how to move an object to the mouse in Java

I have just recently started using Java, literally 2 days ago, and I have run into an issue. While I have been easily able to figure out most of the syntax and methods, because I have used multiple other languages, I was not able to solve this problem.

Essentially, I have placed a box (it aspires to be great things one day) on the screen, what I want this box to do, is when I click anywhere on the screen, he will move to that position. In other languages I would be able to do this fairly simply, but since I am not used to Java's particular method of doing things, it has become an issue.

Basically this is what I was trying to do:

Inside my Mouse Input class (extending MouseInputAdapter)

public void mousePressed(MouseEvent e) {
      while(this.mouseIsPressed && playerObject != null){
            double newX = e.getXOnScreen();
            double newY = e.getYOnScreen();
            double distX = newX - playerObject.getX();
            double distY = newY - playerObject.getY();
            double length = Math.sqrt(((distX * distX) + (distY * distY)));
            if(length > 0){
            playerObject.setVelocityX(distX/length);
            playerObject.setVelocityY(distY/length);
            }else{
            playerObject.setVelocityX(0);
            playerObject.setVelocityY(0);
            }

            }
        }
    }

this just seems to make the object go crazy and move, god knows where.

I tried something similar with the mousemove method, because I want the object to continually follow the mouse while the mouse is pressed.

I am sure I am missing a simple fix to this, and if someone can help me with this, that would be great. Maybe there is a more efficient method in Java (this is just the method i used in other languages). I am looking more for the steps to take, than the exact code.

EDIT

So this is what I have now... In my player class:

    public void Update(){   
            if(mouseInput != null){
                boolean mousePressed = mouseInput.checkIfPressed();
                if(mousePressed){
                    double newX = mouseInput.showX();
                    double newY = mouseInput.showY();
                    double distX = newX - this.x;
                    double distY = newY - this.y;
                    double length = Math.sqrt(((distX * distX) + (distY * distY)));
                    if(length >= 1){
                        this.velocityX = distX/length;
                        this.velocityY = distY/length;
                    }else{
                        this.velocityX = 0;
                        this.velocityY = 0;
                    }
                }
            }
            x += this.velocityX;
            y += this.velocityY;
        }

and in my Mouse Input Class:

public void mousePressed(MouseEvent e) {
    mouseIsPressed = true;
    System.out.println(mouseIsPressed);
    this.e = e;
}

public void Update(){
    if(mouseIsPressed){
        X = this.e.getX();
        Y = this.e.getY();  
        System.out.println(X);
        System.out.println(Y);

    }
}
public void mouseReleased(MouseEvent e){
    mouseIsPressed = false;
    this.e = null;
    System.out.println(mouseIsPressed);


}

If there is another way to do this, it would be great, or a proper way to do this.

Thanks in advance