Make your own Prism Debuger by JPDA/JDI

Debuger.java

package test;

import java.util.ArrayList;
import java.util.Date;
import java.util.Map;

import com.sun.jdi.Bootstrap;
import com.sun.jdi.ObjectReference;
import com.sun.jdi.Value;
import com.sun.jdi.VirtualMachine;
import com.sun.jdi.VirtualMachineManager;
import com.sun.jdi.connect.AttachingConnector;
import com.sun.jdi.connect.Connector;
import com.sun.jdi.event.ClassPrepareEvent;
import com.sun.jdi.event.Event;
import com.sun.jdi.event.EventQueue;
import com.sun.jdi.event.EventSet;
import com.sun.jdi.event.ModificationWatchpointEvent;
import com.sun.jdi.event.VMDeathEvent;
import com.sun.jdi.event.VMDisconnectEvent;
import com.sun.jdi.request.ClassPrepareRequest;
import com.sun.jdi.request.ModificationWatchpointRequest;

public class Debuger {

  private static final String KERNEL_CLASS_NAME = "com.micromethod.common.server.kernel.KernelImpl";

  private static final String STATE_CLASS_NAME = "com.micromethod.common.util.state.State";

  public static void main(final String[] args) throws Exception {

    final VirtualMachineManager vmManager = Bootstrap.virtualMachineManager();
    AttachingConnector connector = null;
    for (final Connector c : vmManager.attachingConnectors()) {
      if ("com.sun.jdi.SocketAttach".equals(c.name())) {
        connector = (AttachingConnector) c;
        break;
      }
    }

    final Map<String, Connector.Argument> connectorArgs = connector.defaultArguments();
    final Connector.Argument pidArgument = connectorArgs.get("port");
    pidArgument.setValue("8000");

    final VirtualMachine vm = connector.attach(connectorArgs);

    System.out.println("----------------------------------------------");
    System.out.println(vm.description());
    System.out.println("----------------------------------------------");
    System.out.println("");

    final ClassPrepareRequest reqKernel = vm.eventRequestManager().createClassPrepareRequest();
    reqKernel.addClassFilter(KERNEL_CLASS_NAME);
    reqKernel.setEnabled(true);

    final EventQueue queue = vm.eventQueue();
    boolean running = true;
    while (running) {
      final EventSet events = queue.remove();
      for (final Event event : events) {
        if (event instanceof ClassPrepareEvent) {
          final ModificationWatchpointRequest modificationWatchpointRequest = vm.eventRequestManager()
              .createModificationWatchpointRequest(((ClassPrepareEvent) event).referenceType().fieldByName("_state"));
          modificationWatchpointRequest.setEnabled(true);
        }
        else if (event instanceof ModificationWatchpointEvent) {
          final ModificationWatchpointEvent modEvent = (ModificationWatchpointEvent) event;
          final ObjectReference oldRef = (ObjectReference) modEvent.valueCurrent();
          final ObjectReference newRef = (ObjectReference) modEvent.valueToBe();

          System.out.println("["
              + new Date()
              + "]# "
              + "Prism Kernel: "
              + (oldRef == null ? "\"UNKNOW\"" : oldRef.invokeMethod(((ModificationWatchpointEvent) event).thread(), vm
                  .classesByName(STATE_CLASS_NAME).get(0).methodsByName("name").get(0), new ArrayList<Value>(),
                  ObjectReference.INVOKE_NONVIRTUAL))
              + " -> "
              + (newRef == null ? "\"UNKNOW\"" : newRef.invokeMethod(((ModificationWatchpointEvent) event).thread(), vm
                  .classesByName(STATE_CLASS_NAME).get(0).methodsByName("name").get(0), new ArrayList<Value>(),
                  ObjectReference.INVOKE_NONVIRTUAL)));
        }
        else if (event instanceof VMDeathEvent || event instanceof VMDisconnectEvent) {
          System.out.println("");
          System.out.println("----------------------------------------------");
          System.out.println("Prism Exit.");
          System.out.println("----------------------------------------------");
          running = false;
          break;
        }
      }
      events.resume();
    }

  }
}