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.util;
028
029import java.io.IOException;
030
031import org.apache.http.nio.ContentDecoder;
032
033/**
034 * Basic implementation of the {@link ContentInputBuffer} interface.
035 * <p>
036 * This class is not thread safe.
037 *
038 * @since 4.0
039 */
040public class SimpleInputBuffer extends ExpandableBuffer implements ContentInputBuffer {
041
042    private boolean endOfStream = false;
043
044    public SimpleInputBuffer(final int buffersize, final ByteBufferAllocator allocator) {
045        super(buffersize, allocator);
046    }
047
048    /**
049     * @since 4.3
050     */
051    public SimpleInputBuffer(final int buffersize) {
052        this(buffersize, HeapByteBufferAllocator.INSTANCE);
053    }
054
055    @Override
056    public void reset() {
057        this.endOfStream = false;
058        super.clear();
059    }
060
061    @Override
062    public int consumeContent(final ContentDecoder decoder) throws IOException {
063        setInputMode();
064        int totalRead = 0;
065        int bytesRead;
066        while ((bytesRead = decoder.read(this.buffer)) != -1) {
067            if (bytesRead == 0) {
068                if (!this.buffer.hasRemaining()) {
069                    expand();
070                } else {
071                    break;
072                }
073            } else {
074                totalRead += bytesRead;
075            }
076        }
077        if (bytesRead == -1 || decoder.isCompleted()) {
078            this.endOfStream = true;
079        }
080        return totalRead;
081    }
082
083    public boolean isEndOfStream() {
084        return !hasData() && this.endOfStream;
085    }
086
087    @Override
088    public int read() throws IOException {
089        if (isEndOfStream()) {
090            return -1;
091        }
092        setOutputMode();
093        return this.buffer.get() & 0xff;
094    }
095
096    @Override
097    public int read(final byte[] b, final int off, final int len) throws IOException {
098        if (isEndOfStream()) {
099            return -1;
100        }
101        if (b == null) {
102            return 0;
103        }
104        setOutputMode();
105        int chunk = len;
106        if (chunk > this.buffer.remaining()) {
107            chunk = this.buffer.remaining();
108        }
109        this.buffer.get(b, off, chunk);
110        return chunk;
111    }
112
113    public int read(final byte[] b) throws IOException {
114        if (isEndOfStream()) {
115            return -1;
116        }
117        if (b == null) {
118            return 0;
119        }
120        return read(b, 0, b.length);
121    }
122
123    public void shutdown() {
124        this.endOfStream = true;
125    }
126
127}