/**

  * Copyright (C) 2013 Matthias Langer

  *

  * 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 at.ipsquare.commons.servlet;

 import java.io.IOException;

 import javax.servlet.Filter;

 import javax.servlet.FilterChain;

 import javax.servlet.FilterConfig;

 import javax.servlet.ServletException;

 import javax.servlet.ServletRequest;

 import javax.servlet.ServletResponse;

 /**

  * A filter that consistently sets the request encoding.

  * 

  * @since 2.1.0

  * @author Matthias Langer

  */

 public class RequestEncodingFilter implements Filter

 {

     private String encoding;

     private boolean force;

     private RequestMatcher matcher;

     /**

      * The init parameter name for the encoding (defaults to UTF-8).

      */

     public static final String INIT_PARAM_NAME_ENCODING = "encoding";

     /**

      * The init parameter name for the force encoding property (defaults to false).

      */

     public static final String INIT_PARAM_NAME_FORCE = "forceEncoding";

     @Override

     public void init(FilterConfig cfg) throws ServletException

     {

         encoding = cfg.getInitParameter(INIT_PARAM_NAME_ENCODING);

         force = Boolean.parseBoolean(cfg.getInitParameter(INIT_PARAM_NAME_FORCE));

         matcher = PathPatternRequestMatcher.fromFilterConfig(cfg);

         if(encoding == null)

             encoding = "UTF-8";

     }

     @Override

     public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException

     {

         if(matcher.matches(req))

         {

             if(force || req.getCharacterEncoding() == null)

                 req.setCharacterEncoding(encoding);

         }

         chain.doFilter(req, res);

     }

     @Override

     public void destroy()

     {

     }

 }