001/*
002 * ====================================================================
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 *   http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing,
014 * software distributed under the License is distributed on an
015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
016 * KIND, either express or implied.  See the License for the
017 * specific language governing permissions and limitations
018 * under the License.
019 * ====================================================================
020 *
021 * This software consists of voluntary contributions made by many
022 * individuals on behalf of the Apache Software Foundation.  For more
023 * information on the Apache Software Foundation, please see
024 * <http://www.apache.org/>.
025 *
026 */
027package org.apache.http.nio.protocol;
028
029import java.io.IOException;
030
031import org.apache.http.ContentTooLongException;
032import org.apache.http.HttpEntity;
033import org.apache.http.HttpResponse;
034import org.apache.http.entity.ContentType;
035import org.apache.http.nio.ContentDecoder;
036import org.apache.http.nio.IOControl;
037import org.apache.http.nio.entity.ContentBufferEntity;
038import org.apache.http.nio.util.HeapByteBufferAllocator;
039import org.apache.http.nio.util.SimpleInputBuffer;
040import org.apache.http.protocol.HttpContext;
041import org.apache.http.util.Asserts;
042
043/**
044 * Basic implementation of {@link HttpAsyncResponseConsumer}. Please note that
045 * this consumer buffers response content in memory and should be used for
046 * relatively small response messages.
047 *
048 * @since 4.2
049 */
050public class BasicAsyncResponseConsumer extends AbstractAsyncResponseConsumer<HttpResponse> {
051
052    private static final int MAX_INITIAL_BUFFER_SIZE = 256 * 1024;
053
054    private volatile HttpResponse response;
055    private volatile SimpleInputBuffer buf;
056
057    public BasicAsyncResponseConsumer() {
058        super();
059    }
060
061    @Override
062    protected void onResponseReceived(final HttpResponse response) throws IOException {
063        this.response = response;
064    }
065
066    @Override
067    protected void onEntityEnclosed(
068            final HttpEntity entity, final ContentType contentType) throws IOException {
069        long len = entity.getContentLength();
070        if (len > Integer.MAX_VALUE) {
071            throw new ContentTooLongException("Entity content is too long: " + len);
072        }
073        if (len < 0) {
074            len = 4096;
075        }
076        final int initialBufferSize = Math.min((int) len, MAX_INITIAL_BUFFER_SIZE);
077        this.buf = new SimpleInputBuffer(initialBufferSize, new HeapByteBufferAllocator());
078        this.response.setEntity(new ContentBufferEntity(entity, this.buf));
079    }
080
081    @Override
082    protected void onContentReceived(
083            final ContentDecoder decoder, final IOControl ioctrl) throws IOException {
084        Asserts.notNull(this.buf, "Content buffer");
085        this.buf.consumeContent(decoder);
086    }
087
088    @Override
089    protected void releaseResources() {
090        this.response = null;
091        this.buf = null;
092    }
093
094    @Override
095    protected HttpResponse buildResult(final HttpContext context) {
096        return this.response;
097    }
098
099}