using System;
using System.IO;
using System.Runtime.CompilerServices;
namespace Tamir.Streams{
/*
* @(#)PipedOutputStream.java 1.26 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
/**
* A piped output stream can be connected to a piped input stream
* to create a communications pipe. The piped output stream is the
* sending end of the pipe. Typically, data is written to a
* <code>PipedOutputStream</code> object by one thread and data is
* read from the connected <code>PipedInputStream</code> by some
* other thread. Attempting to use both objects from a single thread
* is not recommended as it may deadlock the thread.
*
* @author James Gosling
* @version 1.26, 12/19/03
* @see java.io.PipedInputStream
* @since JDK1.0
*/
public class PipedOutputStream : Tamir.SharpSsh.java.io.OutputStream
{
/* REMIND: identification of the read and write sides needs to be
more sophisticated. Either using thread groups (but what about
pipes within a thread?) or using finalization (but it may be a
long time until the next GC). */
private PipedInputStream sink;
/**
* Creates a piped output stream connected to the specified piped
* input stream. Data bytes written to this stream will then be
* available as input from <code>snk</code>.
*
* @param snk The piped input stream to connect to.
* @exception IOException if an I/O error occurs.
*/
public PipedOutputStream(PipedInputStream snk)
{
connect(snk);
}
/**
* Creates a piped output stream that is not yet connected to a
* piped input stream. It must be connected to a piped input stream,
* either by the receiver or the sender, before being used.
*
* @see java.io.PipedInputStream#connect(java.io.PipedOutputStream)
* @see java.io.PipedOutputStream#connect(java.io.PipedInputStream)
*/
public PipedOutputStream()
{
}
/**
* Connects this piped output stream to a receiver. If this object
* is already connected to some other piped input stream, an
* <code>IOException</code> is thrown.
* <p>
* If <code>snk</code> is an unconnected piped input stream and
* <code>src</code> is an unconnected piped output stream, they may
* be connected by either the call:
* <blockquote><pre>
* src.connect(snk)</pre></blockquote>
* or the call:
* <blockquote><pre>
* snk.connect(src)</pre></blockquote>
* The two calls have the same effect.
*
* @param snk the piped input stream to connect to.
* @exception IOException if an I/O error occurs.
*/
[MethodImpl(MethodImplOptions.Synchronized)]
public virtual void connect(PipedInputStream snk)
{
if (snk == null)
{
throw new NullReferenceException();
}
else if (sink != null || snk.connected)
{
throw new IOException("Already connected");
}
sink = snk;
snk.m_in = -1;
snk.m_out = 0;
snk.connected = true;
int t=0;
}
/**
* Writes the specified <code>byte</code> to the piped output stream.
* If a thread was reading data bytes from the connected piped input
* stream, but the thread is no longer alive, then an
* <code>IOException</code> is thrown.
* <p>
* Implements the <code>write</code> method of <code>OutputStream</code>.
*
* @param b the <code>byte</code> to be written.
* @exception IOException if an I/O error occurs.
*/
public virtual void write(int b)
{
if (sink == null)
{
throw new IOException("Pipe not connected");
}
sink.receive(b);
}
/**
* Writes <code>len</code> bytes from the specified byte array
* starting at offset <code>off</code> to this piped output stream.
* If a thread was reading data bytes from the connected piped input
* stream, but the thread is no longer alive, then an
* <code>IOException</code> is thrown.
*
* @param b the data.
* @param off the start offset in the data.
* @param len the number of bytes to write.
* @exception IOException if an I/O error occurs.
*/
public override void write(byte[] b, int off, int len)
{
if (sink == null)
{
throw new IOException("Pipe not connected");
}
else if (b == null)
{
throw new NullReferenceException();
}
else if ((off < 0) || (off > b.Length) || (len < 0) ||
((off + len) > b.Length) || ((off + len) < 0))
{
throw new IndexOutOfRangeException();
}
else if (len == 0)
{
return;
}
sink.receive(b, off, len);
}
public virtual void write(byte[] b)
{
write(b, 0, b.Length);
}
/**
* Flushes this output stream and forces any buffered output bytes
* to be written out.
* This will notify any readers that bytes are waiting in the pipe.
*
* @exception IOException if an I/O error occurs.
*/
[MethodImpl(MethodImplOptions.Synchronized)]
public override void flush()
{
if (sink != null)
{
lock (sink)
{
//sink.notifyAll();
System.Threading.Monitor.PulseAll(sink);
}
}
}
/**
* Closes this piped output stream and releases any system resources
* associated with this stream. This stream may no longer be used for
* writing bytes.
*
* @exception IOException if an I/O error occurs.
*/
public override void close()
{
if (sink != null)
{
sink.receivedLast();
}
}
///////////////////////////////////////
public override int Read(byte[] buffer, int offset, int count)
{
return 0;
}
public override int ReadByte()
{
return 0;
}
public override void WriteByte(byte value)
{
this.write(value);
}
public override void Write(byte[] buffer, int offset, int count)
{
this.write(buffer, offset, count);
}
public virtual void Write(byte[] buffer)
{
this.Write(buffer, 0, buffer.Length);
}
public override void Close()
{
base.Close ();
this.close();
}
public override bool CanRead
{
get
{
return false;
}
}
public override bool CanWrite
{
get
{
return true;
}
}
public override bool CanSeek
{
get
{
return false;
}
}
public override void Flush()
{
this.flush();
}
public override long Length
{
get
{
return sink.Length;
}
}
public override long Position
{
get
{
return sink.m_in;
}
set
{
throw new IOException("Setting the position of this stream is not supported");
}
}
public override void SetLength(long value)
{
throw new IOException("Setting the length of this stream is not supported");
}
public override long Seek(long offset, SeekOrigin origin)
{
return 0;
}
}
}
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