001package org.cache2k.storage;
002
003/*
004 * #%L
005 * cache2k core package
006 * %%
007 * Copyright (C) 2000 - 2015 headissue GmbH, Munich
008 * %%
009 * This program is free software: you can redistribute it and/or modify
010 * it under the terms of the GNU General Public License as
011 * published by the Free Software Foundation, either version 3 of the 
012 * License, or (at your option) any later version.
013 * 
014 * This program is distributed in the hope that it will be useful,
015 * but WITHOUT ANY WARRANTY; without even the implied warranty of
016 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
017 * GNU General Public License for more details.
018 * 
019 * You should have received a copy of the GNU General Public 
020 * License along with this program.  If not, see
021 * <http://www.gnu.org/licenses/gpl-3.0.html>.
022 * #L%
023 */
024
025import java.io.IOException;
026import java.io.InputStream;
027import java.nio.ByteBuffer;
028
029/**
030 * InputStream wrapper that reads directly from a bytebuffer.
031 *
032 * Credits: inspired by the stackoverflow question and adapted to my coding style.
033 *
034 * @author Jens Wilke; created: 2014-03-28
035 */
036public class ByteBufferInputStream extends InputStream {
037
038  ByteBuffer byteBuffer;
039
040  public ByteBufferInputStream(ByteBuffer buf) {
041    byteBuffer = buf;
042}
043
044  public int read() throws IOException {
045    if (!byteBuffer.hasRemaining()) {
046      return -1;
047    }
048    return byteBuffer.get() & 0x0ff;
049  }
050
051  public int read(byte[] bytes, int off, int len) throws IOException {
052    if (!byteBuffer.hasRemaining()) {
053      return -1;
054    }
055    len = Math.min(len, byteBuffer.remaining());
056    byteBuffer.get(bytes, off, len);
057    return len;
058  }
059
060}