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/* Copyright (C) 2003 Vladimir Roubtsov. All rights reserved.
*
* This program and the accompanying materials are made available under
* the terms of the Common Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/cpl-v10.html
*
* $Id: ByteArrayOStream.java,v 1.1.1.1 2004/05/09 16:57:52 vlad_r Exp $
*/
import java.io.IOException;
import java.io.OutputStream;
// ----------------------------------------------------------------------------
/**
* An unsynchronized version of java.io.ByteArrayOutputStream that can expose
* the underlying byte array without a defensive clone and can also be converted
* to a {@link ByteArrayIStream} without intermediate array copies.<p>
*
* All argument validation is disabled in release mode.<p>
*
* NOTE: copy-on-write not supported
*
* @author (C) 2001, Vlad Roubtsov
*/
public
final class ByteArrayOStream extends OutputStream
{
// public: ................................................................
/**
* Callee takes ownership of 'buf'.
*/
public ByteArrayOStream (final int initialCapacity)
{
m_buf = new byte [initialCapacity];
}
public final void write2 (final int b1, final int b2)
{
final int pos = m_pos;
final int capacity = pos + 2;
byte [] mbuf = m_buf;
final int mbuflen = mbuf.length;
if (mbuflen < capacity)
{
final byte [] newbuf = new byte [Math.max (mbuflen << 1, capacity)];
if (pos < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < pos; ++ i) newbuf [i] = mbuf [i];
else
System.arraycopy (mbuf, 0, newbuf, 0, pos);
m_buf = mbuf = newbuf;
}
mbuf [pos] = (byte) b1;
mbuf [pos + 1] = (byte) b2;
m_pos = capacity;
}
public final void write3 (final int b1, final int b2, final int b3)
{
final int pos = m_pos;
final int capacity = pos + 3;
byte [] mbuf = m_buf;
final int mbuflen = mbuf.length;
if (mbuflen < capacity)
{
final byte [] newbuf = new byte [Math.max (mbuflen << 1, capacity)];
if (pos < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < pos; ++ i) newbuf [i] = mbuf [i];
else
System.arraycopy (mbuf, 0, newbuf, 0, pos);
m_buf = mbuf = newbuf;
}
mbuf [pos] = (byte) b1;
mbuf [pos + 1] = (byte) b2;
mbuf [pos + 2] = (byte) b3;
m_pos = capacity;
}
public final void write4 (final int b1, final int b2, final int b3, final int b4)
{
final int pos = m_pos;
final int capacity = pos + 4;
byte [] mbuf = m_buf;
final int mbuflen = mbuf.length;
if (mbuflen < capacity)
{
final byte [] newbuf = new byte [Math.max (mbuflen << 1, capacity)];
if (pos < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < pos; ++ i) newbuf [i] = mbuf [i];
else
System.arraycopy (mbuf, 0, newbuf, 0, pos);
m_buf = mbuf = newbuf;
}
mbuf [pos] = (byte) b1;
mbuf [pos + 1] = (byte) b2;
mbuf [pos + 2] = (byte) b3;
mbuf [pos + 3] = (byte) b4;
m_pos = capacity;
}
public final void writeTo (final OutputStream out)
throws IOException
{
out.write (m_buf, 0, m_pos);
}
// public final void readFully (final InputStream in)
// throws IOException
// {
// while (true)
// {
// int chunk = in.available ();
//
// System.out.println ("available = " + chunk);
//
// // TODO: this case is handled poorly (on EOF)
// if (chunk == 0) chunk = READ_CHUNK_SIZE;
//
// // read at least 'available' bytes: extend the capacity as needed
//
// int free = m_buf.length - m_pos;
//
// final int read;
// if (free > chunk)
// {
// // try reading more than 'chunk' anyway:
// read = in.read (m_buf, m_pos, free);
// }
// else
// {
// // extend the capacity to match 'chunk':
// {
// System.out.println ("reallocation");
// final byte [] newbuf = new byte [m_pos + chunk];
//
// if (m_pos < NATIVE_COPY_THRESHOLD)
// for (int i = 0; i < m_pos; ++ i) newbuf [i] = m_buf [i];
// else
// System.arraycopy (m_buf, 0, newbuf, 0, m_pos);
//
// m_buf = newbuf;
// }
//
// read = in.read (m_buf, m_pos, chunk);
// }
//
// if (read < 0)
// break;
// else
// m_pos += read;
// }
// }
// public final void addCapacity (final int extraCapacity)
// {
// final int pos = m_pos;
// final int capacity = pos + extraCapacity;
// byte [] mbuf = m_buf;
// final int mbuflen = mbuf.length;
//
// if (mbuflen < capacity)
// {
// final byte [] newbuf = new byte [Math.max (mbuflen << 1, capacity)];
//
// if (pos < NATIVE_COPY_THRESHOLD)
// for (int i = 0; i < pos; ++ i) newbuf [i] = mbuf [i];
// else
// System.arraycopy (mbuf, 0, newbuf, 0, pos);
//
// m_buf = newbuf;
// }
// }
public final byte [] getByteArray ()
{
return m_buf;
}
/**
*
* @return [result.length = size()]
*/
public final byte [] copyByteArray ()
{
final int pos = m_pos;
final byte [] result = new byte [pos];
final byte [] mbuf = m_buf;
if (pos < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < pos; ++ i) result [i] = mbuf [i];
else
System.arraycopy (mbuf, 0, result, 0, pos);
return result;
}
public final int size ()
{
return m_pos;
}
public final int capacity ()
{
return m_buf.length;
}
/**
* Does not reduce the current capacity.
*/
public final void reset ()
{
m_pos = 0;
}
// OutputStream:
public final void write (final int b)
{
final int pos = m_pos;
final int capacity = pos + 1;
byte [] mbuf = m_buf;
final int mbuflen = mbuf.length;
if (mbuflen < capacity)
{
final byte [] newbuf = new byte [Math.max (mbuflen << 1, capacity)];
if (pos < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < pos; ++ i) newbuf [i] = mbuf [i];
else
System.arraycopy (mbuf, 0, newbuf, 0, pos);
m_buf = mbuf = newbuf;
}
mbuf [pos] = (byte) b;
m_pos = capacity;
}
public final void write (final byte [] buf, final int offset, final int length)
{
final int pos = m_pos;
final int capacity = pos + length;
byte [] mbuf = m_buf;
final int mbuflen = mbuf.length;
if (mbuflen < capacity)
{
final byte [] newbuf = new byte [Math.max (mbuflen << 1, capacity)];
if (pos < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < pos; ++ i) newbuf [i] = mbuf [i];
else
System.arraycopy (mbuf, 0, newbuf, 0, pos);
m_buf = mbuf = newbuf;
}
if (length < NATIVE_COPY_THRESHOLD)
for (int i = 0; i < length; ++ i) mbuf [pos + i] = buf [offset + i];
else
System.arraycopy (buf, offset, mbuf, pos, length);
m_pos = capacity;
}
/**
* Equivalent to {@link #reset()}.
*/
public final void close ()
{
reset ();
}
// protected: .............................................................
// package: ...............................................................
// private: ...............................................................
private byte [] m_buf;
private int m_pos;
// private static final int READ_CHUNK_SIZE = 16 * 1024;
private static final int NATIVE_COPY_THRESHOLD = 9;
} // end of class
// ----------------------------------------------------------------------------
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