请定义一个交通工具(Vehicle)类
其中有属性:
速度speed
体积size
方法移动move()
设置速度setSpeed(int speed)
加速speedUp()
减速speedDown()
最后在测试类Vehicle中的main() 中实例化一个交通工具对象,并通过方法给它初始化speed,size的值并且打印出来,另外调用加速减速的方法对速度进行改变
搭建大体框架:
/*** @author LBJ* @version V1.0* @Package PACKAGE_NAME* @date 2021/1/28 17:38* @Copyright 公司*//*
请定义一个交通工具(Vehicle)类其中有属性:速度speed体积size方法移动move()设置速度setSpeed(int speed)加速speedUp()减速speedDown()最后在测试类Vehicle中的main() 中实例化一个交通工具对象,并通过方法给它初始化speed,size的值并且打印出来,另外调用加速减速的方法对速度进行改变*/
public class Test01{public static void main(String[] args) {//通过无参数构造方法创建对象Vehicle vehicle = new Vehicle();vehicle.setSpeed(100);vehicle.setSize(20);System.out.println("speed:"+vehicle.getSpeed());System.out.println("size:"+vehicle.getSize());//调用加速方法vehicle.speedUp();System.out.println(vehicle.getSpeed());//调用减速方法vehicle.speedDown();System.out.println(vehicle.getSpeed());//通过有参数构造方法创建对象//Vehicle vehicle1 = new Vehicle(100, 20);}
}class Vehicle {private int speed;private int size;public Vehicle(){}public Vehicle(int speed,int size){this.speed=speed;this.size=size;}public int getSpeed() {return speed;}public void setSpeed(int speed) {this.speed = speed;}public int getSize() {return size;}public void setSize(int size) {this.size = size;}//移动方法public void move(){}//加速方法public void speedUp(){}//减速方法噶public void speedDown(){}
}
结果:两个速度值并没有因为调用方法而改变
进阶调整后的代码:
/*** @author LBJ* @version V1.0* @Package PACKAGE_NAME* @date 2021/1/28 17:38* @Copyright 公司*//*
请定义一个交通工具(Vehicle)类其中有属性:速度speed体积size方法移动move()设置速度setSpeed(int speed)加速speedUp()减速speedDown()最后在测试类Vehicle中的main() 中实例化一个交通工具对象,并通过方法给它初始化speed,size的值并且打印出来,另外调用加速减速的方法对速度进行改变*/
public class Test01{public static void main(String[] args) {//通过无参数构造方法创建对象Vehicle vehicle = new Vehicle();vehicle.setSpeed(100);vehicle.setSize(20);System.out.println("speed:"+vehicle.getSpeed());System.out.println("size:"+vehicle.getSize());//调用移动方法vehicle.move();//调用加速方法vehicle.speedUp(10);System.out.println("speed:"+vehicle.getSpeed());//调用减速方法vehicle.speedDown(10);System.out.println("speed:"+vehicle.getSpeed());//通过有参数构造方法创建对象//Vehicle vehicle1 = new Vehicle(100, 20);}
}class Vehicle {private int speed;private int size;public Vehicle(){}public Vehicle(int speed,int size){this.speed=speed;this.size=size;}public int getSpeed() {return speed;}public void setSpeed(int speed) {this.speed = speed;}public int getSize() {return size;}public void setSize(int size) {this.size = size;}//移动方法public void move(){System.out.println("公交车开始启动");}//加速方法public void speedUp(int addSpeed){//this.getSpeed()是原来的基础速度,addSpeed是后来增加的速度this.setSpeed(this.getSpeed() + addSpeed);}//减速方法噶public void speedDown(int subSpeed){if(subSpeed<this.getSpeed()){this.setSpeed(this.getSpeed() - subSpeed);}else {System.out.println("请输入比当前速度小的值");}}
}
运行结果:
编写简单的计算器
定义名为Number 的类,其中有两个整型数据成员n1和n2应声明为私有
编写构造方法赋予 n1 和 n2 的初始值
再为该类定义 加、减、乘、除等公有实例方法
分别对两个成员变量执行加减乘除的运算
大体结构:
/*** @author LBJ* @version V1.0* @Package PACKAGE_NAME* @date 2021/1/28 17:38* @Copyright 公司*//*
编写简单的计算器定义名为Number 的类,其中有两个整型数据成员n1和n2应声明为私有编写构造方法赋予 n1 和 n2 的初始值再为该类定义 加、减、乘、除等公有实例方法分别对两个成员变量执行加减乘除的运算*/
public class Test01{public static void main(String[] args) {Number number = new Number(1,2);number.addition();number.subtration();number.multiplication();number.division();}
}class Number{private int n1;private int n2;public Number(){}public Number(int n1,int n2){this.n1=n1;this.n2=n2;}public int getN1() {return n1;}public void setN1(int n1) {this.n1 = n1;}public int getN2() {return n2;}public void setN2(int n2) {this.n2 = n2;}public void addition(){System.out.println(this.getN1()+"+"+this.getN2()+"="+(this.getN1()+this.getN2()));}public void subtration(){System.out.println(this.getN1()+"-"+this.getN2()+"="+(this.getN1()-this.getN2()));}public void multiplication(){System.out.println(this.getN1()+"*"+this.getN2()+"="+(this.getN1()*this.getN2()));}public void division(){System.out.println(this.getN1()+"/"+this.getN2()+"="+(this.getN1()/this.getN2()));}
}
测试结果:之所以1/2=0是因为int类型的取整
添加安全控制:
/*** @author LBJ* @version V1.0* @Package PACKAGE_NAME* @date 2021/1/28 17:38* @Copyright 公司*//*
编写简单的计算器定义名为Number 的类,其中有两个整型数据成员n1和n2应声明为私有编写构造方法赋予 n1 和 n2 的初始值再为该类定义 加、减、乘、除等公有实例方法分别对两个成员变量执行加减乘除的运算*/
public class Test01{public static void main(String[] args) {Number number = new Number(1,0);number.addition();number.subtration();number.multiplication();number.division();}
}class Number{private int n1;private int n2;public Number(){}public Number(int n1,int n2){this.n1=n1;this.n2=n2;}public int getN1() {return n1;}public void setN1(int n1) {this.n1 = n1;}public int getN2() {return n2;}public void setN2(int n2) {this.n2 = n2;}public void addition(){System.out.println(this.getN1()+"+"+this.getN2()+"="+(this.getN1()+this.getN2()));}public void subtration(){System.out.println(this.getN1()+"-"+this.getN2()+"="+(this.getN1()-this.getN2()));}public void multiplication(){System.out.println(this.getN1()+"*"+this.getN2()+"="+(this.getN1()*this.getN2()));}public void division(){if(this.getN2()==0){System.out.println("除数不能为0");return;}System.out.println(this.getN1()+"/"+this.getN2()+"="+(this.getN1()/this.getN2()));}
}
测试结果: