Name: acR10002 Date: 12/03/2000


The Rectangle.intersects(Rectangle) method will behave incorrectly if rectangle
object has been created in (or put into) the state then it's limits are out of integer
range, i.e. x + width > Integer.MAX_VALUE or y + height > Integer.MAX_VALUE. Below
is one or more examples :

------ Test1.java ------------

import java.awt.Rectangle;

public class Test1 {
    public static void main(String args[]) {
Rectangle r = new Rectangle(1, 0, Integer.MAX_VALUE, 1);
if (r.intersects(r)) {
System.out.println("OKAY: rectangle intersects itself");
} else {
System.out.println("FAILURE: rectangle doesn't intersect itself"); }
    }
}

------------------------------
--> java Test1
FAILURE: rectangle doesn't intersect itself

This happens due to an int overflow during calculations. The same problem may happen to
contains(int,int) and contains(int,int,int,int) methods, for example:

------ Test2.java ------------
import java.awt.Rectangle;

public class Test2 {
    public static void main(String args[]) {
Rectangle r = new Rectangle(1, 0, Integer.MAX_VALUE, 1);
if (r.contains(1, 0, 1, 1)) {
System.out.println("OKAY: rectangle contains smaller one, as expected");
} else {
System.out.println("FAILURE: rectangle doesn't contain smaller one");
}
    }
}
------------------------------
--> java -classpath . Test2
FAILURE: rectangle doesn't contain smaller one

There are two possible solutions for this problem:
1. Specification should state explicitly that behavior for contains() and intersects() methods
is undefined if the limits of this rectangle or rectangle passed as an argument are out
of integer range (the similar clarification has been already made for negative width/height
rectangles).
2. Implementation should be changed to use long, for example, during internal calculations
   to avoid integer overflows.

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