org.apache.commons.exec

Class PumpStreamHandler

java.lang.Object

org.apache.commons.exec.PumpStreamHandler

All Implemented Interfaces:

ExecuteStreamHandler

public class PumpStreamHandler
extends java.lang.Object
implements ExecuteStreamHandler

Copies standard output and error of sub-processes to standard output and error of the parent process. If output or error stream are set to null, any feedback from that stream will be lost.

Version:

$Id: PumpStreamHandler.java 1557263 2014-01-10 21:18:09Z ggregory $

Field Summary

Fields

Modifier and Type	Field and Description
private java.io.IOException	caught the last exception being caught
private java.io.OutputStream	err
private java.lang.Thread	errorThread
private java.io.InputStream	input
private InputStreamPumper	inputStreamPumper
private java.lang.Thread	inputThread
private java.io.OutputStream	out
private java.lang.Thread	outputThread
private static long	STOP_TIMEOUT_ADDITION
private long	stopTimeout the timeout in ms the implementation waits when stopping the pumper threads

Constructor Summary

Constructors

Constructor and Description
PumpStreamHandler() Construct a new PumpStreamHandler.
PumpStreamHandler(java.io.OutputStream outAndErr) Construct a new PumpStreamHandler.
PumpStreamHandler(java.io.OutputStream out, java.io.OutputStream err) Construct a new PumpStreamHandler.
PumpStreamHandler(java.io.OutputStream out, java.io.OutputStream err, java.io.InputStream input) Construct a new PumpStreamHandler.

Method Summary

Modifier and Type	Method and Description
protected void	createProcessErrorPump(java.io.InputStream is, java.io.OutputStream os) Create the pump to handle error output.
protected void	createProcessOutputPump(java.io.InputStream is, java.io.OutputStream os) Create the pump to handle process output.
protected java.lang.Thread	createPump(java.io.InputStream is, java.io.OutputStream os) Creates a stream pumper to copy the given input stream to the given output stream.
protected java.lang.Thread	createPump(java.io.InputStream is, java.io.OutputStream os, boolean closeWhenExhausted) Creates a stream pumper to copy the given input stream to the given output stream.
private java.lang.Thread	createSystemInPump(java.io.InputStream is, java.io.OutputStream os) Creates a stream pumper to copy the given input stream to the given output stream.
protected java.io.OutputStream	getErr() Get the error stream.
protected java.io.OutputStream	getOut() Get the output stream.
void	setProcessErrorStream(java.io.InputStream is) Set the InputStream from which to read the standard error of the process.
void	setProcessInputStream(java.io.OutputStream os) Set the OutputStream by means of which input can be sent to the process.
void	setProcessOutputStream(java.io.InputStream is) Set the InputStream from which to read the standard output of the process.
void	setStopTimeout(long timeout) Set maximum time to wait until output streams are exchausted when stop() was called.
void	start() Start the Threads.
void	stop() Stop pumping the streams.
protected void	stopThread(java.lang.Thread thread, long timeout) Stopping a pumper thread.

Methods inherited from class java.lang.Object

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

Field Detail

STOP_TIMEOUT_ADDITION

private static final long STOP_TIMEOUT_ADDITION

See Also:

Constant Field Values

outputThread

private java.lang.Thread outputThread

errorThread

private java.lang.Thread errorThread

inputThread

private java.lang.Thread inputThread

out

private final java.io.OutputStream out

err

private final java.io.OutputStream err

input

private final java.io.InputStream input

inputStreamPumper

private InputStreamPumper inputStreamPumper

stopTimeout

private long stopTimeout

the timeout in ms the implementation waits when stopping the pumper threads

caught

private java.io.IOException caught

the last exception being caught

Constructor Detail

PumpStreamHandler

public PumpStreamHandler()

Construct a new PumpStreamHandler.

PumpStreamHandler

public PumpStreamHandler(java.io.OutputStream outAndErr)

Construct a new PumpStreamHandler.

