PipedReader

public class PipedReader extends Reader

Piped character-input streams.

Inherited Field Summary

From class java.io.Reader

protected Object

lock

The object used to synchronize operations on this stream.

Public Constructor Summary

	PipedReader(PipedWriter src) Creates a PipedReader so that it is connected to the piped writer src.
	PipedReader(PipedWriter src, int pipeSize) Creates a PipedReader so that it is connected to the piped writer src and uses the specified pipe size for the pipe's buffer.
	PipedReader() Creates a PipedReader so that it is not yet {@linkplain #connect(java.io.PipedWriter) connected}.
	PipedReader(int pipeSize) Creates a PipedReader so that it is not yet connected and uses the specified pipe size for the pipe's buffer.

Public Method Summary

void	close() Closes this piped stream and releases any system resources associated with the stream.
void	connect(PipedWriter src) Causes this piped reader to be connected to the piped writer src.
synchronized int	read() Reads the next character of data from this piped stream.
synchronized int	read(char[] cbuf, int off, int len) Reads up to len characters of data from this piped stream into an array of characters.
synchronized boolean	ready() Tell whether this stream is ready to be read.

Inherited Method Summary

From class java.io.Reader

abstract void	close() Closes the stream and releases any system resources associated with it.
void	mark(int readAheadLimit) Marks the present position in the stream.
boolean	markSupported() Tells whether this stream supports the mark() operation.
int	read() Reads a single character.
abstract int	read(char[] cbuf, int off, int len) Reads characters into a portion of an array.
int	read(char[] cbuf) Reads characters into an array.
int	read(CharBuffer target) Attempts to read characters into the specified character buffer.
boolean	ready() Tells whether this stream is ready to be read.
void	reset() Resets the stream.
long	skip(long n) Skips characters.

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

From interface java.lang.Readable

abstract int

read(CharBuffer cb) Attempts to read characters into the specified character buffer.

From interface java.io.Closeable

abstract void

close() Closes this stream and releases any system resources associated with it.

From interface java.lang.AutoCloseable

abstract void

close() Closes this resource, relinquishing any underlying resources.

Public Constructors

public PipedReader (PipedWriter src)

Creates a PipedReader so that it is connected to the piped writer src. Data written to src will then be available as input from this stream.

Parameters

src	the stream to connect to.

Throws

IOException	if an I/O error occurs.

public PipedReader (PipedWriter src, int pipeSize)

Creates a PipedReader so that it is connected to the piped writer src and uses the specified pipe size for the pipe's buffer. Data written to src will then be available as input from this stream.

Parameters

src	the stream to connect to.
pipeSize	the size of the pipe's buffer.

Throws

IOException	if an I/O error occurs.
IllegalArgumentException	if pipeSize <= 0.

public PipedReader ()

Creates a PipedReader so that it is not yet {@linkplain #connect(java.io.PipedWriter) connected}. It must be {@linkplain java.io.PipedWriter#connect( java.io.PipedReader) connected} to a PipedWriter before being used.

public PipedReader (int pipeSize)

Creates a PipedReader so that it is not yet connected and uses the specified pipe size for the pipe's buffer. It must be {@linkplain java.io.PipedWriter#connect( java.io.PipedReader) connected} to a PipedWriter before being used.

Parameters

pipeSize	the size of the pipe's buffer.

Throws

IllegalArgumentException	if pipeSize <= 0.

Public Methods

public void close ()

Closes this piped stream and releases any system resources associated with the stream.

Throws

IOException	if an I/O error occurs.

public void connect (PipedWriter src)

Causes this piped reader to be connected to the piped writer src. If this object is already connected to some other piped writer, an IOException is thrown.

If src is an unconnected piped writer and snk is an unconnected piped reader, they may be connected by either the call:

snk.connect(src) 

or the call:

src.connect(snk) 

The two calls have the same effect.

Parameters

src	The piped writer to connect to.

Throws

IOException	if an I/O error occurs.

public synchronized int read ()

Reads the next character of data from this piped stream. If no character is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

Returns

• the next character of data, or -1 if the end of the stream is reached.

Throws

IOException	if the pipe is broken, unconnected, closed, or an I/O error occurs.

public synchronized int read (char[] cbuf, int off, int len)

Reads up to len characters of data from this piped stream into an array of characters. Less than len characters will be read if the end of the data stream is reached or if len exceeds the pipe's buffer size. This method blocks until at least one character of input is available.

Parameters

cbuf	the buffer into which the data is read.
off	the start offset of the data.
len	the maximum number of characters read.

Returns

• the total number of characters read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Throws

IOException	if the pipe is broken, unconnected, closed, or an I/O error occurs.

public synchronized boolean ready ()

Tell whether this stream is ready to be read. A piped character stream is ready if the circular buffer is not empty.

Returns

• True if the next read() is guaranteed not to block for input, false otherwise. Note that returning false does not guarantee that the next read will block.

Throws

IOException	if the pipe is broken, unconnected, or closed.