repicea.multiprocess

Class JavaProcess

java.lang.Object

repicea.multiprocess.JavaProcess

All Implemented Interfaces:

java.io.Serializable, java.lang.Runnable, java.util.concurrent.Future<java.lang.Integer>, IndependentProcess

public final class JavaProcess
extends java.lang.Object

This class has a design similar to the SwingWorker class. It embeds a process that is to be a Java process. The commands in the constructor majes it possible to specified the runnable jar and its options.

An exemple of an instance of this class could be

List<String> commands = new ArrayList<String>();
commands.add("myJar.jar");
JavaProcess jp = new JavaProcess(commands);
jp.execute();
int outValueFromRemoteJVM = jp.get();

The method get() waits for the process to end. The result is actually the output value of the remote Java Virtual Machine (JVM), which is usually 0 if the process ended properly. The class is designed to be run only once. Additional calls of the execute() method will not result in the instantiation of a new independent Java process. As in the SwingWorker class, this class also send PropertyChangeEvent to eventual listeners that can be added through the addPropertyChangeListener method.

Objects can be sent to the process using the method sendObjectToProcess(). The objects are sent asynchronously and may not be sent is the process ends before. The incoming stream, ie. the output stream of the remote JVM, is sent to the PropertyChangeListener instances using the "MessageReceived" property.

Finally, the class implements the Serializable interface. Actually, only some fields are serializable. A JavaProcess instance can be serialized either before or after executing the process, but not during its execution.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JavaProcess.JVM_OPTION

Nested classes/interfaces inherited from interface repicea.multiprocess.IndependentProcess

IndependentProcess.StateValue

Constructor Summary

Constructors

Constructor and Description
JavaProcess(java.util.List<java.lang.String> commands) Sub constructor with the commands only.
JavaProcess(java.util.List<java.lang.String> commands, java.io.File workingDirectory) Sub constructor with only the commands and the working directory.
JavaProcess(java.util.List<java.lang.String> commands, java.io.File workingDirectory, java.util.Map<java.lang.String,java.lang.String> environment) General constructor.
JavaProcess(java.util.List<java.lang.String> commands, java.util.Map<java.lang.String,java.lang.String> environment) Sub constructor with only the commands and the environment.

Method Summary

Modifier and Type	Method and Description
void	addPropertyChangeListener(java.beans.PropertyChangeListener listener) This method add a listener to the instance of this class if it is not already included in the listeners list.
boolean	cancel(boolean mayInterruptIfRunning)
protected java.lang.Process	createIndependentProcess() This method creates the proper Process instance according to the derived class.
void	execute() This method starts the independent process.
protected void	firePropertyChange(java.lang.String propertyName, java.lang.Object oldValue, java.lang.Object newValue)
java.lang.Integer	get()
java.lang.Integer	get(long duration, java.util.concurrent.TimeUnit timeUnit)
java.util.Map<JavaProcess.JVM_OPTION,java.lang.String>	getJVMSettings() This method returns the options of the JVM as set by the user.
java.lang.String	getName() This method returns the name of the process.
IndependentProcess.StateValue	getState() This method returns the state of the process which can be either PENDING, STARTED, or DONE.
boolean	isCancelled()
boolean	isDone()
void	redirectOutputStream(boolean redirectOutputStream) This method enables the redirection of the outputstream of the independent process into the outputstream of this outer process (this process).
void	removePropertyChangeListener(java.beans.PropertyChangeListener listener) This method removes all the instances of the listener among the listeners of this class.
void	run()
void	sendObjectToProcess(java.io.Serializable obj) This method makes it possible to send a Serializable object to the independent process, typically a callback process.
void	setClassPath(java.lang.String classPath) This method sets the classpath.
void	setJVMMemory(int nbMegaJVM) This method sets the maximum memory of the Java Virtual Machine that runs this process.
void	setName(java.lang.String name) This method sets the name of this process.
void	setOpenModuleForVersionsLaterThan8Enabled(boolean bool) Open the internal loader for versions later than 8.
void	setOption(JavaProcess.JVM_OPTION optionName, java.lang.String option) This method sets the JVM options

Methods inherited from class java.lang.Object

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

Constructor Detail

JavaProcess

public JavaProcess(java.util.List<java.lang.String> commands,
                   java.io.File workingDirectory,
                   java.util.Map<java.lang.String,java.lang.String> environment)

General constructor.

Parameters:

commands - the list of commands

workingDirectory - the working directory for the process

environment - the environment of the process

JavaProcess

public JavaProcess(java.util.List<java.lang.String> commands,
                   java.io.File workingDirectory)

Sub constructor with only the commands and the working directory.

Parameters:

commands - the list of commands

workingDirectory - the working directory for the process

JavaProcess

public JavaProcess(java.util.List<java.lang.String> commands)

Sub constructor with the commands only.

