org.apache.hadoop.io.DataInputByteBuffer Maven / Gradle / Ivy
/**
* 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.
*/
package org.apache.hadoop.io;
import java.io.DataInputStream;
import java.io.InputStream;
import java.nio.ByteBuffer;
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();
}
}