Class PipedReader

java.lang.Object
java.io.Reader
java.io.PipedReader
All Implemented Interfaces:
Closeable,AutoCloseable,Readable

public classPipedReaderextendsReader
Piped character-input streams.
Since:
1.1
  • Constructor Details

    • PipedReader

      public PipedReader(PipedWriter src) throwsIOException
      Creates aPipedReader so that it is connected to the piped writersrc. Data written tosrc 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) throwsIOException
      Creates aPipedReader so that it is connected to the piped writersrc and uses the specified pipe size for the pipe's buffer. Data written tosrc 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 - ifpipeSize <= 0.
      Since:
      1.6
    • PipedReader

      public PipedReader()
      Creates aPipedReader so that it is not yetconnected. It must beconnected to aPipedWriter before being used.
    • PipedReader

      public PipedReader(int pipeSize)
      Creates aPipedReader so that it is not yetconnected and uses the specified pipe size for the pipe's buffer. It must beconnected to aPipedWriter before being used.
      Parameters:
      pipeSize - the size of the pipe's buffer.
      Throws:
      IllegalArgumentException - ifpipeSize <= 0.
      Since:
      1.6
  • Method Details

    • connect

      public void connect(PipedWriter src) throwsIOException
      Causes this piped reader to be connected to the piped writersrc. If this object is already connected to some other piped writer, anIOException is thrown.

      Ifsrc is an unconnected piped writer andsnk 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.
    • read

      public int read() throwsIOException
      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 isbroken,unconnected, closed, or an I/O error occurs.
    • read

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

      Iflen is zero, then no characters are read and0 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 intocbuf.

      Fewer thanlen characters will be read iflen 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 - Ifoff is negative, orlen is negative, orlen is greater thancbuf.length - off
      IOException - if the pipe isbroken,unconnected, closed, or an I/O error occurs.
    • ready

      public boolean ready() throwsIOException
      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 isbroken,unconnected, or closed.
    • close

      public void close() throwsIOException
      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.