MaterialMaster_CreateIDOC Cannot start thread

Question

I am using the Material_Master AOI template with data services I wanted to loop through the IDOC for each plant starting with our main plant then as we loop material would be pushed (extended) to the other plants. When I looped the second time I go the error below. It appears because the connection is already opened for the IDOC another cannot thread be created. Can I close the connection when each plant is pushed and then re-open for the next plant?
7036       7160       SYS-050703         9/20/2011 2:47:24 PM    |Session Job_P2CMM01_Res_Material_Master|Work flow WF_P2CMM01_Res_MaterialMaster_GenerateIDOC|Data flow DF_P2CMM01_Res_MaterialMaster_CreateIDOC
7036       7160       SYS-050703         9/20/2011 2:47:24 PM    Cannot start thread.

Answer 1

Tasks are meant to be run in the context of a JavaFX application, like in the example below:
import javafx.application.Application;
import javafx.concurrent.Task;
import javafx.scene.Scene;
import javafx.scene.layout.StackPane;
import javafx.scene.paint.Color;
import javafx.stage.Stage;
import java.io.IOException;
public class TaskApp extends Application {
  public static void main(String[] args) { launch(args); }
  @Override public void start(final Stage stage) throws IOException {
    //create task object
    Task<Integer> task = new Task<Integer>(){
      @Override
      protected Integer call() throws Exception{
        System.out.println("Background task started...");
        int iterations;
        for(iterations = 0; iterations < 10000; iterations++){
          if(isCancelled()){
            break;
          System.out.println("Iteration " + iterations);
          Thread.sleep(3000);
        return iterations;
    //start the background task
    Thread th = new Thread(task);
    th.setDaemon(true);
    System.out.println("Starting background task...");
    th.start();
    stage.setScene(new Scene(new StackPane(), 200, 100, Color.BLANCHEDALMOND));
    stage.show();
}Also your code was setting the task thread as a daemon thread. The Java Virtual Machine exits when the only threads running are all daemon threads. So once your main routine finished (which would be really quickly), the program would just exit without doing anything much. Note that, in your example, even if you made the Task thread a non-daemon thread, it still doesn't work (likely because the Task class has some reliance on the JavaFX system being initialized). For your simple background process you could skip Task and just use a Runnable or a Callable (which doesn't require JavaFX and hence would work in a non-daemon thread invoked from main), but I guess it's just an experiment.