Class PipedWriter

java.lang.Object

java.io.Writer

java.io.PipedWriter

All Implemented Interfaces:: Closeable, Flushable, Appendable, AutoCloseable

public class PipedWriter extends Writer

Piped character-output streams.

Since:: 1.1

Field Summary

Fields declared in class Writer

lock

Modifier and Type	Field	Description
`protected Object`	`lock`	The object used to synchronize operations on this stream.

Constructor Summary

Constructor	Description
`PipedWriter()`	Creates a piped writer that is not yet connected to a piped reader.
`PipedWriter(PipedReader snk)`	Creates a piped writer connected to the specified piped reader.

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(PipedReader snk)`	Connects this piped writer to a receiver.
`void`	`flush()`	Flushes this output stream and forces any buffered output characters to be written out.
`void`	`write(char[] cbuf, int off, int len)`	Writes `len` characters from the specified character array starting at offset `off` to this piped output stream.
`void`	`write(int c)`	Writes the specified `char` to the piped output stream.

Methods declared in class Writer

append, append, append, nullWriter, write, write, write

Modifier and Type	Method	Description
`Writer`	`append(char c)`	Appends the specified character to this writer.
`Writer`	`append(CharSequence csq)`	Appends the specified character sequence to this writer.
`Writer`	`append(CharSequence csq, int start, int end)`	Appends a subsequence of the specified character sequence to this writer.
`static Writer`	`nullWriter()`	Returns a new `Writer` which discards all characters.
`void`	`write(char[] cbuf)`	Writes an array of characters.
`void`	`write(String str)`	Writes a string.
`void`	`write(String str, int off, int len)`	Writes a portion of a string.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

PipedWriter

public PipedWriter(PipedReader snk) throws IOException

Creates a piped writer connected to the specified piped reader. Data characters written to this stream will then be available as input from snk.

Parameters:: snk - The piped reader to connect to.
Throws:: IOException - if an I/O error occurs.

PipedWriter

public PipedWriter()

Creates a piped writer that is not yet connected to a piped reader. It must be connected to a piped reader, either by the receiver or the sender, before being used.

See Also:

Method Details

connect

public void connect(PipedReader snk) throws IOException

Connects this piped writer to a receiver. If this object is already connected to some other piped reader, an IOException is thrown.

If snk is an unconnected piped reader and src is an unconnected piped writer, 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 reader to connect to.
Throws:: IOException - if an I/O error occurs.

write

public void write(int c) throws IOException

Writes the specified char to the piped output stream. If a thread was reading data characters from the connected piped input stream, but the thread is no longer alive, then an IOException is thrown.

Implements the write method of Writer.

Overrides:: write in class Writer
Parameters:: c - the char to be written.
Throws:: IOException - if the pipe is broken, unconnected, closed or an I/O error occurs.

write

public void write(char[] cbuf, int off, int len) throws IOException

Writes len characters from the specified character array starting at offset off to this piped output stream. This method blocks until all the characters are written to the output stream. If a thread was reading data characters from the connected piped input stream, but the thread is no longer alive, then an IOException is thrown.

Specified by:: write in class Writer
Parameters:: cbuf - the data.; off - the start offset in the data.; len - the number of characters to write.
Throws:: IndexOutOfBoundsException - If off is negative, or len is negative, or off + len is negative or greater than the length of the given array; IOException - if the pipe is broken, unconnected, closed or an I/O error occurs.

flush

public void flush() throws IOException

Flushes this output stream and forces any buffered output characters to be written out. This will notify any readers that characters are waiting in the pipe.

Specified by:: flush in interface Flushable
Specified by:: flush in class Writer
Throws:: IOException - if the pipe is closed, or 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 characters.

Specified by:: close in interface AutoCloseable
Specified by:: close in interface Closeable
Specified by:: close in class Writer
Throws:: IOException - if an I/O error occurs.

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