/**
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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 org.apache.hadoop.hbase.http;
  
  import javax.servlet.Filter;
  import javax.servlet.FilterChain;
  import javax.servlet.FilterConfig;
  import javax.servlet.ServletException;
  import javax.servlet.ServletRequest;
  import javax.servlet.ServletResponse;
  import javax.servlet.http.HttpServletResponse;
  import java.io.IOException;
  
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.HBaseInterfaceAudience;
  
  @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
  public class ClickjackingPreventionFilter implements Filter {
  
      private FilterConfig filterConfig;
  
      @Override
      public void init(FilterConfig filterConfig) throws ServletException {
          this.filterConfig = filterConfig;
      }
  
      @Override
      public void doFilter(ServletRequest req, ServletResponse res,
                           FilterChain chain)
              throws IOException, ServletException {
          HttpServletResponse httpRes = (HttpServletResponse) res;
          httpRes.addHeader("X-Frame-Options", filterConfig.getInitParameter("xframeoptions"));
          chain.doFilter(req, res);
      }
  
      @Override
      public void destroy() {
      }
  
  }