— Scott McNealy, Sun Microsystems Chairman, President and ceo

%javac TestMath
TestMath.java:3: Math() has private 
access in java.lang.Math
Math mathObject = new Math();
^
1 error
Math mathObject = new Math();
If you try to make an instance of 
class Math:
You’ll get this error:
int x = Math.round(42.2);
int y = Math.min(56,12);
int z = Math.abs(-343);
These methods never use 
instance variables, so their 
behavior doesn’t need to 
know about a specific object.

---

numbers 
and
statics
you are here
4
275
The difference bet ween regular 
(non-static) and static methods
Java is object-oriented, but once in a while you have a special case, 
typically a utility method (like the Math methods), where there is 
no need to have an instance of the class. The keyword 
static 
lets 
a method run without any instance of the class. A static method means 
“behavior not dependent on an instance variable, so no instance/object 
is required. Just the class.”
Politik
Coldplay
Song
s2
s2.play();
s3.play();
Calling play() on this 
reference will cause 
“Politik” to play. 
Calling play() on this 
reference will cause 
“My Way” to play. 
My Way
Sex Pistols
Song
s3
Song o
bj
ec
t 
public class Song {
String title;
public Song(String t) {
title = t;
}
public void play() {
SoundPlayer player = new SoundPlayer();
player.playSound(title);
}
public static int min(int a, int b){