继承的代码解释（前）

//分析以下程序存在什么问题？代码臃肿。代码没有得到重复利用。
public class ExtendsTest01 {
    public static void main(String[] args) {
        //创建普通账户
        Account act=new Account();
        act.setActno("111111");
        act.setBalance(10000);
        System.out.println(act.getActno()+"，余额"+act.getBalance());

        //创建信用账户
        CreditAccount ca=new CreditAccount();
        ca.setActno("222222");
        ca.setBalance(-10000);
        ca.setCredit(0.99);
        System.out.println(ca.getActno()+"，余额"+ca.getBalance()+"，信誉度"+ca.getCredit());
    }
}




//银行账户类
//账户的属性：账号、 余额
class Account{
    //属性
    private String actno;
    private double balance;

    //构造方法
    public Account(){

    }
    public Account(String actno,double balance){
        this.actno=actno;
        this.balance=balance;
    }

    //setter and getteer方法
    public void setActno(String actno){
        this.actno=actno;
    }
    public String getActno(){
        return actno;
    }
    public void setBalance(double balance){
        this.balance=balance;
    }
    public double getBalance(){
        return balance;
    }
}

//其它类型的账户：信用卡账户
//账号、余额、信誉度
class CreditAccount{
    //属性
    private String actno;
    private double balance;
    private double credit;

    //构造方法
    public CreditAccount(){

    }

    //setter and getter 方法
    public void setActno(String actno){
        this.actno=actno;
    }
    public String getActno(){
        return actno;
    }
    public void setBalance(double balance){
        this.balance=balance;
    }
    public double getBalance(){
        return balance;
    }
    public void setCredit(double credit){
        this.credit=credit;
    }
    public double getCredit(){
        return credit;
    }

}