java 语言程序设计-李尊朝 第6章 类和对象 练习答案

public class Account 
	 {
	    String account;
	    String name;
	    String address;
	    double balance;
	    static double minBalance=50;
	    public Account() 
	     {
	    	account="XXX";
	    	name="Jone";
	    	address="YYY";
	    	balance=0;
	     }
	    public Account(String account,String name,String address,double balance)
	     {
	    	this.account=account;
	    	this.address=address;
	    	this.name=name;
	    	this.balance=balance;
	     }
	    	
	   public void deposit(double cash)
	    {
	   	   System.out.println("您帐户原有余额： "+balance);
	   	   System.out.println("现存入： "+cash);
	   	   balance+=cash;
	   	   System.out.println("最终余额： "+balance);
	   	}
	   	
	   public void withdraw(double cash)
	    {
	   	  double temp=balance-cash;
	   	  if(temp<minBalance) 
	          System.out.println("至少保留余额："+minBalance);
	   	  else  
	          balance=temp;
	   	}
	   	
	   public void query()
	   {
	   	  System.out.println("您的余额是： "+balance);
	   	}	
	    
	  public static void  main(String[] args)
	  {
	  	 Account Jame=new Account("111222","Jame","xi'an jiaotong University",200.00);
	  	 Jame.deposit(300.5);
	  	 Jame.withdraw(200);
	  	 Jame.withdraw(300);
	  	 Jame.query();
	  	}
	}

习题5 举例说明类变量和实例变量的区别

	class Student1
	 {
	  String name;              //实例成员变量
	  String address;           //实例成员变量
	  static int count=0;      //类成员变量
	  public Student1(String m, String a )
	  { name=m;
	    address=a;
	    count=count+1;
	  }
	  public static void main(String args[])
	 {
	   Student1 p1=new Student1("李明","西安市未央区");
	   Student1 p2=new Student1("张敏", "上海市闽行区");
	   System.out.println(p1.name+" "+p1.address+" "+p1.count);
	   Student1.count=Student1.count+1;
	   System.out.println(p2.name+" "+p2.address+" "+p2.count);
	   p1.count=p1.count-1;
	   System.out.println(p2.name+" "+p2.address+" "+p2.count);
	  }
	}

习题8 编写程序,模拟银行帐户功能.要求如下

      属性:帐号\储户姓名、地址、存款余额、最小余额

      方法：存款、取款、查询

      根据用户操作显示帐户相关信息。如存款操作后，显示储户原有余额、今日存款额、最终存款余额 ;

      取款时，若最后佘额小于最小余额，拒绝取款，并显示“至少保留余额:xxx

public class Account 
	 {
	    String account;
	    String name;
	    String address;
	    double balance;
	    static double minBalance=50;
	    public Account() 
	     {
	    	account="XXX";
	    	name="Jone";
	    	address="YYY";
	    	balance=0;
	     }
	    public Account(String account,String name,String address,double balance)
	     {
	    	this.account=account;
	    	this.address=address;
	    	this.name=name;
	    	this.balance=balance;
	     }
	    	
	   public void deposit(double cash)
	    {
	   	   System.out.println("您帐户原有余额： "+balance);
	   	   System.out.println("现存入： "+cash);
	   	   balance+=cash;
	   	   System.out.println("最终余额： "+balance);
	   	}
	   	
	   public void withdraw(double cash)
	    {
	   	  double temp=balance-cash;
	   	  if(temp<minBalance) 
	          System.out.println("至少保留余额："+minBalance);
	   	  else  
	          balance=temp;
	   	}
	   	
	   public void query()
	   {
	   	  System.out.println("您的余额是： "+balance);
	   	}	
	    
	  public static void  main(String[] args)
	  {
	  	 Account Jame=new Account("111222","Jame","xi'an jiaotong University",200.00);
	  	 Jame.deposit(300.5);
	  	 Jame.withdraw(200);
	  	 Jame.withdraw(300);
	  	 Jame.query();
	  	}
	}