实验二 面向对象程序设计

实现如下业务：
开户，存款100，查询余额，取款50，查询余额，取款200，查询余额
2.继承的实现
（1）按如下类图编写代码
[参考代码]
class Person {
String id;
String name;
String age;
public void sleep() {
System.out.println("I am Person,I am sleeping");
{
super(inkPrinterType);
}
void print(String txt)
{
System.out.println("I am Ink Printer");
System.out.println("Start to Print:"+txt);
}
}
class LasertPrinter extends Printer{
{
for(int i=0;i<ps.length;i++){
ps[i].eat();
ps[i].sleep();
}
}
从以上代码中体会多态现象。
4.抽象类的使用
编写以上类图所示类，并编写测试代码测试抽象类的使用
[参考代码]
abstract class Printer{
private String printerType;
}else{
System.out.println("withdraw:"+money+" erro. Because of not enough balance");
}
}else
{
System.out.println("Password Erro");
}
}
}
（2）编写测试类，完成如下（1）中类方法的测试
System.out.println("Start to Print:"+txt);
}
}
class LasertPrinter extends Printer{
LasertPrinter(String laserPrinterType)
{
super(laserPrinterType);
}
void print(String txt)
{
System.out.println("I am Lasert Printer");
System.out.println("Start to Print:"+txt);
}
}
编写测试类及main()方法，完成如下操作
A.创建Printer,InkPrinter,LaserPrinter类的对象。
B.设计并编写演示多态现象的代码
this.balance-=money;
System.out.println("withdraw:"+money+" ok, Operator:"+operator );
System.out.println("Current Account Balance:"+this.balance);
System.out.println("Save Account change to database");
{
if(oldPassword==this.password)
{
System.out.println("Password OK");
this.password=newPassword;
System.out.println("Change Passord OK");
}else
{
System.out.println("Password Erro");
}
}
public void deposit(int money,String operator)
{
this.balance+=money;
System.out.println("add balance OK.Operator:"+operator);
System.out.println("Save Account change to database");
}
}
class Teacher extends Person {
String tid;
public void tech() {
System.out.println("I am Student,I am taching");
}
}
（2）编写测试类并创建main()方法，完成如下操作
A．分别创建Person、Student、Teacher对象，完成属性和每个方法的调用测试
Printer(String printerType){
this.printerType=printerType;
}
abstract void print(String txt);
void showMyType(){
System.out.println("My Type is:"+printerType);
B．在Student和Teacher中完成eat()方法的重写
C．编写类型转化示例（向上类型转化、向下类型转化）
3.多态现象
在完成（2）中Student、Teacher类eat()方法重载后，在测试类中编写如下代码并在main()方法中调用
static void askAllToEat(Person[] ps)
System.out.println("Operator:"+operator);
System.out.println("Save Account info to Database");
}
public void queryBalance(String password)
{
if(password==this.password)
}
public void eat() {
System.out.println("I am Person,I am eating");
}
}
class Student extends Person {
String sno;
public void study() {
System.out.println("I am Student,I am studying");
LasertPrinter(String laserPrinterType)
{
super(laserPrinterType);
}
void print(String txt)
{
System.out.println("I am Lasert Printer");
System.out.println("Start to Print:"+txt);
private String password;
private int balance;
public BankAccount(String accountID,String password,String operator)
{
this.accountID=accountID;
this.password=password;
}
}
思考与练习：
（1）自行设计并编写代码演示面向对象的三大特性
（2）练习抽象类的使用
（3）练习接口的使用
5.接口的使用
编写以上类图的代码，并编写测试类测试接口的使用
[参考代码]
interface IScan{
void scan();
}
abstract class Printer{
private String printerType;
Printer(String printerType){
this.printerType=printerType;
2.掌握继承的编程方式和思想
3.理解多态现象
4.掌握抽象类和接口的使用
实验内容与步骤
1.封装的实现
（1）编写程序模拟个人银行账号类。考虑个人银行的特点，建立类模型（注意属性和方法的访问权限修饰符）
[参考代码]
public class BankAccount {
private String accountID;
this.balance=0;
System.out.println("Create a BankAccount");
System.out.println("AccountID:"+this.accountID);
System.out.println("Current Balance:"+this.balance);
{
System.out.println("Password OK");
System.out.println("Current Account Balance:"+this.balance);
}else
{
System.out.println("Password Erro");