MultiMonTest

import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Rectangle;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;

public class MultiMonTest {

    public static void main(String[] args) {
        new MultiMonTest();
    }

    public MultiMonTest() {
        JFrame f = new JFrame();
        f.addKeyListener(new KeyListener() {
            @Override
            public void keyTyped(KeyEvent e) {}

            @Override
            public void keyPressed(KeyEvent e) {
                if(e.getKeyChar() == ' ') {
                    prevMonitor(f);
                } else if(e.getKeyChar() == '\n') {
                    nextMonitor(f);
                }
            }

            @Override
            public void keyReleased(KeyEvent e) {}
        });
        f.setSize(256, 256);
        new Thread(() -> {
            while(true) {
                try {
                    Thread.sleep(1000);
                    GraphicsDevice device = f.getGraphicsConfiguration().getDevice();
                    GraphicsDevice[] screenArray = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();
                    int index = findDeviceIndex(device);
                    for(int i = 0; i < screenArray.length; i++) {
                        if(screenArray[i].equals(device)) {
                            index = i;
                            break;
                        }
                    }
                    System.out.println(device + " " + (index+1) + "/" + screenArray.length + ": " + f.getX() + ", " + f.getY());
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }).start();
        f.setVisible(true);
    }

    private int findDeviceIndex(GraphicsDevice device) {
        GraphicsDevice[] screenArray = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();
        for(int i = 0; i < screenArray.length; i++) {
            if(screenArray[i].equals(device)) {
                return i;
            }
        }
        return -1;
    }

    private void nextMonitor(JFrame f) {
        GraphicsDevice[] screenArray = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();
        GraphicsDevice device = f.getGraphicsConfiguration().getDevice();
        GraphicsDevice newDevice = null;
        int index = findDeviceIndex(device);
        if(index == screenArray.length - 1) {
            newDevice = screenArray[0];
        } else {
            newDevice = screenArray[++index];
        }

        Rectangle r = newDevice.getDefaultConfiguration().getBounds();
        f.setLocation(r.x, r.y);
    }

    private void prevMonitor(JFrame f) {
        GraphicsDevice[] screenArray = GraphicsEnvironment.getLocalGraphicsEnvironment().getScreenDevices();
        GraphicsDevice device = f.getGraphicsConfiguration().getDevice();
        GraphicsDevice newDevice = null;
        int index = findDeviceIndex(device);
        if(index == 0) {
            newDevice = screenArray[screenArray.length - 1];
        } else {
            newDevice = screenArray[--index];
        }

        Rectangle r = newDevice.getDefaultConfiguration().getBounds();
        f.setLocation(r.x, r.y);
    }

}