java第八次作业
package e; public class e { int x; int y; public void e() { } public e(int x0, int y0) { super(); this.x = x0; this.y = y0; } public e() { super(); } public String movee(int dx, int dy) { x = dx + x; y = dy + y; return ("x为" + x + "y为" + y); } public static void main(String[] args) { e p1 = new e(2, 5); System.out.println(p1.movee(5, 5)); e p2 = new e(4, 7); System.out.println(p2.movee(3, 7)); } }
2.定义一个矩形类Rectangle:(知识点:对象的创建和使用)[必做题]
(1)定义三个方法:getArea()求面积、getPer()求周长,showAll()分别在控制台输出长、宽、面积、周长。
(2)有2个属性:长length、宽width
(3)通过构造方法Rectangle(intwidth,intlength),分别给两个属性赋值
(4)创建一个Rectangle对象,并输出相关信息
public class e { private int length; private int width; public e() { } public e(int length,int width) { this.length=length; this.width=width; } public void getArea() { int a=length*width; System.out.println("面积为"+a); } public void getPer() { int b=2*length+2*width; System.out.println("周长为"+b); } public void showAll() { System.out.println("长为"+length+"宽为"+width); getArea(); getPer(); } public static void main(String[] args) { e c=new e(4, 6); c.getArea(); c.getPer(); c.showAll(); } }
三、定义一个笔记本类,该类有颜色(char)和cpu型号(int)两个属性。[必做题]
1.无参和有参的两个构造方法;有参构造方法可以在创建对象的同时为每个属性赋值;
2.输出笔记本信息的方法
3.然后编写一个测试类,测试笔记本类的各个方法。
package e; public e{ char colour; int cpu; public void show() { System.out.println("我的颜色是:" + colour+"色" + ",型号是:" + cpu); } public computer(char colour, int cpu) { super(); this.colour = colour; this.cpu = cpu; } public computer() { super(); } } package wen; public class test { public static void main(String[] args) { // TODO Auto-generated method stub computer s1=new computer(); s1.colour='黑'; s1.cpu=121; s1.show(); computer s2=new computer('蓝',111); s2.show(); } }
5、定义两个类,描述如下: [必做题] • 5.1定义一个人类Person:
5.1.1定义一个方法sayHello(),可以向对方发出问 候语“hello,my name is XXX”
5.1.2有三个属性:名字、身高、体重 • 5.2定义一个PersonCreate类:
5.2.1创建两个对象,分别是zhangsan,33岁,1.73 ;lishi,44,1.74
5.2.2分别调用对象的sayHello()方法
package lll; public class lll { String name; double height; int weight; int age; public void sayhello() { System.out.println("hello,my name is " + name); System.out.println("my height is " + height + "米"); System.out.println("my weight is " + weight + "斤"); System.out.println("my age is " + age + "岁"); } } package wen; public class PersonCreate { public static void main(String[] args) { // TODO Auto-generated method stub Person a = new Person(); Person b = new Person(); a.name ="zhangsan"; a.age = 33; a.height = 1.73; a.weight = 120; b.name = "lishi"; b.age = 44; b.height = 1.74; b.weight = 140; a.sayhello(); b.sayhello(); } }
定义一个汽车类Vehicle,要求如下:[选做题]
1.属性包括:汽车品牌brand(String类型)、颜色color(String类型)和速度speed(double类型),并且所有属性为私有。
2.至少提供一个有参的构造方法(要求品牌和颜色可以初始化为任意值,但速度的初始值必须为0)。
3.为私有属性提供访问器方法。注意:汽车品牌一旦初始化之后不能修改。
4.定义一个一般方法run(),用打印语句描述汽车奔跑
的功能
5.定义测试类VehicleTest,在其main方法中创建一个品牌为“benz”、颜色为“black”的汽车
package lll; public class lll { private final String brand; private String color; private double speed; public Vehicle(String brand, String color) { super(); this.brand = brand; this.color = color; } public void run() { System.out.println("本汽车正在以"+this.speed+"迈的速度行驶"); } ) public String getColor() { return color; } public void setColor(String color) { this.color = color; } public double getSpeed() { return speed; } public void setSpeed(double speed) { this.speed = speed; } public String getBrand() { return brand; } } package JavaDemo; public class VeichleTest { public static void main(String[] args) { // TODO Auto-generated method stub Vehicle v1=new Vehicle("benz","black"); v1.setSpeed(60); v1.run(); } } package JavaDemo; public class VeichleTest { public static void main(String[] args) { // TODO Auto-generated method stub Vehicle v1=new Vehicle("benz","black"); v1.setSpeed(60); v1.run(); } }