/*
    * ====================================================================
    * 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   */
  package org.apache.http.impl.client.cache;
  
  import java.io.FilterInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  import java.io.SequenceInputStream;
  
  import org.apache.http.client.cache.Resource;
  import org.apache.http.entity.AbstractHttpEntity;
  import org.apache.http.util.Args;
  
  class CombinedEntity extends AbstractHttpEntity {
  
      private final Resource resource;
      private final InputStream combinedStream;
  
      CombinedEntity(final Resource resource, final InputStream inStream) throws IOException {
          super();
          this.resource = resource;
          this.combinedStream = new SequenceInputStream(
                  new ResourceStream(resource.getInputStream()), inStream);
      }
  
      @Override
      public long getContentLength() {
          return -1;
      }
  
      @Override
      public boolean isRepeatable() {
          return false;
      }
  
      @Override
      public boolean isStreaming() {
          return true;
      }
  
      @Override
      public InputStream getContent() throws IOException, IllegalStateException {
          return this.combinedStream;
      }
  
      @Override
      public void writeTo(final OutputStream outStream) throws IOException {
          Args.notNull(outStream, "Output stream");
          final InputStream inStream = getContent();
          try {
              int l;
              final byte[] tmp = new byte[2048];
              while ((l = inStream.read(tmp)) != -1) {
                  outStream.write(tmp, 0, l);
              }
          } finally {
              inStream.close();
          }
      }
  
      private void dispose() {
          this.resource.dispose();
      }
  
      class ResourceStream extends FilterInputStream {
  
          protected ResourceStream(final InputStream in) {
              super(in);
          }
  
          @Override
          public void close() throws IOException {
              try {
                  super.close();
             } finally {
                 dispose();
             }
         }
 
     }
 
 }