1.4: Objects as Return Types

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The java.awt package also provides a class called Rectangle. To use it, you have to import it:

import java.awt.Rectangle;

Rectangle objects are similar to points, but they have four attributes: x, y, width, and height. The following example creates a Rectangle object and makes the variable box refer to it:

Rectangle box = new Rectangle(0, 0, 100, 200);

Figure 10.4.1 shows the effect of this assignment.

State diagram showing a Rectangle object. — **Figure** \(\PageIndex{1}\): State diagram showing a `Rectangle` object.

If you run System.out.println(box), you get:

java.awt.Rectangle[x=0,y=0,width=100,height=200]

Again, println uses the toString method provided by Rectangle, which knows how to display Rectangle objects.

You can write methods that return objects. For example, findCenter takes a Rectangle as an argument and returns a Point with the coordinates of the center of the rectangle:

public static Point findCenter(Rectangle box) {
    int x = box.x + box.width / 2;
    int y = box.y + box.height / 2;
    return new Point(x, y);
}

The return type of this method is Point. The last line creates a new Point object and returns a reference to it.