第九周上机作业
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(int
x0,y0),以及一个movePoint(int dx,int dy)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。[
必作题]
package chap; public class test { private int x; private int y; public Point() { } public Point(int x0, int y0) { x = x0; y = y0; } public void movePoint(int dx, int dy) { x = dx; y = dy; } public int getX() { return x; } public int getY() { return y; } }
package chap; public class Main { public static void main(String[] args) { Point p1 = new Point(3, 4); Point p2 = new Point(5, 6); p1.movePoint(7, 8); p2.movePoint(9, 10); System.out.println("p1坐标为 x=" + p1.getX() + " y=" + p1.getY()); System.out.println("p2坐标为 x=" + p2.getX() + " y=" + p2.getY()); } }
2、定义一个矩形类Rectangle:(知识点:对象的
创建和使用)[必做题]
• 2.1 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。
• 2.2 有2个属性:长length、宽width
• 2.3 通过构造方法Rectangle(int width, int length),
分别给两个属性赋值
• 2.4 创建一个Rectangle对象,并输出相关信息
import java.util.Scanner; class text{ public static void main(String[] args) { Rectangle r=new Rectangle(); System.out.println("请输入矩形长度"); Scanner sc=new Scanner(System.in); int length = sc.nextInt(); r.setLength(length); System.out.println("请输入矩形宽度"); int width = sc.nextInt(); r.setWidth(width); r.getAll(); r.getArea(); r.getPer(); } }
public class Rectangle { private int length; private int width; public Rectangle() { } public Rectangle(int length, int width) { this.length = length; this.width = width; } public int getLength(int i) { return length; } public int getWidth() { return width; } public void setLength(int length) { this.length = length; } public void setWidth(int width) { this.width = width; } public void getArea(){ System.out.println("面积为;"+width*length); } public void getPer(){ System.out.println("周长为;"+(width+length)*2); } public void getAll(){ System.out.println("长度为"+length+"宽度为"+width+"面积为"+width*length+"周长为"+(width+length)*2); } }
• 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]
• 3.1 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;
• 3.2 输出笔记本信息的方法
• 3.3 然后编写一个测试类,测试笔记本类的各个
方法。
package chap; public class Computer { char color; int cpu; public void getDate() { } public void getDate(char color, int cpu) { this.color = color; this.cpu = cpu; } void showAll() { System.out.println("颜色为" + color + ",cpu型号为" + cpu); } }
package chap; public class text { public static void main(String[] args) { // TODO Auto-generated method stub Computer cp = new Computer(); cp.getDate('红', 211); cp.showAll(); } }
• 6、定义两个类,描述如下:
• 6.1定义一个人类Person:
• 6.1.1定义一个方法sayHello(),可以向对方发出问候语“hello,my name is XXX”
• 6.1.2有三个属性:名字、身高、体重
• 6.1.3通过构造方法,分别给三个属性赋值
• 6.2定义一个Constructor类:
• 6.2.1创建两个对象,分别是zhangsan,33岁,1.73;lishi,44,1.74
• 6.2.2分别调用对象的sayHello()方法。
package chap; public class Person { private String name; private double height; private int age; public void sayHello() { System.out.println("Hello, my name is " + name); } public Person(double height, int age, String name) { this.name = name; this.height = height; this.age = age; } }
package chap; public class Constructor { public static void main(String[] args) { Person zs = new Person(1.73, 33, "zhangsan"); Person ls = new Person(1.74, 44, "lishi"); zs.sayHello(); ls.sayHello(); } }