| package org.apache.hadoop.io; |
| |
| import java.io.DataInputStream; |
| import java.io.InputStream; |
| import java.nio.ByteBuffer; |
| import java.util.LinkedList; |
| import java.util.List; |
| |
| public class DataInputByteBuffer extends DataInputStream { |
| |
| private static class Buffer extends InputStream { |
| private final byte[] scratch = new byte[1]; |
| ByteBuffer[] buffers = new ByteBuffer[0]; |
| int bidx, pos, length; |
| @Override |
| public int read() { |
| if (-1 == read(scratch, 0, 1)) { |
| return -1; |
| } |
| return scratch[0] & 0xFF; |
| } |
| @Override |
| public int read(byte[] b, int off, int len) { |
| if (bidx >= buffers.length) { |
| return -1; |
| } |
| int cur = 0; |
| do { |
| int rem = Math.min(len, buffers[bidx].remaining()); |
| buffers[bidx].get(b, off, rem); |
| cur += rem; |
| off += rem; |
| len -= rem; |
| } while (len > 0 && ++bidx < buffers.length); |
| pos += cur; |
| return cur; |
| } |
| public void reset(ByteBuffer[] buffers) { |
| bidx = pos = length = 0; |
| this.buffers = buffers; |
| for (ByteBuffer b : buffers) { |
| length += b.remaining(); |
| } |
| } |
| public int getPosition() { |
| return pos; |
| } |
| public int getLength() { |
| return length; |
| } |
| public ByteBuffer[] getData() { |
| return buffers; |
| } |
| } |
| |
| private Buffer buffers; |
| |
| public DataInputByteBuffer() { |
| this(new Buffer()); |
| } |
| |
| private DataInputByteBuffer(Buffer buffers) { |
| super(buffers); |
| this.buffers = buffers; |
| } |
| |
| public void reset(ByteBuffer... input) { |
| buffers.reset(input); |
| } |
| |
| public ByteBuffer[] getData() { |
| return buffers.getData(); |
| } |
| |
| public int getPosition() { |
| return buffers.getPosition(); |
| } |
| |
| public int getLength() { |
| return buffers.getLength(); |
| } |
| } |