How to get a stack in a mobile device?

Question

I get a NullPointerException in Nokia S40.

I want to know what causes this exception.

The device shows:

NullPointerException java / lang / NullPointerException

This error occurs only in the device running in the emulator, the application works fine.

I use microlog to debug my application. But the application works fine if the log is enabled.

Is there a way to get the stack trace when I get this NullPointerException? I do not need all the data, such as line number, which method raises this exception.

UPDATE: I installed the same application in another Nokia S40, and this error did not occur.

• Nokia 2660 - error
• Nokia 6131 - no errors

2:. - , NullPointerException.

    import javax.microedition.lcdui.Canvas;
    import javax.microedition.lcdui.Graphics;

    public class OuterClass extends Canvas {

    private Config config;

    public OuterClass() {
        this.config = new Config();
    }

    public void paint(Graphics graphics) {
        HelperClass helper = new HelperClass(this.config);
        helper.doStuff();
    }

    public void dispose() {
        this.config = null;
    }

    public class Config implements IConfig {
        public int getSomething() {
            // ...
        }
    }
}


 public class HelperClass {

        private IConfig config;

        public HelperClass(IConfig) {
            this.config = config;
        }

        public doStuff() {
            config.getSomething(); // Here is thrown NullPointerException
        }
    }

OuterClass.dispose() helper.doStuff(), NPE. , , , helper.doStuff() , , .

Answer 1

Throwable Nokia Series40.

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Answer 2

, . exception printStackTrace, , .

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Answer 3

Microlog .

Microlog

Answer 4

You can try to catch the exception in some high-level try / catch block, and then email the trace to yourself.