面向过程就是分析出解决问题所需要的步骤，然后用函数把这些步骤一步一步实现，使用的时候一个一个依次调用就可以了。
面向对象是把构成问题事务分解成各个对象，建立对象的目的不是为了完成一个步骤，而是为了描叙某个事物在整个解决问题的步骤中的行为。
例子：猜数字游戏
class GuessGame{
Player p1;
Player p2;
Player p3;//用3个实例变量分别表示3个player对象
public void startGame() {
p1=new Player();
p2=new Player();
p3=new Player();//创建出player对象
int guessp1=0;
int guessp2=0;
int guessp3=0;//声明3个变量来保存是否猜中
boolean p1isRight=false;
boolean p2isRight=false;
boolean p3isRight=false;//声明3个变量来保存猜测的数字
int targetNumber = (int)(Math.random()*10);
System.out.println("I'm thinking of a number between 0 and 9...");//产生谜底数字
while(true) {
System.out.println("Number to guess is "+targetNumber);
p1.guess();
p2.guess();
p3.guess();//调用Player的guess()方法
guessp1=p1.number;
System.out.println("Player one guessed "+guessp1);
guessp2=p2.number;
System.out.println("Player one guessed "+guessp2);
guessp3=p3.number;
System.out.println("Player one guessed "+guessp3);//取得每个Player所猜测的数字并将它列出
if(guessp1==targetNumber) {
p1isRight = true;
}
if(guessp2==targetNumber) {
p2isRight = true;
}
if(guessp3==targetNumber) {
p3isRight = true;
}//检查是否猜中，若是猜中则去设定是否猜中的变量
if(p1isRight||p2isRight||p3isRight) {//如果有一或多个猜中
System.out.println("We have a winner!");
System.out.println("Player one got it right? "+p1isRight);
System.out.println("Player two got it right? "+p2isRight);
System.out.println("Player three got it right? "+p3isRight);
System.out.println("Game is over");
break;
}else {//不然的话就重复循环继续猜下去
//都没猜到，所以要继续下去
System.out.println("Players will have to try again.");
}//if/else结束
}//循环结束
}//方法结束
}//类结束
class Player{
int number = 0;
public void guess() {
number = (int)(Math.random()*10);
System.out.println("I'm guessing "+number);
}
}
public class hm{
public static void main(String[] args) {
GuessGame game = new GuessGame();
game.startGame();
}
}
