flash.swf.RandomAccessBuffer Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of swfutils Show documentation
The Apache Royale Compiler SWF Utility classes
The newest version!
/*
 *
 *  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 flash.swf;

import java.io.ByteArrayOutputStream;
import java.io.OutputStream;
import java.io.IOException;

/**
 * Extends ByteArrayOutputStream by adding support for a position.
 */
public class RandomAccessBuffer extends ByteArrayOutputStream
{
	protected int pos = 0;

    /**
     * Init an 1k buffer (BAOS default is 32 bytes, so this should be better)
     */
    public RandomAccessBuffer()
    {
        super(1024);
    }
    
    public RandomAccessBuffer(int bufferSize)
    {
        super(bufferSize);
    }
    
	final public int getPos()
	{
		return pos;
	}

	final public void setPos(int pos)
	{
		this.pos = pos;
	}

    // we override this so we can declare the signature w/out any exceptions
    final public synchronized void write(byte[] b)
    {
        this.write(b, 0, b.length);
    }

	final public synchronized void write(byte[] b, int off, int len)
	{
		if (pos > count)
		{
			byte[] zeros = new byte[pos - count];
			super.write(zeros, 0, zeros.length);
			pos = count;
		}
		else if (pos < count)
		{
			int overlap = Math.min(count - pos, len);
			System.arraycopy(b, off, buf, pos, overlap);
			pos += overlap;
			off += overlap;
			len -= overlap;
		}
		super.write(b, off, len);
		pos += len;
	}

	final public synchronized void readFully(byte[] bytes)
	{
		int len = bytes.length;
		if (pos+len > count)
		{
			throw new IndexOutOfBoundsException();
		}
		System.arraycopy(buf, pos, bytes, 0, len);
		pos += len;
	}

	final public synchronized void write(int b)
	{
		if (count > pos)
		{
			buf[pos++] = (byte) b;
		}
		else
		{
			super.write(b);
			pos++;
		}
	}

	public synchronized void reset()
	{
		super.reset();
		pos = 0;
	}

	public synchronized byte[] toByteArray()
	{
		count = pos;
		return super.toByteArray();
	}

	public synchronized void writeTo(OutputStream out) throws IOException
	{
		count = pos;
		super.writeTo(out);
	}

    public byte[] getByteArray()
    {
        return buf;
    }
}