Class PipedReader
java.lang.Object
java.io.Reader
java.io.PipedReader
- All Implemented Interfaces:
Closeable
,AutoCloseable
,Readable
Piped character-input streams.
- Since:
- 1.1
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Field Summary
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Constructor Summary
ConstructorDescriptionCreates aPipedReader
so that it is not yet connected.PipedReader
(int pipeSize) Creates aPipedReader
so that it is not yetconnected
and uses the specified pipe size for the pipe's buffer.PipedReader
(PipedWriter src) Creates aPipedReader
so that it is connected to the piped writersrc
.PipedReader
(PipedWriter src, int pipeSize) Creates aPipedReader
so that it is connected to the piped writersrc
and uses the specified pipe size for the pipe's buffer. -
Method Summary
Modifier and TypeMethodDescriptionvoid
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 writersrc
.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, read, read, reset, skip, transferTo
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Constructor Details
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PipedReader
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
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
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PipedReader
-
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 be connected to aPipedWriter
before being used.- Parameters:
pipeSize
- the size of the pipe's buffer.- Throws:
IllegalArgumentException
- ifpipeSize <= 0
.- Since:
- 1.6
-
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Method Details
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connect
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.If
src
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
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.
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read
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 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 than
len
characters will be read iflen
exceeds the pipe's buffer size.- Specified by:
read
in classReader
- Parameters:
cbuf
- Destination bufferoff
- Offset at which to start storing characterslen
- 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.
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ready
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.
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close
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.
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