Class PipedReader
- java.lang.Object
-
- java.io.Reader
-
- java.io.PipedReader
- All Implemented Interfaces:
-
Closeable
,AutoCloseable
,Readable
public class PipedReader extends Reader
Piped character-input streams.
- Since:
- 1.1
Field Summary
Fields declared in class java.io.Reader
lock
Constructor Summary
Constructor | Description |
---|---|
PipedReader() | Creates a |
PipedReader(int pipeSize) | Creates a |
PipedReader(PipedWriter src) | Creates a |
PipedReader(PipedWriter src,
int pipeSize) | Creates a |
Method Summary
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 |
int | read() | Reads the next character of data from this piped stream. |
int | read(char[] cbuf,
int off,
int len) | Reads up to |
boolean | ready() | Tell whether this stream is ready to be read. |
Methods declared in class java.io.Reader
mark, markSupported, nullReader, read, read, reset, skip, transferTo
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
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
- ifpipeSize <= 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
- ifpipeSize <= 0
. - Since:
- 1.6
Method Detail
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:
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() 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 classReader
- 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) throws IOException
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.
- Specified by:
-
read
in classReader
- 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 isbroken
,unconnected
, closed, or an I/O error occurs. -
IndexOutOfBoundsException
- If 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 classReader
- 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() throws IOException
Closes this piped stream and releases any system resources associated with the stream.
- Specified by:
-
close
in interfaceAutoCloseable
- Specified by:
-
close
in interfaceCloseable
- Specified by:
-
close
in classReader
- Throws:
-
IOException
- if an I/O error occurs.