java.io
Class PipedReader
java.lang.Object
|
+--java.io.Reader
|
+--java.io.PipedReader
- public class PipedReader
- extends Reader
Untamed:
Field Summary
(package private) char[]
buffer
The circular buffer into which incoming data is placed.
(package private) int
in
The index of the position in the circular buffer at which the
next character of data will be stored when received from the connected
piped writer.
(package private) int
out
The index of the position in the circular buffer at which the next
character of data will be read by this piped reader.
(package private) static int
PIPE_SIZE
The size of the pipe's circular input buffer.
Fields inherited from class java.io.Reader
Constructor Summary
PipedReader()
Enabled: Creates a
PipedReader so
that it is not yet connected.
Method Summary
void
close()
Enabled: Closes this piped stream and releases any system resources
associated with the stream.
void
connect(PipedWriter src)
Enabled: Causes this piped reader to be connected
to the piped writer
src.
int
read()
Enabled: Reads the next character of data from this piped stream.
int
read(char[] cbuf,
int off,
int len)
Enabled: Reads up to
len characters of data from this piped
stream into an array of characters.
boolean
ready()
Enabled: Tell whether this stream is ready to be read.
(package private) void
receive(char[] c,
int off,
int len)
Receives data into an array of characters.
(package private) void
receive(int c)
Receives a char of data.
(package private) void
receivedLast()
Notifies all waiting threads that the last character of data has been
received.
Methods inherited from class java.io.Reader
getText, getTwine, iterate, iterate, mark, markSupported, read, readChar, readString, reset, skip
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Field Detail
closedByWriter
boolean closedByWriter
closedByReader
boolean closedByReader
connected
boolean connected
readSide
Thread readSide
writeSide
Thread writeSide
PIPE_SIZE
static final int PIPE_SIZE
- The size of the pipe's circular input buffer.
buffer
char[] buffer
- The circular buffer into which incoming data is placed.
in
int in
- The index of the position in the circular buffer at which the
next character of data will be stored when received from the connected
piped writer.
in<0 implies the buffer is empty,
in==out implies the buffer is full
out
int out
- The index of the position in the circular buffer at which the next
character of data will be read by this piped reader.
Constructor Detail
PipedReader
public PipedReader(PipedWriter src)
throws IOException
- Enabled: 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.
PipedReader
public PipedReader()
- Enabled: Creates a
PipedReader so
that it is not yet connected. It must be
connected to a PipedWriter
before being used.
- See Also:
java.io.PipedReader#connect(java.io.PipedWriter),
java.io.PipedWriter#connect(java.io.PipedReader)
Method Detail
connect
public void connect(PipedWriter src)
throws IOException
- Enabled: 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.
IOException
receive
void receive(int c)
throws IOException
- Receives a char of data. This method will block if no input is
available.
IOException
receive
void receive(char[] c,
int off,
int len)
throws IOException
- Receives data into an array of characters. This method will
block until some input is available.
IOException
receivedLast
void receivedLast()
- Notifies all waiting threads that the last character of data has been
received.
-
read
public int read()
throws IOException
- Enabled: 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.
If a thread was providing data characters
to the connected piped writer, but
the thread is no longer alive, then an
IOException is thrown.
- Overrides:
read in class Reader
- Returns:
- the next character of data, or
-1 if the end of the
stream is reached.
IOException
read
public int read(char[] cbuf,
int off,
int len)
throws IOException
- Enabled: 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. This method
blocks until at least one character of input is available.
If a thread was providing data characters to the connected piped output,
but the thread is no longer alive, then an IOException
is thrown.
- Specified by:
read in class Reader
- 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.
IOException
ready
public boolean ready()
throws IOException
- Enabled: 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.
IOException
close
public void close()
throws IOException
- Enabled: Closes this piped stream and releases any system resources
associated with the stream.
- Specified by:
close in class Reader
IOException