org.gridgain.grid.util

Class GridJavaProcess

java.lang.Object

org.gridgain.grid.util.GridJavaProcess

public final class GridJavaProcess
extends Object

Wrapper class around the Process suited to run any Java class as separate java process.

This launcher supports simple interchange-with-a-process protocol to talk (in fact, listen) to process. For the moment the only message in protocol is run process PID. Class-to-run should print it's PID prefixed with #PID_MSG_PREFIX to tell the GridJavaProcess it's PID.

Protocol transport is any of (or both) system.out and/or system.err, so any protocol message should be printed in the class-to-run.

NOTE 1: For the moment inner class running is not supported.

NOTE 2: This util class should work fine on Linux, Mac OS and Windows.

Field Summary

Fields

Modifier and Type	Field and Description
static String	PID_MSG_PREFIX Internal protocol message prefix saying that the next text in the outputted line is pid.

Method Summary

Methods

Modifier and Type	Method and Description
static GridJavaProcess	exec(Class cls, String params, GridLogger log, GridInClosure<String> printC, GridAbsClosure procKilledC) Executes main() method of the given class in a separate system process.
static GridJavaProcess	exec(Class cls, String params, GridLogger log, GridInClosure<String> printC, GridAbsClosure procKilledC, Collection<String> jvmArgs, String cp) Executes main() method of the given class in a separate system process.
int	getPid() Returns pid of the java process.
Process	getProcess() Exposes wrapped java Process.
void	kill() Kills the java process.

Methods inherited from class java.lang.Object

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

Field Detail

PID_MSG_PREFIX

public static final String PID_MSG_PREFIX

Internal protocol message prefix saying that the next text in the outputted line is pid.

See Also:

Constant Field Values

Method Detail

exec

public static GridJavaProcess exec(Class cls,
                   String params,
                   @Nullable
                   GridLogger log,
                   @Nullable
                   GridInClosure<String> printC,
                   @Nullable
                   GridAbsClosure procKilledC)
                            throws Exception

Executes main() method of the given class in a separate system process.

Parameters:

cls - Class with main() method to be run.

params - main() method parameters.

printC - Optional closure to be called each time wrapped process prints line to system.out or system.err.

procKilledC - Optional closure to be called when process termination is detected.

log - Log to use.

Returns:

Wrapper around Process

Throws:

Exception - If any problem occurred.

exec

public static GridJavaProcess exec(Class cls,
                   String params,
                   @Nullable
                   GridLogger log,
                   @Nullable
                   GridInClosure<String> printC,
                   @Nullable
                   GridAbsClosure procKilledC,
                   @Nullable
                   Collection<String> jvmArgs,
                   @Nullable
                   String cp)
                            throws Exception

Executes main() method of the given class in a separate system process.

Parameters:

cls - Class with main() method to be run.

params - main() method parameters.

printC - Optional closure to be called each time wrapped process prints line to system.out or system.err.

procKilledC - Optional closure to be called when process termination is detected.

log - Log to use.

jvmArgs - JVM arguments to use.

cp - Additional classpath.

Returns:

Wrapper around Process

Throws:

Exception - If any problem occurred.

kill

public void kill()
          throws Exception

Kills the java process.

Throws:

Exception - If any problem occurred.

getPid

public int getPid()

Returns pid of the java process. Wrapped java class should print it's PID to system.out or system.err to make wrapper know about it.

Returns:

Pid of the java process or -1 if pid is unknown.

getProcess

public Process getProcess()

Exposes wrapped java Process.

Returns:

Wrapped java process.