Javase—继承习题

/** * 【练习题】1.继承：定义一个名为Vehicles（交通工具）的基类，该类中应包含String类型的成员属性brand（商标）和color（颜色），还应包含成员方法run（行驶，在控制台显示“我已经开动了”）和showInfo（显示信息，在控制台显示商标和颜色），并编写构造方法初始化其成员属性。编写Car（小汽车）类继承于Vehicles类，增加int型成员属性seats（座位），还应增加成员方法showCar（在控制台显示小汽车的信息），并编写构造方法。 编写Truck（卡车）类继承于Vehicles类，增加float型成员属性load（载重），还应增加成员方法showTruck（在控制台显示卡车的信息），并编写构造方法。 在main方法中测试以上各类。 */package com.Oracle.oop3;public class Car01 extends Vehicles {int seats;public int getSeats() {return seats;}public void setSeats(int seats) {this.seats = seats;}public void showCar() {showInfo();System.out.println("seats:"+seats);}public Car01(String brand,String color,int seats) {super();this.brand=brand;this.color=color;this.seats = seats;}}package com.Oracle.oop3;public class Truck extends Vehicles {float load;public float getLoad() {return load;}public void setLoad(float load) {this.load = load;}public void showTruck() {showInfo();System.out.println("load:"+load);}public Truck(String brand,String color,float load) {super();this.brand=brand;this.color=color;this.load = load;}}package com.Oracle.oop3;public class Inherit01 {public static void main(String[] args) {Car01 c=new Car01("Audi","blue",6);c.showCar();c.run();c.showInfo();Truck t=new Truck("奔腾","brown",15.9f);t.showTruck();t.run();}}

/** * 【练习题】2.继承：编写一个类Calculate1，实现加、减两种运算，然后，编写另一个派生类Calculate2，实现乘、除两种运算。 */package com.Oracle.oop3;public class Calculate1 {public int plus(int a,int b) {return a+b;}public int minus(int a,int b) {return a-b;}}package com.Oracle.oop3;public class Calculate2 extends Calculate1{public int multiply(int a,int b) {return a*b;}public double divide(double a,double b) {return a/b;}}package com.Oracle.oop3;public class Inherit02 {public static void main(String[] args) {Calculate2 c=new Calculate2();System.out.println(c.plus(9, 7));System.out.println(c.minus(17, 21));System.out.println(c.multiply(7, 17));System.out.println(c.divide(86, 3));}}

/** * 【练习题】3.包、继承、构造函数编写一个控制台应用程序，完成下列功能，并回答提出的问题。       1) 创建一个类A，在构造函数中输出“A”，再创建一个类B，在构造函数中输出“B”。       2) 从A继承一个名为C的新类，并在C内创建一个成员变量B。不要为C创建构造函数。      3) 在Main方法中创建类C的一个对象，写出运行程序后输出的结果。       4) 如果在C中也创建一个构造函数输出“C”，整个程序运行的结果又是什么？ */package com.Oracle.oop3;public class A {public A(){System.out.println("A");}}package com.Oracle.oop3;public class B {public B() {System.out.println("B");}}package com.Oracle.oop3;public class C extends A {B b;public B getB() {return b;}public void setB(B b) {this.b = b;}public C() {System.out.println("C");}}package com.Oracle.oop3;public class Inherit03 {public static void main(String[] args) {C c=new C();c.getB();}}

/** * 【练习题】4.继承：建立三个类：居民、成人、官员。居民包含身份证号、姓名、出生日期，而成人继承自居民，多包含学历、职业两项数据；官员则继承自成人，多包含党派、职务两项数据。要求每个类的字段都以属性的方式对外提供数据输入输出的功能。 */package com.Oracle.oop3;public class Resident {long id;String name;String birth;public long getId() {return id;}public void setId(long id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getBirth() {return birth;}public void setBirth(String birth) {this.birth = birth;}}package com.Oracle.oop3;public class Adult extends Resident {String diplomas;String occupation;public String getDiplomas() {return diplomas;}public void setDiplomas(String diplomas) {this.diplomas = diplomas;}public String getOccupation() {return occupation;}public void setOccupation(String occupation) {this.occupation = occupation;}}package com.Oracle.oop3;public class Officer extends Adult{String groups;String duty;public String getGroups() {return groups;}public void setGroups(String groups) {this.groups = groups;}public String getDuty() {return duty;}public void setDuty(String duty) {this.duty = duty;}}package com.Oracle.oop3;public class Inherit04 {public static void main(String[] args) {Officer o=new Officer();o.setId(1000);o.setName("习大大");o.setBirth("1960年6月6日");o.setDiplomas("博士后");o.setOccupation("主席");o.setGroups("共产党");o.setDuty("管理中国");System.out.println("id: "+o.getId());System.out.println("name: "+o.getName());System.out.println("birth: "+o.getBirth());System.out.println("diplomas: "+o.getDiplomas());System.out.println("occupation: "+o.getOccupation());System.out.println("groups: "+o.getGroups());System.out.println("duty: "+o.getDuty());}}

