Joystick control Java

Question

I am building a robot simulator to simulate how the robot will move and react to friction and other outside events. I have it working using the arrow keys for input, but I am trying to get it working with a joystick. I am using slick2D per recommendation. I have never used slick2D and am very confused about how to make my program work. What classes in slick should I use?

Answer 1

According to Slick2D's forums, JInput is the preferred method for working with a Joystick.

According to java-gaming.org, JInput requires native libraries to work (.dll, .so or .dylib, depending on your platform).

Here's the example copied from java-gaming:

    /* Gets a list of the controllers JInput knows about and can interact with */
    Controller[] ca = ControllerEnvironment.getDefaultEnvironment().getControllers();

    for(int i =0;i<ca.length;i++){

        /* Get the name of the controller */
        System.out.println(ca[i].getName());

        /* Gets the type of the controller, e.g. GAMEPAD, MOUSE, KEYBOARD */
        System.out.println("Type: "+ca[i].getType().toString());

        /* Get this controllers components (buttons and axis) */
        Component[] components = ca[i].getComponents();
        System.out.println("Component Count: "+components.length);
        for(int j=0;j<components.length;j++){

            /* Get the components name */
            System.out.println("Component "+j+": "+components[j].getName());

            /* Gets its identifier, E.g. BUTTON.PINKIE, AXIS.POV and KEY.Z */

            System.out.println("    Identifier: "+ components[j].getIdentifier().getName());

            /* Display if component is relative, absolute, analog, digital */
            System.out.print("    ComponentType: ");
            if (components[j].isRelative()) {
                System.out.print("Relative");
            } else {
                System.out.print("Absolute");
            }
            if (components[j].isAnalog()) {
                System.out.print(" Analog");
            } else {
                System.out.print(" Digital");
            }
        }
    }

Getting values requires polling the device or using Event Queues.

Warning, this next block is written in an infinite loop, which can block other code from executing, a good candidate for a dedicated thread.

  while(true) {
     Controller[] controllers = ControllerEnvironment.getDefaultEnvironment().getControllers();
     if(controllers.length==0) {
        System.out.println("Found no controllers.");
        break;
     }

     for(int i=0;i<controllers.length;i++) {
        controllers[i].poll();

     EventQueue queue = controllers[i].getEventQueue();
     Event event = new Event();

     while(queue.getNextEvent(event)) {
           StringBuffer buffer = new StringBuffer(controllers[i].getName());
           buffer.append(" at ");
           buffer.append(event.getNanos()).append(", ");
           Component comp = event.getComponent();
           buffer.append(comp.getName()).append(" changed to ");
           float value = event.getValue(); 
           if(comp.isAnalog()) {
              buffer.append(value);
           } else {
              if(value==1.0f) {
                 buffer.append("On");
              } else {
                 buffer.append("Off");
              }
           }
           System.out.println(buffer.toString());
        }
     }

     try {
        Thread.sleep(20);
     } catch (InterruptedException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
     }
  }