1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Constructor Details
   1. PipedReader(PipedWriter)
   2. PipedReader(PipedWriter, int)
   3. PipedReader()
   4. PipedReader(int)
6. Method Details
   1. connect(PipedWriter)
   2. read()
   3. read(char[], int, int)
   4. ready()
   5. close()

All Implemented Interfaces:

Closeable, AutoCloseable, Readable

• Field Summary

  Fields declared in class java.io.Reader

  lock

• Constructor Summary

  Constructors
  Constructor

  Description

  PipedReader()

  Creates a PipedReader so that it is not yet 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.

  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.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  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.

  int

  read()

  Reads the next character of data from this piped stream.

  int

  read(char[] cbuf, int off, int len)

  Reads characters into a portion of an array.

  boolean

  ready()

  Tell whether this stream is ready to be read.

  Methods declared in class java.io.Reader

  mark, markSupported, nullReader, of, read, read, reset, skip, transferTo

  Methods declared in class java.lang.Object

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

• Constructor Details

  • PipedReader

    public PipedReader(PipedWriter src) throws IOException

    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.

  • PipedReader

    public PipedReader(PipedWriter src, int pipeSize) throws IOException

    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.

    Since:

    1.6

  • PipedReader

    public PipedReader()

    Creates a PipedReader so that it is not yet connected. It must be connected to a PipedWriter before being used.

  • PipedReader

    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 connected to a PipedWriter before being used.

    Parameters:

    pipeSize - the size of the pipe's buffer.

    Throws:

    IllegalArgumentException - if pipeSize <= 0.

    Since:

    1.6

• Method Details

  • connect

    public void connect(PipedWriter src) throws IOException

    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:

    Copy [Copy snippet]

        snk.connect(src)
    

    or the call:

    Copy [Copy snippet]

        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.

  • read

    public int read() throws IOException

    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.

    Overrides:

    read in class Reader

    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.

  • read

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

    Reads characters into a portion of an array. This method will block until some input is available, an I/O error occurs, or the end of the stream is reached.

    If len is zero, then no characters are read and 0 is returned; otherwise, there is an attempt to read at least one character. If no character is available because the stream is at its end, the value -1 is returned; otherwise, at least one character is read and stored into cbuf.

    Fewer than len characters will be read if len exceeds the pipe's buffer size.

    Specified by:

    read in class Reader

    Parameters:

    cbuf - Destination buffer

    off - Offset at which to start storing characters

    len - Maximum number of characters to read

    Returns:

    The number of characters read, or -1 if the end of the stream has been reached

    Throws:

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

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

  • ready

    public boolean ready() throws IOException

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

    Overrides:

    ready in class Reader

    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.

  • close

    public void close() throws IOException

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

    Specified by:

    close in interface AutoCloseable

    Specified by:

    close in interface Closeable

    Specified by:

    close in class Reader

    Throws:

    IOException - if an I/O error occurs.

Report a bug or suggest an enhancement
For further API reference and developer documentation see the Java SE Documentation, which contains more detailed, developer-targeted descriptions with conceptual overviews, definitions of terms, workarounds, and working code examples. Other versions.
Java is a trademark or registered trademark of Oracle and/or its affiliates in the US and other countries.
Copyright © 1993, 2025, Oracle and/or its affiliates, 500 Oracle Parkway, Redwood Shores, CA 94065 USA.
All rights reserved. Use is subject to license terms and the documentation redistribution policy.