java.io
Class PipedOutputStream

java.lang.Object
  java.io.OutputStream
      java.io.PipedOutputStream

public class PipedOutputStream

extends OutputStream

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 PipedOutputStream object by one thread and data is read from the connected PipedInputStream by some other thread. Attempting to use both objects from a single thread is not recommended as it may deadlock the thread.

Since:

JDK1.0

Author:

James Gosling

See Also:

PipedInputStream

Field Summary

private PipedInputStream

sink

Constructor Summary

PipedOutputStream()
Creates a piped output stream that is not yet connected to a piped input stream.

PipedOutputStream(PipedInputStream snk)
Creates a piped output stream connected to the specified piped input stream.

Method Summary

void	close() Closes this piped output stream and releases any system resources associated with this stream.
void	connect(PipedInputStream snk) Connects this piped output stream to a receiver.
void	flush() Flushes this output stream and forces any buffered output bytes to be written out.
void	write(byte[] b, int off, int len) Writes len bytes from the specified byte array starting at offset off to this piped output stream.
void	write(int b) Writes the specified byte to the piped output stream.

Methods inherited from class java.io.OutputStream

write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

sink

private PipedInputStream sink

Constructor Detail

PipedOutputStream

public PipedOutputStream(PipedInputStream snk)
                  throws IOException

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 snk.

Parameters:

snk - The piped input stream to connect to.

Throws:

IOException - if an I/O error occurs.

PipedOutputStream

public PipedOutputStream()

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 Also:

PipedInputStream.connect(java.io.PipedOutputStream), connect(java.io.PipedInputStream)

Method Detail

connect

public void connect(PipedInputStream snk)
             throws IOException

Connects this piped output stream to a receiver. If this object is already connected to some other piped input stream, an IOException is thrown.

If snk is an unconnected piped input stream and src is an unconnected piped output stream, they may be connected by either the call:

 src.connect(snk)

or the call:

 snk.connect(src)

The two calls have the same effect.

Parameters:

snk - the piped input stream to connect to.

Throws:

IOException - if an I/O error occurs.

write

public void write(int b)
           throws IOException

Writes the specified byte 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 IOException is thrown.

Implements the write method of OutputStream.

Specified by:

write in class OutputStream

Parameters:

b - the byte to be written.

Throws:

IOException - if an I/O error occurs.

write

public void write(byte[] b,
                  int off,
                  int len)
           throws IOException

Writes len bytes from the specified byte array starting at offset off 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 IOException is thrown.

Overrides:

write in class OutputStream

Parameters:

b - the data.

off - the start offset in the data.

len - the number of bytes to write.

Throws:

IOException - if an I/O error occurs.

flush

public void flush()
           throws IOException

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.

Overrides:

flush in class OutputStream

Throws:

IOException - if an I/O error occurs.

close

public void close()
           throws IOException

Closes this piped output stream and releases any system resources associated with this stream. This stream may no longer be used for writing bytes.

Overrides:

close in class OutputStream

Throws:

IOException - if an I/O error occurs.