I was asked by somebody in the office to extend JMeter so that when running
tests, and threads stop (due to failure) to make a way to restart the thread. 
What I have done is to create a new Visualizer that lists all the running
threads, and allows you to right click on them in the list and stop/restart
them.  However, this required a few changes to the way JMeter works.  

1.    When the initial parsing of the test tree occurs, a new

traverser was added that passed an instance of the engine being used to all test
plan tree objects that are derived from AbstractVisualizer.

2.    AbstractVisualizer was extended to receive the engine instance.

3.    StandardJMeterEngine was extended to be able to restart threads,

and accept JMeterEngineMonitors.

4.    JMeterThread was extended to fire events to JMeterThreadMonitor

(which was also extended) to indicate when it started.

5.    A new class JMeterEngineMonitor was created to monitor when

engines create threads, when their threads are stopped, and when the test
starts/stops.

6.    New visualizer class ThreadWatcherVisualizer, and

ThreadWatcherTableDataModel were created for the GUI.

7.    messeages.properties was modified to add the extra strings for

the visualizer.


The visualizer is used by addeding it to the test plan, then when a test is
running, you can see/change the running status of all the threads.

When all threads are stopped - the test stops.  I have attached a patch file to
this email. 

- Nnamdi