1、设计一个Dog类,有名字、颜色、年龄等属性,定义构造方法来初始化类的这些属性,定义方法输出Dog信息,编写应用程序使用Dog类。 代码: package core; public class homework1 { public static void main(String[] args) { // TODO 自动生成的方法存根 Dog dog=new Dog("黑贝","黑棕色",5); System.out.println(dog); } } class Dog { private String name; private String color; private int age; public String getName(){ return name; } public String getColor(){ return color; } public int getAge(){ return age; } public void setName(String name){ this.name=name; } public void setColor(String color){ this.color=color; } public void setAge(int age){ this.age=age; } public Dog(String name,String color,int age){ super(); this.name=name; this.color=color; this.age=age; } public String toString(){ return "狗的名字:"+this.name+",狗的颜色:"+this.color+",狗的年龄:"+this.age; } } 2、设计一个表示用户的User类,类中的变量有用户名、口令和记录用户个数的变量,定义类的3个构造方法(无参、为用户名赋值、为用户名和口令赋值)、获取和设置口令的方法和返回类信息的方法。 代码: package core; public class homework2 { public static void main(String[] args) { // TODO 自动生成的方法存根 User user1=new User("大魔王","12345678"); user1.print(); User user2=new User("小魔王","87654321"); user2.print(); new User().count(); } } class User { private String name; private String password; private static int count; public User(){ count++; } public User(String name){ this.name=name; count++; } public User(String name,String password){ this.name=name; this.password=password; count++; } public String getName(){ return name; } public void setName(String name){ this.name=name; } public String getPassword(){ return password; } public void setPassword(String password){ this.password=password; } public void print(){ System.out.println("用户名:"+name+"\t"+"口令:"+password); } public void count(){ System.out.println("用户个数:"+(count-1)); } }