1、 System.out.println(); x = x + 1; Dog.javapublic class Dog String name;/变量有两种:基本数据类型和引用数据类型;变量声明时必须要有类型和名称 /创建dog对象 Dog dog1 = new Dog(); dog1.bark(); dog1.name = mark /创建dog数组 Dog mydogs = new Dog3;/数组也属于对象,数组的引用既是对象的引用 mydogs0 = new Dog(); mydogs1 = new Dog(); mydogs2 = dog1; /通过数组引用存取dog mydogs0.
2、name = tina mydogs1.name = peter /dog2的名字? System.out.println(what is the dog2s name? System.out.println(mydogs2.name); /对dog逐个执行bark()方法mydogs.length) mydogsx.bark(); public void bark() System.out.println(name + wang wang!DogTestDrive.javapublic class DogTestDrive public static void main(String arg
3、s) Dog d = new Dog();/建立一个dog对象 d.size = 40; d.bark();class Dog int size; String breed; void bark()you are a fool dog!DooBee.javapublic class DooBee int x=1; 3 ) System.out.print(DooBee x+; if(x=3)DoDrumKitTestDrive.javaclass DrumKit boolean topHat = true; boolean snare = true; void playTopHat() din
4、g ding da-ding void playSnare()bang bang ba-bangclass DrumKitTestDrive DrumKit d = new DrumKit(); d.snare = false; d.playSnare(); d.playTopHat(); if(d.snare = true) d.playSnare();EchoTestDrive.javapublic class EchoTestDrive Echo e1 = new Echo(); Echo e2 = new Echo(); 4) e1.hello(); e1.count = e1.cou
5、nt + 1; if(x = 3) e2.count = e2.count + 1; if(x0) e2.count = e2.count + e1.count; System.out.println(e2.count);class Echo int count = 0; void hello()heloooo.GameLaucher.javaclass GuessGame Player p1;/创建3个实例变量player对象 Player p2; Player p3; public void startGame()/创建startGame的方法 p1 = new Player(); p2
6、= new Player(); p3 = new Player(); int guessp1=0;/用三个变量声明是否数字被猜中 int guessp2=0; int guessp3=0; boolean p1isright = false;/声明三个变量来保存猜测的数字 boolean p2isright = false; boolean p3isright = false; int targetnumber = (int)(Math.random()*10);I am thinking of a number is:. while(true)number to guss is +targe
7、tnumber); p1.guess();/调用player的guess方法 p2.guess(); p3.guess(); guessp1 = p1.number;/取出猜的数字并且罗列出来player one gussed + guessp1); guessp2 = p2.number;player two gussed + guessp2); guessp3 = p3.number;player three gussed + guessp3); if(guessp1=targetnumber)/判断所猜的数字是否和目标数字相等 p1isright = true; if(guessp2=t
8、argetnumber) p2isright = true; if(guessp3=targetnumber) p3isright = true; if(p1isright|p2isright|p3isright) System.out.println(we have a winner!player one got it right? + p1isright);player two got it right? + p2isright);player three got it right? + p3isright);Game is over! break;/游戏结束 终止循环 else the
9、game we will come on! class Player int number = 0;/要被猜的数字 public void guess() number = (int)(Math.random()*10);/利用随机函数产生随机数I am guessing the number is + number);/主方法public class GameLaucher GuessGame game = new GuessGame();/创建GussGame的对象game game.startGame();/game对象调用startGame的方法,开始执行游戏HelloWorld.ja
10、vapublic class HelloWorld public static void main(String args)HelloWorldHobbits.javapublic class Hobbits Hobbits h = new Hobbits3; int z = -1; while(z2) z = z + 1; hz = new Hobbits(); hz.name = bilbo if(z=1) hz.name = if(z=2) System.out.println(hz.name + is a good hobbits name!IfTest.javapublic clas
11、s IfTest int x=3;x must be 3this runs no matter what!IfTest2.javapublic class IfTest2 int x=2; else x is not 3JieCheng.javapublic class JieCheng long result = 0; long f = 1; for(int i=1;i2) System.out.print(a x=x-1;- if(x=2) System.out.print(b c if(x=1) System.out.print(dSum.javapublic class Sum1到99
12、的和是:Test.javapublic class Test int num = 0,i = 1; while(i100) if(i%3=0) i=+i); num+; if(num = 5) i+;TestArrays.javapublic class TestArrays String islands = new String4; int index = new int4; int y = 0; islands0 = Bermuda islands1 = Fiji islands2 = Azores islands3 = Cozumel index0 = 1; index1 = 3; in
13、dex2 = 0; index3 = 2; int ref; while(ywangwang! numsofbark-; Dog() numsofbark=0;TestNum.javapublic class TestNum for(int i=101;200; boolean flag = true; for(int j=2;ji;j+) if(i%j=0) flag=false; if(!flag)continue;TestVar.javapublic class TestVar int j=9; int i=0; System.out.println(i); /System.out.println(j);/成员变量和局部变量