Parameters:

commands - the list of commands

JavaProcess

public JavaProcess(java.util.List<java.lang.String> commands,
                   java.util.Map<java.lang.String,java.lang.String> environment)

Sub constructor with only the commands and the environment.

Parameters:

commands - the list of commands

environment - the environment of the process

Method Detail

getName

public java.lang.String getName()

Description copied from interface: IndependentProcess

This method returns the name of the process.

Specified by:

getName in interface IndependentProcess

Returns:

a String

createIndependentProcess

protected java.lang.Process createIndependentProcess()
                                              throws java.io.IOException

This method creates the proper Process instance according to the derived class.

Returns:

a Process object

Throws:

java.io.IOException

setJVMMemory

public void setJVMMemory(int nbMegaJVM)

This method sets the maximum memory of the Java Virtual Machine that runs this process. The method does nothing if the parameter is not larger than 0.

Parameters:

nbMegaJVM - the number of MegaByte (Integer)

setClassPath

public void setClassPath(java.lang.String classPath)

This method sets the classpath. It has no effect if the first element of the command list is a jar file.

Parameters:

classPath - the complete classpath

setOpenModuleForVersionsLaterThan8Enabled

public void setOpenModuleForVersionsLaterThan8Enabled(boolean bool)

Open the internal loader for versions later than 8.

Parameters:

bool - it is set to false by default

setOption

public void setOption(JavaProcess.JVM_OPTION optionName,
                      java.lang.String option)

This method sets the JVM options

Parameters:

optionName - a JVM_OPTION enum instance

option - a String that defines the option

getJVMSettings

public java.util.Map<JavaProcess.JVM_OPTION,java.lang.String> getJVMSettings()

This method returns the options of the JVM as set by the user.

Returns:

a Map of JVM_OPTION instances and their settings.

cancel

public boolean cancel(boolean mayInterruptIfRunning)

Specified by:

cancel in interface java.util.concurrent.Future<java.lang.Integer>

get

public java.lang.Integer get()
                      throws java.lang.InterruptedException,
                             java.util.concurrent.ExecutionException

Specified by:

get in interface java.util.concurrent.Future<java.lang.Integer>

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

get

public java.lang.Integer get(long duration,
                             java.util.concurrent.TimeUnit timeUnit)
                      throws java.lang.InterruptedException,
                             java.util.concurrent.ExecutionException,
                             java.util.concurrent.TimeoutException

Specified by:

get in interface java.util.concurrent.Future<java.lang.Integer>

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

java.util.concurrent.TimeoutException

isCancelled

public boolean isCancelled()

Specified by:

isCancelled in interface java.util.concurrent.Future<java.lang.Integer>

getState

public IndependentProcess.StateValue getState()

This method returns the state of the process which can be either PENDING, STARTED, or DONE. As soon as the execute method is called the state changes from PENDING to STARTED. At the end of the process, the State shifts to DONE.

Returns:

a StateValue enum var

isDone

public boolean isDone()

Specified by:

isDone in interface java.util.concurrent.Future<java.lang.Integer>

run

public void run()

Specified by:

run in interface java.lang.Runnable

firePropertyChange

protected void firePropertyChange(java.lang.String propertyName,
                                  java.lang.Object oldValue,
                                  java.lang.Object newValue)

addPropertyChangeListener

public void addPropertyChangeListener(java.beans.PropertyChangeListener listener)

Description copied from interface: IndependentProcess

This method add a listener to the instance of this class if it is not already included in the listeners list. The listeners are communicated the changes of the state member as well as the message received from the process itself.

Specified by:

addPropertyChangeListener in interface IndependentProcess

Parameters:

listener - a PropertyChangeListener instance

removePropertyChangeListener

public void removePropertyChangeListener(java.beans.PropertyChangeListener listener)

Description copied from interface: IndependentProcess

This method removes all the instances of the listener among the listeners of this class.

Specified by:

removePropertyChangeListener in interface IndependentProcess

Parameters:

listener - a PropertyChangeListener instance

execute

public void execute()

Description copied from interface: IndependentProcess

This method starts the independent process. Can be called only once.

Specified by:

execute in interface IndependentProcess

setName

public void setName(java.lang.String name)

Description copied from interface: IndependentProcess

This method sets the name of this process.

Specified by:

setName in interface IndependentProcess

Parameters:

name - a String

sendObjectToProcess

public void sendObjectToProcess(java.io.Serializable obj)
                         throws java.io.IOException

Description copied from interface: IndependentProcess

This method makes it possible to send a Serializable object to the independent process, typically a callback process.

Specified by:

sendObjectToProcess in interface IndependentProcess

Parameters:

obj - a Serializable object

Throws:

java.io.IOException

redirectOutputStream

public void redirectOutputStream(boolean redirectOutputStream)

This method enables the redirection of the outputstream of the independent process into the outputstream of this outer process (this process). By default, the redirection is set to true.

Parameters:

redirectOutputStream - true to enable or false to disable