content: /*
   * Copyright 1999-2018 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.naming.web;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletRequestWrapper;
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * A request wrapper to override the parameters.
   * <p>
   * Referenced article is https://blog.csdn.net/xieyuooo/article/details/8447301
   *
   * @author nkorange
   * @since 0.8.0
   */
  public class OverrideParameterRequestWrapper extends HttpServletRequestWrapper {
  
      private Map<String, String[]> params = new HashMap<>();
  
      /**
       * Constructs a request object wrapping the given request.
       *
       * @param request The request to wrap
       * @throws IllegalArgumentException if the request is null
       */
      public OverrideParameterRequestWrapper(HttpServletRequest request) {
          super(request);
          this.params.putAll(request.getParameterMap());
      }
  
      public static OverrideParameterRequestWrapper buildRequest(HttpServletRequest request) {
          return new OverrideParameterRequestWrapper(request);
      }
  
      public static OverrideParameterRequestWrapper buildRequest(HttpServletRequest request, String name, String value) {
          OverrideParameterRequestWrapper requestWrapper = new OverrideParameterRequestWrapper(request);
          requestWrapper.addParameter(name, value);
          return requestWrapper;
      }
  
      public static OverrideParameterRequestWrapper buildRequest(HttpServletRequest request, Map<String, String[]> appendParameters) {
          OverrideParameterRequestWrapper requestWrapper = new OverrideParameterRequestWrapper(request);
          requestWrapper.params.putAll(appendParameters);
          return requestWrapper;
      }
  
      @Override
      public String getParameter(String name) {
          String[] values = params.get(name);
          if (values == null || values.length == 0) {
              return null;
          }
          return values[0];
      }
  
      @Override
      public Map<String, String[]> getParameterMap() {
          return params;
      }
  
      @Override
      public String[] getParameterValues(String name) {
          return params.get(name);
      }
  
      public void addParameter(String name, String value) {
          if (value != null) {
              params.put(name, new String[]{value});
          }
      }
  
  }
  