fastbytearrayoutputstream.java

struts 2 核心包 的源码 有错误是难免的

// Decompiled by Jad v1.5.8e2. Copyright 2001 Pavel Kouznetsov.
// Jad home page: http://kpdus.tripod.com/jad.html
// Decompiler options: packimports(3) fieldsfirst ansi space 
// Source File Name:   FastByteArrayOutputStream.java

package org.apache.struts2.util;

import java.io.*;
import java.util.Iterator;
import java.util.LinkedList;

public class FastByteArrayOutputStream extends OutputStream
{

	private static final int DEFAULT_BLOCK_SIZE = 8192;
	private LinkedList buffers;
	private byte buffer[];
	private boolean closed;
	private int blockSize;
	private int index;
	private int size;

	public FastByteArrayOutputStream()
	{
		this(8192);
	}

	public FastByteArrayOutputStream(int aSize)
	{
		blockSize = aSize;
		buffer = new byte[blockSize];
	}

	public int getSize()
	{
		return size + index;
	}

	public void close()
	{
		closed = true;
	}

	public byte[] toByteArray()
	{
		byte data[] = new byte[getSize()];
		int pos = 0;
		if (buffers != null)
		{
			for (Iterator iter = buffers.iterator(); iter.hasNext();)
			{
				byte bytes[] = (byte[])(byte[])iter.next();
				System.arraycopy(bytes, 0, data, pos, blockSize);
				pos += blockSize;
			}

		}
		System.arraycopy(buffer, 0, data, pos, index);
		return data;
	}

	public String toString()
	{
		return new String(toByteArray());
	}

	public void write(int datum)
		throws IOException
	{
		if (closed)
			throw new IOException("Stream closed");
		if (index == blockSize)
			addBuffer();
		buffer[index++] = (byte)datum;
	}

	public void write(byte data[], int offset, int length)
		throws IOException
	{
		if (data == null)
			throw new NullPointerException();
		if (offset < 0 || offset + length > data.length || length < 0)
			throw new IndexOutOfBoundsException();
		if (closed)
			throw new IOException("Stream closed");
		if (index + length > blockSize)
		{
			do
			{
				if (index == blockSize)
					addBuffer();
				int copyLength = blockSize - index;
				if (length < copyLength)
					copyLength = length;
				System.arraycopy(data, offset, buffer, index, copyLength);
				offset += copyLength;
				index += copyLength;
				length -= copyLength;
			} while (length > 0);
		} else
		{
			System.arraycopy(data, offset, buffer, index, length);
			index += length;
		}
	}

	public void writeTo(OutputStream out)
		throws IOException
	{
		if (buffers != null)
		{
			byte bytes[];
			for (Iterator iter = buffers.iterator(); iter.hasNext(); out.write(bytes, 0, blockSize))
				bytes = (byte[])(byte[])iter.next();

		}
		out.write(buffer, 0, index);
	}

	public void writeTo(RandomAccessFile out)
		throws IOException
	{
		if (buffers != null)
		{
			byte bytes[];
			for (Iterator iter = buffers.iterator(); iter.hasNext(); out.write(bytes, 0, blockSize))
				bytes = (byte[])(byte[])iter.next();

		}
		out.write(buffer, 0, index);
	}

	public void writeTo(Writer out, String encoding)
		throws IOException
	{
		if (buffers != null)
		{
			for (Iterator iter = buffers.iterator(); iter.hasNext();)
			{
				byte bytes[] = (byte[])(byte[])iter.next();
				if (encoding != null)
					out.write(new String(bytes, encoding));
				else
					out.write(new String(bytes));
			}

		}
		if (encoding != null)
			out.write(new String(buffer, 0, index, encoding));
		else
			out.write(new String(buffer, 0, index));
	}

	protected void addBuffer()
	{
		if (buffers == null)
			buffers = new LinkedList();
		buffers.addLast(buffer);
		buffer = new byte[blockSize];
		size += index;
		index = 0;
	}
}