/** * 【练习题】5.覆盖、继承建立一个汽车Auto类，包括轮胎个数，汽车颜色，车身重量、速度等成员变量。并通过不同的构造方法创建实例。至少要求： 汽车能够加速，减速，停车。 再定义一个小汽车类Car，继承Auto，并添加空调、CD等成员变量，覆盖加速，减速的方法 */package com.Oracle.oop3;public class Auto {int tyre=4;String color;int weight=100;int speed=60;public int getTyre() {return tyre;}public void setTyre(int tyre) {this.tyre = tyre;}public String getColor() {return color;}public void setColor(String color) {this.color = color;}public int getWeight() {return weight;}public void setWeight(int weight) {this.weight = weight;}public int getSpeed() {return speed;}public void setSpeed(int speed) {this.speed = speed;}public Auto(int tyre, String color, int weight, int speed) {super();this.tyre = tyre;this.color = color;this.weight = weight;this.speed = speed;}public Auto(int tyre, String color, int weight) {super();this.tyre = tyre;this.color = color;this.weight = weight;}public Auto(String color, int weight, int speed) {super();this.color = color;this.weight = weight;this.speed = speed;}public Auto() {}public void speedUp(int speed) {this.speed+=speed;System.out.println("您的汽车要加速："+speed+"现在的速度为："+this.speed);}public void speedDown(int speed) {this.speed-=speed;System.out.println("您的汽车要减速："+speed+"现在的速度为："+this.speed);}public void speedStop() {this.speed=0;System.out.println("您要停车，速度已降为0");}}package com.Oracle.oop3;public class Car05 extends Auto{boolean air;String cd;public boolean isAir() {return air;}public void setAir(boolean air) {this.air = air;}public String getCd() {return cd;}public void setCd(String cd) {this.cd = cd;}public void speedUp(int speed) {this.speed+=speed;System.out.println("您的小汽车已经加速了："+speed+"现在的速度为："+this.speed);}public void speedDown(int speed) {this.speed-=speed;System.out.println("您的汽车要减速："+speed+"现在的速度为："+this.speed);}public Car05() {}}package com.Oracle.oop3;public class Inherit05 {public static void main(String[] args) {@SuppressWarnings("unused")Auto a=new Auto("blue",100,65);Car05 c=new Car05();c.speedUp(15);c.speedDown(23);c.speedStop();}}

/** * 写一个用户程序测试Account类。在用户程序中，创建一个账号为1122、余额为20000、年利率4.5%的Account对象。  使用withdraw方法提款30000元，并打印余额。  再使用withdraw方法提款2500元，使用deposit方法存款3000元，然后打印余额和月利率。 * 要求：写一个用户程序测试CheckAccount类。在用户程序中，创建一个账号为1122、余额为20000、年利率4.5%，可透支限额为5000元的CheckAccount对象。使用withdraw方法提款5000元，并打印账户余额和可透支额。再使用withdraw方法提款18000元，并打印账户余额和可透支额。再使用withdraw方法提款3000元，并打印账户余额和可透支额。 *//** * 2、创建Account类的一个子类CheckAccount代表可透支的账户，该账户中定义一个属性overdraft代表可透支限额。 * 在CheckAccount类中重写withdraw方法，其算法如下：如果（取款金额<账户余额），可直接取款如果（取款金额>账户余额），计算需要透支的额度。判断可透支额overdraft是否足够支付本次透支需要，如果可以，将账户余额修改为0，冲减可透支金额如果不可以，提示用户超过可透支额的限额 */package com.Oracle.oop3;import com.Oracle.oop2.Account;public class CheckAccount extends Account{double overdraft=5000;//可透支金额public CheckAccount(int id, double balance, double annualInterestRate, double overdraft) {super(id, balance, annualInterestRate);this.overdraft=overdraft;// TODO Auto-generated constructor stub}public void display() {System.out.println("id:"+super.getId()+", balance:"+super.getBalance()+", annualInterestRate:"+super.getAnnualInterestRate()+", overdraft:"+this.overdraft);}public void displayBalanceAndOverdraft() {System.out.println("balance:"+super.getBalance()+", overdraft:"+this.overdraft);}public void withdraw (double amount) {if(super.getBalance()>=amount) {super.setBalance((super.getBalance()-amount));}else if(super.getBalance()+this.overdraft>=amount){super.setBalance(0);this.overdraft-=this.overdraft-(amount-super.getBalance());}else {System.out.println("超过可透支额的限额");}}}package com.Oracle.oop3;public class Inherit06 {public static void main(String[] args) {//Account a=new Account(1122,20000,0.045);//a.display();//a.withdraw(30000);//a.displayBalance();//a.withdraw(2500);//a.deposit(3000);//a.displayBalanceAndAnnualInterestRate();CheckAccount c=new CheckAccount(1122,20000,0.045,5000);c.display();c.withdraw(18000);c.displayBalanceAndOverdraft();c.withdraw(3000);c.displayBalanceAndOverdraft();}}

注：Account类在：OOP基础习题二