java第九周上机练习

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（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。

package heihei;

public class Point {
	int x;
	int y;
    public Point() {}
     
    public Point(int x0,int y0){
		 this.x=x0;
		 this.y=y0;
	}
 public void movePoint(int dx,int dy){
	 System.out.printf("移动前点的坐标(x:%d,y:%d)
",this.x,this.y);
	 System.out.printf("移动量为(x:%d,y:%d)
",dx,dy);
	 this.x +=dx;
	 this.y +=dy;
	 System.out.printf("移动后点的坐标(x:%d,y:%d)
",this.x,this.y);
 }
}

　　

package heihei;

public class text {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Point p1=new Point(1,2);
		Point p2=new Point(3,4);
		p1.movePoint(p2.x,p2.y);
	}

}

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

package haha;

public class Rectangle {
   double length;
   double width;
   
public Rectangle(double length,double width){
	this.length=length;
	this.width=width;
	}
public double getArea(double length,double width){
    return this.length * this.width;	
}
public double getPer(double length,double width){
	return 2 * (this.length+this.width);
}
public void showAll(double length,double width){
	System.out.printf("长方形的长为:%3.3f,宽为:%3.3f
",this.length,this.width);
	System.out.printf("长方形的面积为:%3.3f
",getArea(length,width));
	System.out.printf("长方形的周长为:%3.3f
",getPer(length,width));
}
}

　　

package haha;

public class test {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
        Rectangle rectangle=new Rectangle(3,4);
        rectangle.showAll(rectangle.length,rectangle.width);
	}

}

• 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 hehe;

public class Computer {
     private char color;
     private int cpu;
     
public Computer (){}
     
public Computer(char color, int cpu){
	this.color=color;
	this.cpu=cpu;
}
 
public int getCpu(){
	return cpu;
}

public char getColor(){
	return color;
}

public void setCpu(int cpu){
	this.cpu=cpu;
}

public void setColor(char color){
	this.color=color;
}

public void showComputer(){
	System.out.printf("笔记本电脑颜色:%c	 CPU:%d
",getColor(),getCpu());
   }
}

　　

package hehe;

public class test {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
       Computer computer=new Computer();
       computer.showComputer();
       
       Computer computer2=new Computer('红',0722);
       computer2.showComputer();
	}
}

6、定义两个类，描述如下： [必做题]
• 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、年龄
• 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 xixi;

public class Person {
   private String name=null;
   private double hight;
   private double weight;
   
public Person(String name,double hight,double weight){
	this.name=name;
	this.hight=hight;
	this.weight=weight;
}

public String getName(){
	return name;
}

public double getHight(){
	return hight;
}
 
public double getWeight(){
	return weight;
}

public void setName(String name){
	this.name=name;
}

public void setHight(double hight){
	this.hight=hight;
}

public void setWeight(double weight){
	this.weight=weight;
}

public void sayHello(){
	System.out.printf("hello,my name is %s!
", name);
}
}

　　

package xixi;

public class test {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
     Person person1=new Person("zhangsqsan",33,1.73);
     Person person2=new Person("lisi",44,1.74);
     person1.sayHello();
     person2.sayHello();
	}

}