Simplest example with a new object

From WikiJava

There's no simpler example about java objects I could imagine.

the article

Let's suppose we would like to rappresent a rectangle, made from coordinates x = 5 and y = 10, height = 20 and width = 30. Then we would like to move it 15 units on the x axis, and 25 units on the y axis.

In Java we have a huge number of built-in completely-portable classes along with their methods. One of them rappresent a rectangle (when you write "import java.awt.Rectangle;"), with a lot of methods.

The Rectangle class describes both how to construct a rectangle with desidered values and an instance method called translate to move the rectangle (and many others built-in methods).

Il metodo translate ha due parametri formali che rappresentano lo spostamento lungo l'asse x e quello lungo l'asse y.

So we have to write a program who:

• create a rectangle (a particular rectangle with that dimensions)
• print/dump to the screen the rectangle status
• move the rectangle 15 units on the x axis, and 25 units on the y axis
• print/dump to the screen the rectangle status (to verify the change)

In other words we have to write something like this:

MoveRectangle.java

import java.awt.Rectangle;
 
public class MoveRectangle {
 
    public static void main(String[] args) {
        Rectangle rect;
        rect = new Rectangle(5, 10, 20, 30);
        System.out.println(rect);
        rect.translate(15, 25);
        System.out.println(rect);
   }
 
}

See Also

http://java.sun.com/javase/6/docs/api/java/awt/Rectangle.html

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