1, o2);
          }
          return false;
      }
  
      /**
       * Compare the given arrays with {@code Arrays.equals}, performing an equality
       * check based on the array elements rather than the array reference.
       *
       * @param o1 first array to compare
       * @param o2 second array to compare
       * @return whether the given objects are equal
       * @see #nullSafeEquals(Object, Object)
       * @see Arrays#equals
       */
      private static boolean arrayEquals(Object o1, Object o2) {
          if (o1 instanceof Object[] && o2 instanceof Object[]) {
              return Arrays.equals((Object[]) o1, (Object[]) o2);
          }
          if (o1 instanceof boolean[] && o2 instanceof boolean[]) {
              return Arrays.equals((boolean[]) o1, (boolean[]) o2);
          }
          if (o1 instanceof byte[] && o2 instanceof byte[]) {
              return Arrays.equals((byte[]) o1, (byte[]) o2);
          }
          if (o1 instanceof char[] && o2 instanceof char[]) {
              return Arrays.equals((char[]) o1, (char[]) o2);
          }
          if (o1 instanceof double[] && o2 instanceof double[]) {
              return Arrays.equals((double[]) o1, (double[]) o2);
          }
          if (o1 instanceof float[] && o2 instanceof float[]) {
              return Arrays.equals((float[]) o1, (float[]) o2);
          }
          if (o1 instanceof int[] && o2 instanceof int[]) {
              return Arrays.equals((int[]) o1, (int[]) o2);
          }
          if (o1 instanceof long[] && o2 instanceof long[]) {
              return Arrays.equals((long[]) o1, (long[]) o2);
          }
          if (o1 instanceof short[] && o2 instanceof short[]) {
              return Arrays.equals((short[]) o1, (short[]) o2);
          }
          return false;
      }
  
      /**
       * Return as hash code for the given object; typically the value of
       * {@code Object#hashCode()}}. If the object is an array,
       * this method will delegate to any of the {@code nullSafeHashCode}
       * methods for arrays in this class. If the object is {@code null},
       * this method returns 0.
       *
       * @see Object#hashCode()
       * @see #nullSafeHashCode(Object[])
       * @see #nullSafeHashCode(boolean[])
       * @see #nullSafeHashCode(byte[])
       * @see #nullSafeHashCode(char[])
       * @see #nullSafeHashCode(double[])
       * @see #nullSafeHashCode(float[])
       * @see #nullSafeHashCode(int[])
       * @see #nullSafeHashCode(long[])
       * @see #nullSafeHashCode(short[])
       */
      public static int nullSafeHashCode(Object obj) {
          if (obj == null) {
              return 0;
          }
          if (obj.getClass().isArray()) {
              if (obj instanceof Object[]) {
                  return nullSafeHashCode((Object[]) obj);
              }
              if (obj instanceof boolean[]) {
                  return nullSafeHashCode((boolean[]) obj);
              }
              if (obj instanceof byte[]) {
                  return nullSafeHashCode((byte[]) obj);
              }
              if (obj instanceof char[]) {
                  return nullSafeHashCode((char[]) obj);
              }
              if (obj instanceof double[]) {
                  return nullSafeHashCode((double[]) obj);
              }
              if (obj instanceof float[]) {
                  return nullSafeHashCode((float[]) obj);
              }
              if (obj instanceof int[]) {
                  return nullSafeHashCode((int[]) obj);
              }
              if (obj instanceof long[]) {
                  return nullSafeHashCode((long[]) obj);
              }
              if (obj instanceof short[]) {
                  return nullSafeHashCode((short[]) obj);
              }
          }
          return obj.hashCode();
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(Object[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (Object element : array) {
              hash = MULTIPLIER * hash + nullSafeHashCode(element);
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(boolean[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (boolean element : array) {
              hash = MULTIPLIER * hash + Boolean.hashCode(element);
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(byte[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (byte element : array) {
              hash = MULTIPLIER * hash + element;
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(char[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (char element : array) {
              hash = MULTIPLIER * hash + element;
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(double[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (double element : array) {
              hash = MULTIPLIER * hash + Double.hashCode(element);
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(float[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (float element : array) {
              hash = MULTIPLIER * hash + Float.hashCode(element);
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(int[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (int element : array) {
              hash = MULTIPLIER * hash + element;
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(long[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (long element : array) {
              hash = MULTIPLIER * hash + Long.hashCode(element);
          }
          return hash;
      }
  
      /**
       * Return a hash code based on the contents of the specified array.
       * If {@code array} is {@code null}, this method returns 0.
       */
      public static int nullSafeHashCode(short[] array) {
          if (array == null) {
              return 0;
          }
          int hash = INITIAL_HASH;
          for (short element : array) {
              hash = MULTIPLIER * hash + element;
          }
          return hash;
      }
  
      /**
       * Return the same value as {@link Boolean#hashCode(boolean)}}.
       *
       * @deprecated as of Spring Framework 5.0, in favor of the native JDK 8 variant
       */
      @Deprecated
      public static int hashCode(boolean bool) {
          return Boolean.hashCode(bool);
      }
  
      /**
       * Return the same value as {@link Double#hashCode(double)}}.
       *
       * @deprecated as of Spring Framework 5.0, in favor of the native JDK 8 variant
       */
      @Deprecated
      public static int hashCode(double dbl) {
          return Double.hashCode(dbl);
      }
  