Parameters:

outAndErr - the output/error OutputStream.

PumpStreamHandler

public PumpStreamHandler(java.io.OutputStream out,
                         java.io.OutputStream err)

Construct a new PumpStreamHandler.

Parameters:

out - the output OutputStream.

err - the error OutputStream.

PumpStreamHandler

public PumpStreamHandler(java.io.OutputStream out,
                         java.io.OutputStream err,
                         java.io.InputStream input)

Construct a new PumpStreamHandler.

Parameters:

out - the output OutputStream.

err - the error OutputStream.

input - the input InputStream.

Method Detail

setStopTimeout

public void setStopTimeout(long timeout)

Set maximum time to wait until output streams are exchausted when stop() was called.

Parameters:

timeout - timeout in milliseconds or zero to wait forever (default)

setProcessOutputStream

public void setProcessOutputStream(java.io.InputStream is)

Set the InputStream from which to read the standard output of the process.

Specified by:

setProcessOutputStream in interface ExecuteStreamHandler

Parameters:

is - the InputStream.

setProcessErrorStream

public void setProcessErrorStream(java.io.InputStream is)

Set the InputStream from which to read the standard error of the process.

Specified by:

setProcessErrorStream in interface ExecuteStreamHandler

Parameters:

is - the InputStream.

setProcessInputStream

public void setProcessInputStream(java.io.OutputStream os)

Set the OutputStream by means of which input can be sent to the process.

Specified by:

setProcessInputStream in interface ExecuteStreamHandler

Parameters:

os - the OutputStream.

start

public void start()

Start the Threads.

Specified by:

start in interface ExecuteStreamHandler

stop

public void stop()
          throws java.io.IOException

Stop pumping the streams. When a timeout is specified it it is not guaranteed that the pumper threads are cleanly terminated.

Specified by:

stop in interface ExecuteStreamHandler

Throws:

java.io.IOException - thrown when an I/O exception occurs.

getErr

protected java.io.OutputStream getErr()

Get the error stream.

Returns:

OutputStream.

getOut

protected java.io.OutputStream getOut()

Get the output stream.

Returns:

OutputStream.

createProcessOutputPump

protected void createProcessOutputPump(java.io.InputStream is,
                                       java.io.OutputStream os)

Create the pump to handle process output.

Parameters:

is - the InputStream.

os - the OutputStream.

createProcessErrorPump

protected void createProcessErrorPump(java.io.InputStream is,
                                      java.io.OutputStream os)

Create the pump to handle error output.

Parameters:

is - the InputStream.

os - the OutputStream.

createPump

protected java.lang.Thread createPump(java.io.InputStream is,
                                      java.io.OutputStream os)

Creates a stream pumper to copy the given input stream to the given output stream. When the 'os' is an PipedOutputStream we are closing 'os' afterwards to avoid an IOException ("Write end dead").

Parameters:

is - the input stream to copy from

os - the output stream to copy into

Returns:

the stream pumper thread

createPump

protected java.lang.Thread createPump(java.io.InputStream is,
                                      java.io.OutputStream os,
                                      boolean closeWhenExhausted)

Creates a stream pumper to copy the given input stream to the given output stream.

Parameters:

is - the input stream to copy from

os - the output stream to copy into

closeWhenExhausted - close the output stream when the input stream is exhausted

Returns:

the stream pumper thread

stopThread

protected void stopThread(java.lang.Thread thread,
                          long timeout)

Stopping a pumper thread. The implementation actually waits longer than specified in 'timeout' to detect if the timeout was indeed exceeded. If the timeout was exceeded an IOException is created to be thrown to the caller.

Parameters:

thread - the thread to be stopped

timeout - the time in ms to wait to join

createSystemInPump

private java.lang.Thread createSystemInPump(java.io.InputStream is,
                                            java.io.OutputStream os)

Creates a stream pumper to copy the given input stream to the given output stream.

Parameters:

is - the System.in input stream to copy from

os - the output stream to copy into

Returns:

the stream pumper thread