JDI: How to pause a Java application (JVM) like in the debugger

Question

I am looking for potentially a JDI API to pause the JVM at any arbitrary point during its execution. Looking at the BreakPointRequest createBreakpointRequest method needs a specific location. Is there any other API that does not need a location or someway to get current Location that could be passed to create a breakpoint.

I am basically looking for a way to attach and pause the application, then use JVMTI agent to receive callback for the BreakPoint event to perform further processing. Thanks

Undervest

You want to halt JVM or application? if I understand correctly, one jvm may host multiple applications. If it is Jvm, Virtualmachine class, process method may be worth to research on for your req. – Antiphlogistic

Answer 1

Breakpoints only make sense with a location in source. Arbitrary pausing your application is probably best done by suspending all the threads currently running in the JVM. Take a look at SuspendThreadList() or SuspendThread in jvmti. This mechanism would be the 'pause' you are looking for.

Silberman

Answer 2

If you want to arbitrarily pause a running jvm with JDI, you would use the JDI VirtualMachine interface's suspend method.

However, this doesn't really give you much in terms of being able to then connect to a jvmti agent; as the other answer points out, the jvmti has its own methods for doing the same thing.

If you're looking for a way to define arbitrary callbacks for breakpoints, as opposed to calling out to a specific agent, you might be interested in jdiscript, which is a scripting layer around the JDI that lets you do such things pretty easily in straight Java, rather than having to drop into C++.

Lilytrotter

Answer 3

i think jdb - The Java Debugger will be the best option. please check the url about the jdb

http://docs.oracle.com/javase/1.3/docs/tooldocs/solaris/jdb.html

Reavis