I cool mouse robot system that works great. May work for you as well.

mouse_robot.java

public class MouseRobot {
private void mouseRebotReplace(MouseEvent e) {

int x = e.getX() - pCenterX;
int y = e.getY() - pCenterY;

if (!isPaused) {
if (mouseX < 0) {
mouseX = 0;
} else if (mouseX > pWidth) {
mouseX = pWidth;
} else if (mouseY < 0) {
mouseY = 0;
} else if (mouseY > pHeight) {
mouseY = pHeight;
} else {
mouseX += x;
mouseY += y;
}

try {
robot = new Robot();
robot.mouseMove(mouseCenterX, mouseCenterY);
} catch (AWTException e1) {
e1.printStackTrace();
}
}
}
private void mouseRebotReplace(MouseEvent e) {

int x = e.getX() - pCenterX;
int y = e.getY() - pCenterY;

if (!isPaused) {
if (mouseX < 0) {
mouseX = 0;
} else if (mouseX > pWidth) {
mouseX = pWidth;
} else if (mouseY < 0) {
mouseY = 0;
} else if (mouseY > pHeight) {
mouseY = pHeight;
} else {
mouseX += x;
mouseY += y;
}

try {
robot = new Robot();
robot.mouseMove(mouseCenterX, mouseCenterY);
} catch (AWTException e1) {
e1.printStackTrace();
}
}
}
}