content: /**
   * Copyright (C) 2012 the original author or authors.
   *
   * 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 co.jirm.core.util;
  
  import java.io.UnsupportedEncodingException;
  import java.net.URI;
  import java.net.URLDecoder;
  import java.net.URLEncoder;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  import java.util.Map;
  import java.util.Scanner;
  
  import com.google.common.collect.Lists;
  import com.google.common.collect.Maps;
  
  
  
  public class JirmUrlEncodedUtils {
  
      private static final String PARAMETER_SEPARATOR = "&";
      private static final String NAME_VALUE_SEPARATOR = "=";
  
      /**
       * Returns a list of {@link NameValuePair NameValuePairs} as built from the
       * URI's query portion. For example, a URI of
       * http://example.org/path/to/file?a=1&b=2&c=3 would return a list of three
       * NameValuePairs, one for a=1, one for b=2, and one for c=3.
       * <p>
       * This is typically useful while parsing an HTTP PUT.
       *
       * @param uri
       *            uri to parse
       * @param encoding
       *            encoding to use while parsing the query
       */
      public static List <NameValuePair> parse(final URI uri, final String encoding) {
          List <NameValuePair> result = Collections.emptyList();
          final String query = uri.getRawQuery();
          if (query != null && query.length() > 0) {
              result = new ArrayList <NameValuePair>();
              parse(result, new Scanner(query), encoding);
          }
          return result;
      }
      
      public static Map<String, List<String>> parseParameters(final URI uri, final String encoding) {
          List <NameValuePair> result = parse(uri, encoding);
          Map<String,List<String>> m = Maps.newLinkedHashMap();
          for (NameValuePair nvp : result) {
          	List<String> list = m.get(nvp.getName());
          	if (list == null) { 
          		list = Lists.newArrayList();
          		m.put(nvp.getName(), list);
          	}
          	list.add(nvp.getValue());
          }
          return m;
      }
  
      /**
       * Adds all parameters within the Scanner to the list of
       * <code>parameters</code>, as encoded by <code>encoding</code>. For
       * example, a scanner containing the string <code>a=1&b=2&c=3</code> would
       * add the {@link NameValuePair NameValuePairs} a=1, b=2, and c=3 to the
       * list of parameters.
       *
       * @param parameters
       *            List to add parameters to.
       * @param scanner
       *            Input that contains the parameters to parse.
       * @param encoding
       *            Encoding to use when decoding the parameters.
       */
      public static void parse (
              final List <NameValuePair> parameters,
              final Scanner scanner,
              final String encoding) {
          scanner.useDelimiter(PARAMETER_SEPARATOR);
          while (scanner.hasNext()) {
              final String[] nameValue = scanner.next().split(NAME_VALUE_SEPARATOR);
              if (nameValue.length == 0 || nameValue.length > 2)
                  throw new IllegalArgumentException("bad parameter");
  
              final String name = decode(nameValue[0], encoding);
              String value = null;
              if (nameValue.length == 2)
                  value = decode(nameValue[1], encoding);
              parameters.add(new NameValuePair(name, value));
          }
      }
      
      public static class NameValuePair {
      	private final String name;
      	private final String value;
  		private NameValuePair(String name, String value) {
  			super();
  			this.name = name;
  			this.value = value;
  		}
  		
  		public String getName() {
  			return name;
  		}
  		
  		public String getValue() {
  			return value;
  		}
      	
      }
  
      /**
       * Returns a String that is suitable for use as an <code>application/x-www-form-urlencoded</code>
       * list of parameters in an HTTP PUT or HTTP POST.
       *
       * @param parameters  The parameters to include.
       * @param encoding The encoding to use.
       */
      public static String format (
              final List <? extends NameValuePair> parameters,
              final String encoding) {
          final StringBuilder result = new StringBuilder();
          for (final NameValuePair parameter : parameters) {
              final String encodedName = encode(parameter.getName(), encoding);
              final String value = parameter.getValue();
              final String encodedValue = value != null ? encode(value, encoding) : "";
              if (result.length() > 0)
                  result.append(PARAMETER_SEPARATOR);
              result.append(encodedName);
              result.append(NAME_VALUE_SEPARATOR);
              result.append(encodedValue);
          }
          return result.toString();
      }
  
      private static String decode (final String content, final String encoding) {
          try {
              return URLDecoder.decode(content,
                      encoding != null ? encoding : "UTF-8");
          } catch (UnsupportedEncodingException problem) {
              throw new IllegalArgumentException(problem);
          }
      }
  
      private static String encode (final String content, final String encoding) {
          try {
              return URLEncoder.encode(content,
                      encoding != null ? encoding : "UTF-8");
          } catch (UnsupportedEncodingException problem) {
              throw new IllegalArgumentException(problem);
          }
      }
  }
  