org.jolokia.jvmagent.client.util

Class VirtualMachineHandler

java.lang.Object

org.jolokia.jvmagent.client.util.VirtualMachineHandler

public class VirtualMachineHandler
extends Object

A handler for dealing with VirtualMachine without directly referencing internally the class type. All lookup is done via reflection.

Since:

12.08.11

Author:

roland

Constructor Summary

Constructors

Constructor and Description
VirtualMachineHandler(OptionsAndArgs pOptions) Constructor with options

Method Summary

Methods

Modifier and Type	Method and Description
Object	attachVirtualMachine() Lookup and create a com.sun.tools.attach.VirtualMachine via reflection.
void	detachAgent(Object pVm) Detach from the virtual machine
ProcessDescription	findProcess(Pattern pPattern) Filter the process list for a regular expression and returns the description.
List<ProcessDescription>	listProcesses() Return a list of all Java processes

Methods inherited from class java.lang.Object

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

Constructor Detail

VirtualMachineHandler

public VirtualMachineHandler(OptionsAndArgs pOptions)

Constructor with options

Parameters:

pOptions - options for getting e.g. the process id to attach to

Method Detail

attachVirtualMachine

public Object attachVirtualMachine()

Lookup and create a com.sun.tools.attach.VirtualMachine via reflection. First, a direct lookup via Class.forName(String) is done, which will succeed for JVM on OS X, since tools.jar is bundled there together with classes.zip. Next, tools.jar is tried to be found (by examine java.home) and an own classloader is created for looking up the VirtualMachine. If lookup fails, a message is printed out (except when '--quiet' is provided)

Returns:

the create virtual machine of null if none could be created

detachAgent

public void detachAgent(Object pVm)

Detach from the virtual machine

Parameters:

pVm - the virtual machine to detach from

listProcesses

public List<ProcessDescription> listProcesses()
                                       throws NoSuchMethodException,
                                              InvocationTargetException,
                                              IllegalAccessException

Return a list of all Java processes

Returns:

list of java processes

Throws:

NoSuchMethodException - reflection error

InvocationTargetException - reflection error

IllegalAccessException - reflection error

findProcess

public ProcessDescription findProcess(Pattern pPattern)
                               throws InvocationTargetException,
                                      NoSuchMethodException,
                                      IllegalAccessException

Filter the process list for a regular expression and returns the description. The process this JVM is running in is ignored. If more than one process or no process is found, an exception is raised.

Parameters:

pPattern - regular expression to match

Returns:

a process description of the one process found but never null

Throws:

IllegalArgumentException - if more than one or no process has been found.

InvocationTargetException

NoSuchMethodException

IllegalAccessException