Class PipedOutputStream

java.lang.Object

java.io.OutputStream

java.io.PipedOutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

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. The pipe is said to be broken if a thread that was reading data bytes from the connected piped input stream is no longer alive.

Since:

1.0

See Also:

• PipedInputStream

Constructor Summary

Constructors

Constructor	Description
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

Modifier and Type	Method	Description
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 declared in class OutputStream

nullOutputStream, write

Modifier and Type	Method	Description
static OutputStream	nullOutputStream()	Returns a new OutputStream which discards all bytes.
void	write(byte[] b)	Writes b.length bytes from the specified byte array to this output stream.

Methods declared in class Object

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

Modifier and Type	Method	Description
protected Object	clone()	Answers a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
boolean	equals(Object o)	Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
protected void	finalize()	Deprecated, for removal: This API element is subject to removal in a future version. May cause performance issues, deadlocks and hangs.
final Class<? extends Object>	getClass()	Answers the unique instance of java.lang.Class which represents the class of the receiver.
int	hashCode()	Answers an integer hash code for the receiver.
final void	notify()	Causes one thread which is waiting on the receiver to be made ready to run.
final void	notifyAll()	Causes all threads which are waiting on the receiver to be made ready to run.
String	toString()	Answers a string containing a concise, human-readable description of the receiver.
final void	wait()	Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
final void	wait(long time)	Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
final void	wait(long time, int frac)	Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

Constructor Details

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 Details

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.

Implements the write method of OutputStream.

Specified by:

write in class OutputStream

Parameters:

b - the byte to be written.

Throws:

IOException - if the pipe is broken, unconnected, closed, or 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 len is not zero, this method blocks until all the bytes are written to the output stream.

Overrides:

write in class OutputStream

Parameters:

b - the data.

off - the start offset in the data.

len - the number of bytes to write.

Throws:

IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off

IOException - if the pipe is broken, unconnected, closed and len is greater than zero, or 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.

Specified by:

flush in interface Flushable

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.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException - if an I/O error occurs.