The destroyApp() function won't execute after AT^SJNET command | Telit Cinterion IoT Developer Community

 package Example;

import com.cinterion.io.ATCommand;
import com.cinterion.io.ATCommandFailedException;
import java.io.IOException;

import javax.microedition.midlet.*;

public class BGSExample extends MIDlet {

    ApplicationTask appTask;

    public BGSExample() {
    }

    public void startApp() throws MIDletStateChangeException {
        synchronized (BGSExample.class) {
            System.out.println("BGSExample: startApp");

            String apn = "internet";
            String user = "internet";
            String password = "internet";

            try {
                ATCommand atc = new ATCommand(false);

                /* when you comment this line everything works  */
                atc.send("AT^SJNET=\"gprs\",\"" + apn + "\",\"" + user + "\",\"" + password + "\"\r");

                atc.release();
            } catch (ATCommandFailedException ex) {
                ex.printStackTrace();
            } catch (IllegalStateException ex) {
                ex.printStackTrace();
            } catch (IllegalArgumentException ex) {
                ex.printStackTrace();
            } catch (IOException ex) {
                ex.printStackTrace();
            }

            appTask = new ApplicationTask();
            appTask.start();

            System.out.println("BGSExample: startApp exit");
        }
    }

    class ApplicationTask extends Thread {

        private volatile boolean stopRequest;

        public void stopTask() {
            stopRequest = true;
        }

        public void run() {
            System.out.println("Application Task Started");
            while (!stopRequest) {
                try {
                    System.out.println("Application alive");
                    Thread.sleep(2000);
                } catch (InterruptedException ex) {
                    System.out.println("Application interrupted");
                }
            }
            System.out.println("Application Task exit");
        }
    }

    public void pauseApp() {
        System.out.println("BGSExample: pauseApp()");
    }

    public void destroyApp(boolean cond) {
        synchronized (BGSExample.class) {
            System.out.println("BGSExample: destroyApp(" + cond + ")");

            try {
                appTask.stopTask();
                appTask.interrupt();
                appTask.join();
            } catch (InterruptedException ex) {
                ex.printStackTrace();
            }

            System.out.println("BGSExample: Gracefull closed");
            notifyDestroyed();
        }
    }
}

When AT^SJNET wasn't executed:
Starting emulator in execution mode
Using USB port COM3.

Connecting to module...
Initializing module for debugging...
Establishing "IP connection for remote debugging of BGSx"...
Registering ip address "192.168.244.1" of remote debugging device...
Waiting for debug device registration of "IMP_NG_BGS5_REMOTE"...
Passing control to external device emulator...
Installing suite from: http://192.168.244.2:27855/BGSExample.jad
BGSExample: startApp
BGSExample: startApp exit
Application Task Started
Application alive
Application alive
Application alive
Application alive
Application alive
Starting emulator in execution mode
Registering ip address "192.168.244.1" of remote debugging device...
Waiting for debug device registration of "IMP_NG_BGS5_REMOTE"...
Passing control to external device emulator...
Installing suite from: http://192.168.244.2:27906/BGSExample.jad
Application alive
BGSExample: destroyApp(true)
Application interrupted
Application Task exit
BGSExample: Gracefull closed
MIDlet:Example.BGSExample terminated
BGSExample: startApp
BGSExample: startApp exit
Application Task Started
Application alive