/* $Id: CircularByteBuffer.java 742162 2009-02-08 20:54:34Z dixson $
*
* Copyright 2007-2008 Cisco Systems Inc.
*
* Licensed 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 etch.util;
import java.io.EOFException;
import java.nio.BufferOverflowException;
/**
* Description of CircularByteBuffer.
*/
public class CircularByteBuffer extends ByteBuffer
{
/**
* Constructs the CircularByteBuffer.
*
* @param size
*/
public CircularByteBuffer( int size )
{
this.size = size;
buf = new byte[size];
}
private final int size;
private final byte[] buf;
private int length;
private int nextGet;
private int nextPut;
@Override
public int size()
{
return size;
}
@Override
public int length()
{
return length;
}
@Override
public void clear()
{
length = 0;
nextGet = 0;
nextPut = 0;
}
@Override
public byte get() throws EOFException
{
if (isEmpty())
throw new EOFException();
length--;
byte b = buf[nextGet++];
if (nextGet >= size)
nextGet = 0;
return b;
}
@Override
public void put( byte b ) throws BufferOverflowException
{
if (isFull())
throw new BufferOverflowException();
length++;
buf[nextPut++] = b;
if (nextPut >= size)
nextPut = 0;
}
}