How can I create a global Robot variable without throwing an AWTException?

Question

I'm trying to create a global Robot variable in a Java class without throwing an AWTException. The only way that I can come up with it is by throwing the exception. The reason I need it to be global is because I need to use the same Robot variable in other methods in the class.

public class Robo{
    Robot r;

    public Robo() throws AWTException{
        r = new Robot();
    }

    public void useRobot(){       
        r.mouseMove(5, 5);
        r.toString();
    }

    public void useRobot2(){
        //r....some other things
    }
}

If I don't throw the exception, I need to declare a new Robot in every method.

public class Robo{

    public Robo() {

    }

    public void useRobot(){
        try{
            Robot r = new Robot();
            r.mouseMove(5, 5);
            r.toString();
        }
        catch (AWTException e){}
    }

    public void useRobot2(){
        try{
            Robot r = new Robot();
            r...... //some other things
        }
        catch (AWTException e){}
    }
}

Can somebody help me?

Answer 1

Just use the throws AWTException version, as java.awt.Robot only throws this exception when GraphicsEnvironment.isHeadless() is true.

Which means you can't run your app with Robot anyway.

Answer 2

Is there a reason you can't catch the AWTException in the constructor and throw it wrapped inside a RuntimeException?

public Robo() {
    try {
        r = new Robot();
    } catch(AWTException e) {
        throw new RuntimeException("Failed to create java.awt.Robot for Robo instance", e);
    }
}

Answer 3

use a static initializer block in your Robo class like this:

public static Robot r;

static
{
    try {
        r = new Robot();
    } catch(AWTException e){e.printStrackTrace();}
}

This makes sure the Robot class is initialized as soon as the JVM loads the Robo class file