第八次·作业
1、定义一个点类Point,包含2个成员变量x、y分别表示x和y坐标,2个构造器Point()和Point(intx0,y0),以及一个movePoint(intdx,intdy)方法实现点的位置移动,创建两个Point对象p1、p2,分别调用movePoint方法后,打印p1和p2的坐标。
package wja;
public class Point {
int x;
int y;
public Point(int x0,int y0) {
super();
this.x=x0;
this.y=y0;
}
public Point() {
super();
}
public String movePoint(int dx,int dy) {
x=dx+x;
y=dy+y;
return("x为"+x+"y为"+y);
}
public static void main(String[] args) {
Point p1=new Point(1,8);
System.out.println(p1.movePoint(2,4));
Point p2=new Point(5,6);
System.out.println(p2.movePoint(2,5));
}
}
2.定义一个矩形类Rectangle:(知识点:对象的创建和使用)[必做题]
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。
有2个属性:长length、宽width
通过构造方法Rectangle(intwidth,intlength),分别给两个属性赋值
创建一个Rectangle对象,并输出相关信息
package wja;
public class Rectangle {
int length;
int width;
public int getArea(int length,int width) {
return length*width;
}
public int getPer(int length,int width) {
return (length+width)*2;
}
public void showAll() {
System.out.println("长方形的长是"+length+ "宽是"+width+ "周长是"+(length+width)*2+ "面积是"+length*width);
}
public Rectangle(int length,int width) {
super();
this.length=length;
this.width=width;
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Rectangle r=new Rectangle(6,9);
r.showAll();
}
}
3.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]
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;
输出笔记本信息的方法
然后编写一个测试类,测试笔记本类的各个方法。
package shg;
public class Ben {
public static void main(String[] args) {
// TODO Auto-generated method stub
Computer c1=new Computer('银',21);
c1.showComputer();
Computer c2=new Computer('白',32);
c2.showComputer();
}
}
class Computer {
private char color;
private int cpuNum;
public Computer() {
}
public Computer(char color,int cpuNum) {
this.color=color;
this.cpuNum=cpuNum;
}
public char getColor() {
return color;
}
public void setColor(char color) {
this.color=color;
}
public int getcpuNum() {
return cpuNum;
}
public void setcpuNum(int cpuNum) {
this.cpuNum=cpuNum;
}
public void showComputer() {
System.out.println("笔记本的颜色:"+getColor());
System.out.println("笔记本的CPU型号:"+getcpuNum());
}
}
5.定义两个类,描述如下:[必做题]
1.定义一个人类Person:
(1)定义一个方法sayHello(),可以向对方发出问候语“hello,mynameisXXX”
(2)有三个属性:名字、身高、体重
2.定义一个PersonCreate类:
(1)创建两个对象,分别是zhangsan,33岁,1.73;lishi,44,1.74
(2)分别调用对象的sayHello()方法。
package girl;
public class Person {
private String names;
private int age;
private double height;
public String getNames() {
return names;
}
public void setNames(String names) {
this.names = names;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public double getHeight() {
return height;
}
public void setHeight(double height) {
this.height = height;
}
public Person(String names, int age, double height) {
super();
this.names = names;
this.age = age;
this.height = height;
}
public void sayHello() {
System.out.println("hello,my name is"+" "+names);
System.out.println("年龄为"+age+"身高为"+height);
}
}
package girl;
public class Test {
public static void main(String[] args) {
// TODO Auto-generated method stub
Person a1=new Person("zhangsan",33,1.73);
a1.sayHello();
Person a2=new Person("lishi",44,1.74);
a2.sayHello();
}
}
7..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 girl;
public class Vehicle {
private String band;
private String color;
private double speed;
public String getBand() {
return band;
}
public String getColor() {
return color;
}
public double getSpeed() {
return speed;
}
public Vehicle(String band, String color, double speed) {
super();
this.band = band;
this.color = color;
this.speed = 23;
}
public void run() {
System.out.println(color+"色"+band+"品牌的汽车"+"以"+speed+"的速度在行驶");
}
}
package girl;
public class Test {
public static void main(String[] args) {
// TODO Auto-generated method stub
Vehicle a=new Vehicle("benz","black",23);
a.run();
}
}