tcl.lang.process
Class TclProcess

java.lang.Object
  tcl.lang.process.TclProcess

Direct Known Subclasses:

JavaProcess

public abstract class TclProcess
extends Object

This abstract class represents a process that may be executed from Tcl. Individual platforms should create a subclass of TclProcess, which is instantiated with with TclProcess.newInstance(). This class is somewhat of a combination of java.lang.ProcessBuilder and java.lang.Process, with inspiration from the Java 1.7 API. It is provided to allow for better native process control than Java's APIs.

Author:

Dan Bodoh

Field Summary

protected List<String>	command The command words that will be executed
protected Interp	interp The current interpreter
protected IOException	savedException An exception to be thrown in the main thread, but caught in any child thread
protected Redirect	stderrRedirect A tcl.lang.process.Redirect object specifying where stderr is redirected to
protected Redirect	stdinRedirect A tcl.lang.process.Redirect object specifying where stdin is redirected from
protected Redirect	stdoutRedirect A tcl.lang.process.Redirect object specifying where stdout is redirected to

Constructor Summary

TclProcess()

Method Summary

abstract boolean	canInheritFileDescriptors()
List<String>	command()
abstract void	destroy() Kill the running process
abstract int	exitValue()
protected Map<String,String>	getenv()
abstract int	getPid()
Redirect	getStderrRedirect()
Redirect	getStdinRedirect()
Redirect	getStdoutRedirect()
protected abstract int	implWaitFor() Platform-specific wait for the process to complete
abstract boolean	isStarted()
static TclProcess	newInstance(Interp interp) Create a new platform-specific instance of a TclProcess subclass.
protected void	saveIOException(IOException e)
void	setCommand(List<String> command) Set the command words to be executed
void	setStderrRedirect(Redirect stderrRedirect)
void	setStdinRedirect(Redirect stdinRedirect)
void	setStdoutRedirect(Redirect stdoutRedirect)
abstract void	setWorkingDir(File workingDir)
abstract void	start() Start the process executing, and register streams with any STREAM redirects
protected void	throwAnyExceptions()
int	waitFor() Wait for the process to complete

Methods inherited from class java.lang.Object

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

Field Detail

stdinRedirect

protected Redirect stdinRedirect

A tcl.lang.process.Redirect object specifying where stdin is redirected from

stdoutRedirect

protected Redirect stdoutRedirect

A tcl.lang.process.Redirect object specifying where stdout is redirected to

stderrRedirect

protected Redirect stderrRedirect

A tcl.lang.process.Redirect object specifying where stderr is redirected to

command

protected List<String> command

The command words that will be executed

interp

protected Interp interp

The current interpreter

savedException

protected IOException savedException

An exception to be thrown in the main thread, but caught in any child thread

Constructor Detail

TclProcess

public TclProcess()

Method Detail

newInstance

public static TclProcess newInstance(Interp interp)

Create a new platform-specific instance of a TclProcess subclass. This method detects the current platform and returns an instance of the appropriate TclProcess subclass.

Parameters:

interp - The current interpreter

Returns:

A platform-specific TclProcess subclass instance

setCommand

public void setCommand(List<String> command)

Set the command words to be executed

Parameters:

command - Command words to be executed

command

public List<String> command()

Returns:

The command words to be executed

getenv

protected Map<String,String> getenv()

Returns:

a unmodifiable Map containing the environment that the subprocess should inherit. System.getenv() is not sufficient because JTcl cannot update it on env() array changes.

start

public abstract void start()
                    throws IOException

Start the process executing, and register streams with any STREAM redirects

Throws:

IOException

exitValue

public abstract int exitValue()
                       throws IllegalThreadStateException

Returns:

The process's exit value

Throws:

IllegalThreadStateException - if the process has not yet completed

waitFor

public int waitFor()
            throws IllegalThreadStateException,
                   InterruptedException,
                   IOException

Wait for the process to complete

Returns:

this process's exit value

Throws:

IllegalThreadStateException - if the process has not yet been started

InterruptedException - if the process is interrupted

IOException

implWaitFor

protected abstract int implWaitFor()
                            throws InterruptedException,
                                   IOException

Platform-specific wait for the process to complete

Returns:

this process's exit value

Throws:

InterruptedException - if the process is interrupted

IOException

getPid

public abstract int getPid()
                    throws IllegalThreadStateException

Returns:

The process identifier of this process, or -1 if it cannot be determined

Throws:

IllegalThreadStateException - if the process has not yet started

isStarted

public abstract boolean isStarted()

Returns:

true if the process has started; false otherwise

setWorkingDir

public abstract void setWorkingDir(File workingDir)

Parameters:

workingDir - Directory the process starts in

destroy

public abstract void destroy()

Kill the running process

canInheritFileDescriptors

public abstract boolean canInheritFileDescriptors()

Returns:

true if the this TclProcess subclass can actually inherit the open file descriptors, or false if it emulates inheritance

getStdinRedirect

public Redirect getStdinRedirect()

Returns:

the stdinRedirect

saveIOException

protected void saveIOException(IOException e)

Parameters:

e - Exception to throw later in the main thread

throwAnyExceptions

protected void throwAnyExceptions()
                           throws IOException

Throws:

Exception - if any exception was passed to saveException()

IOException

setStdinRedirect

public void setStdinRedirect(Redirect stdinRedirect)
                      throws TclException

Parameters:

stdinRedirect - the stdinRedirect to set

Throws:

TclException

getStdoutRedirect

public Redirect getStdoutRedirect()

Returns:

the stdoutRedirect

setStdoutRedirect

public void setStdoutRedirect(Redirect stdoutRedirect)
                       throws TclException

Parameters:

stdoutRedirect - the stdoutRedirect to set

Throws:

TclException

getStderrRedirect

public Redirect getStderrRedirect()

Returns:

the stderrRedirect

setStderrRedirect

public void setStderrRedirect(Redirect stderrRedirect)
                       throws TclException

Parameters:

stderrRedirect - the stderrRedirect to set

Throws:

TclException