Java tutorial
/* * ==================================================================== * 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 com.apigee.sdk.apm.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.entity.AbstractHttpEntity; import com.apigee.sdk.apm.http.annotation.NotThreadSafe; import com.apigee.sdk.apm.http.client.cache.Resource; @NotThreadSafe 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); } public long getContentLength() { return -1; } public boolean isRepeatable() { return false; } public boolean isStreaming() { return true; } public InputStream getContent() throws IOException, IllegalStateException { return this.combinedStream; } public void writeTo(final OutputStream outstream) throws IOException { if (outstream == null) { throw new IllegalArgumentException("Output stream may not be null"); } InputStream instream = getContent(); try { int l; 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(); } } } }