001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package org.apache.hadoop.lib.wsrs;
020    
021    import org.apache.hadoop.io.IOUtils;
022    
023    import javax.ws.rs.core.StreamingOutput;
024    import java.io.IOException;
025    import java.io.InputStream;
026    import java.io.OutputStream;
027    
028    public class InputStreamEntity implements StreamingOutput {
029      private InputStream is;
030      private long offset;
031      private long len;
032    
033      public InputStreamEntity(InputStream is, long offset, long len) {
034        this.is = is;
035        this.offset = offset;
036        this.len = len;
037      }
038    
039      public InputStreamEntity(InputStream is) {
040        this(is, 0, -1);
041      }
042    
043      @Override
044      public void write(OutputStream os) throws IOException {
045        long skipped = is.skip(offset);
046        if (skipped < offset) {
047          throw new IOException("Requested offset beyond stream size");
048        }
049        if (len == -1) {
050          IOUtils.copyBytes(is, os, 4096, true);
051        } else {
052          IOUtils.copyBytes(is, os, len, true);
053        }
054      }
055    }