      /**
       * Return the same value as {@link Float#hashCode(float)}}.
       *
       * @deprecated as of Spring Framework 5.0, in favor of the native JDK 8 variant
       */
      @Deprecated
      public static int hashCode(float flt) {
          return Float.hashCode(flt);
      }
  
      /**
       * Return the same value as {@link Long#hashCode(long)}}.
       *
       * @deprecated as of Spring Framework 5.0, in favor of the native JDK 8 variant
       */
      @Deprecated
      public static int hashCode(long lng) {
          return Long.hashCode(lng);
      }
  
      //---------------------------------------------------------------------
      // Convenience methods for toString output
      //---------------------------------------------------------------------
  
      /**
       * Return a String representation of an object's overall identity.
       *
       * @param obj the object (may be {@code null})
       * @return the object's identity as String representation,
       * or an empty String if the object was {@code null}
       */
      public static String identityToString(Object obj) {
          if (obj == null) {
              return EMPTY_STRING;
          }
          return obj.getClass().getName() + "@" + getIdentityHexString(obj);
      }
  
      /**
       * Return a hex String form of an object's identity hash code.
       *
       * @param obj the object
       * @return the object's identity code in hex notation
       */
      public static String getIdentityHexString(Object obj) {
          return Integer.toHexString(System.identityHashCode(obj));
      }
  
      /**
       * Return a content-based String representation if {@code obj} is
       * not {@code null}; otherwise returns an empty String.
       *
       * <p>Differs from {@link #nullSafeToString(Object)} in that it returns
       * an empty String rather than "null" for a {@code null} value.
       *
       * @param obj the object to build a display String for
       * @return a display String representation of {@code obj}
       * @see #nullSafeToString(Object)
       */
      public static String getDisplayString(Object obj) {
          if (obj == null) {
              return EMPTY_STRING;
          }
          return nullSafeToString(obj);
      }
  
      /**
       * Determine the class name for the given object.
       *
       * <p>Returns a {@code "null"} String if {@code obj} is {@code null}.
       *
       * @param obj the object to introspect (may be {@code null})
       * @return the corresponding class name
       */
      public static String nullSafeClassName(Object obj) {
          return (obj != null ? obj.getClass().getName() : NULL_STRING);
      }
  
      /**
       * Return a String representation of the specified Object.
       *
       * <p>Builds a String representation of the contents in case of an array.
       * Returns a {@code "null"} String if {@code obj} is {@code null}.
       *
       * @param obj the object to build a String representation for
       * @return a String representation of {@code obj}
       */
      public static String nullSafeToString(Object obj) {
          if (obj == null) {
              return NULL_STRING;
          }
          if (obj instanceof String) {
              return (String) obj;
          }
          if (obj instanceof Object[]) {
              return nullSafeToString((Object[]) obj);
          }
          if (obj instanceof boolean[]) {
              return nullSafeToString((boolean[]) obj);
          }
          if (obj instanceof byte[]) {
              return nullSafeToString((byte[]) obj);
          }
          if (obj instanceof char[]) {
              return nullSafeToString((char[]) obj);
          }
          if (obj instanceof double[]) {
              return nullSafeToString((double[]) obj);
          }
          if (obj instanceof float[]) {
              return nullSafeToString((float[]) obj);
          }
          if (obj instanceof int[]) {
              return nullSafeToString((int[]) obj);
          }
          if (obj instanceof long[]) {
              return nullSafeToString((long[]) obj);
          }
          if (obj instanceof short[]) {
              return nullSafeToString((short[]) obj);
          }
          String str = obj.toString();
          return (str != null ? str : EMPTY_STRING);
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(Object[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (Object o : array) {
              stringJoiner.add(String.valueOf(o));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(boolean[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (boolean b : array) {
              stringJoiner.add(String.valueOf(b));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(byte[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (byte b : array) {
              stringJoiner.add(String.valueOf(b));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(char[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (char c : array) {
              stringJoiner.add('\'' + String.valueOf(c) + '\'');
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(double[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (double d : array) {
              stringJoiner.add(String.valueOf(d));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(float[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (float f : array) {
              stringJoiner.add(String.valueOf(f));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(int[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (int i : array) {
              stringJoiner.add(String.valueOf(i));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(long[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (long l : array) {
              stringJoiner.add(String.valueOf(l));
          }
          return stringJoiner.toString();
      }
  
      /**
       * Return a String representation of the contents of the specified array.
       *
       * <p>The String representation consists of a list of the array's elements,
       * enclosed in curly braces ({@code "{}"}). Adjacent elements are separated
       * by the characters {@code ", "} (a comma followed by a space).
       * Returns a {@code "null"} String if {@code array} is {@code null}.
       *
       * @param array the array to build a String representation for
       * @return a String representation of {@code array}
       */
      public static String nullSafeToString(short[] array) {
          if (array == null) {
              return NULL_STRING;
          }
          int length = array.length;
          if (length == 0) {
              return EMPTY_ARRAY;
          }
          StringJoiner stringJoiner = new StringJoiner(ARRAY_ELEMENT_SEPARATOR, ARRAY_START, ARRAY_END);
          for (short s : array) {
              stringJoiner.add(String.valueOf(s));
          }
          return stringJoiner.toString();
      }
  
  }
  