首页 > 代码库 > 异常处理
异常处理
import java.util.*;
public class ATM1 {
@SuppressWarnings("resource")
public static void main(String[] args) {
Scanner in=new Scanner(System.in);
ATM atm=new ATM();
int choose=0,num=0;
String pw="";
next:while(true){
System.out.println("是否进入账户（0否1是）：");
int kk=in.nextInt();
if(kk==0) break;
else if(kk!=1){
System.out.println("输入错误！");
continue;
}
System.out.println("输入账户密码：");
pw=in.next();
if(atm.ifPass(pw)){
while(true){
showFace();
choose=in.nextInt();
switch(choose){
case 1:
System.out.println("输入存款金额：");
num=in.nextInt();
atm.save(num);
System.out.println("存款成功！");
System.out.println("当前余额："+atm.getRest()+"元");
break;
case 2:
System.out.println("请选择：");
int a[]={100,500,1000,1500,2000,5000};
for(int i=0;i<a.length;i++)
System.out.println((i+1)+"."+a[i]+"元");
System.out.println("7.其他");
int ch=in.nextInt();
if(ch>=1&&ch<=6){
if(atm.withdraw(a[ch-1]))
System.out.println("取款成功！");
else
System.out.println("余额不足！");
}
else if(ch==7){
System.out.println("请输入取款金额：");
num=in.nextInt();
if(atm.withdraw(num))
System.out.println("取款成功！");
else
System.out.println("余额不足！");
}
else
System.out.println("输入有误！");
System.out.println("当前余额："+atm.getRest()+"元");
break;
case 3:
System.out.println("账户号：");
String s=in.next();
System.out.println("转账金额：");
int i=in.nextInt();
if(atm.transfer(s, i))
System.out.println("转账成功！");
else
System.out.println("转账失败！");
System.out.println("当前余额："+atm.getRest()+"元");
break;
case 4:
System.out.println("输入六位数密码：");
String p=in.next();
atm.setPassword(p);
break;
case 5:
System.out.println("当前余额："+atm.getRest()+"元");
break;
default:
continue next;
}
}
}
else
System.out.println("密码错误！");
}
}
//显示菜单方法
public static void showFace(){
System.out.println("********************");
System.out.println(" 1.存款：");
System.out.println(" 2.取款：");
System.out.println(" 3.转账汇款：");
System.out.println(" 4.修改密码：");
System.out.println(" 5.查询余额：");
System.out.println(" 6.退卡：");
System.out.println("********************");
System.out.println("请选择：");
}
}
class PersonalAccount{
private String passWord="123456";
@SuppressWarnings("unused")
private String number;//银行卡号
private int money=0;
public int getMoney(){return money;}
public void setPw(String s){passWord=s;}
public void addMoney(int x){money+=x;}
public void minusMoney(int x){money-=x;}
public boolean whetherPwTrue(String s){
if(s.equals(passWord))
return true;
else return false;
}
}
abstract class PATM{
public abstract boolean withdraw(int x);
public abstract void save(int x);
public abstract boolean transfer(String s,int x);
public abstract boolean ifPass(String s);
public abstract int getRest();
public abstract void setPassword(String s);//设置密码
}
class ATM extends PATM{
private String numbers[]={"3235635","3256894",
"3265894","6589458"};
private PersonalAccount account=new PersonalAccount();
public boolean withdraw(int x) {
if(x>account.getMoney())
return false;
else{
account.minusMoney(x);
return true;
}
}
public void save(int x) {
account.addMoney(x);
}
public boolean transfer(String s, int x) {
boolean flag=false;
for(int i=0;i<numbers.length;i++)
if(s.equals(numbers[i])) flag=true;
if(x>account.getMoney()) flag=false;
if(x<=account.getMoney()&&flag) account.minusMoney(x);;
return flag;
}
public boolean ifPass(String s) {
return account.whetherPwTrue(s);
}
public int getRest() {
return account.getMoney();
}
public void setPassword(String s) {
account.setPw(s);
}
}
//判断数字并捕获可能出现的三种异常。
public class MyException{
public static void check(String str1)
throws NullPointerException{
//方法头抛出空指针异常
if(str1.length()>2){
str1=null;
}
}
System.out.println(str1.length());
//空字符串的长度
}
char ch;
for (int i=0;i<str1.length();i++){
String str1;
ch=str1.charAt(i);
if(!Character.isDigit(ch))
//判断参数中字符是否为数字
throw new NumberFormatException(); //方法中抛出数字格式异常
}
}
public static void main(String args[])
throws Exception{
//抛出异常给系统处理
int num;
try{
check(args[0]);
num=Integer.parseInt(args[0]);
if (num>60)
System.out.println("成绩为："+num+" 及格");
else
System.out.println("成绩为："+num+" 不及格");
}
catch(NullPointerException e){
System.out.println("空指针异常："+e.toString());
}
catch(NumberFormatException ex){
System.out.println("输入的参数不是数值类型");
}
catch(Exception e){
System.out.println("命令行中没有提供参数");
}
}
}
//求阶乘并捕获可能出现的三种异常
public class MyException{
public static double multi(int n){
if(n<0)
throw new IllegalArgumentException("求负数阶乘异常");
double s=1;
for(int i=1;i<=n;i++)
s=s*i;
return s;
}
public static void main(String[] args){
try{
}
int m=Integer.parseInt(arg[0]);
System.out.println(m+"!="+multi(m));
//调用方法multi求阶乘。
}
catch (ArrayIndexOutOfBoundsException e){
System.out.println("命令行中没提供参数！");
}
catch (NumberFormatException e){
System.out.println("应输入一个整数！");
}
catch (IllegalArgumentException e){
System.out.println("出现的异常是："+e.toString());
}
finally{
System.out.println("程序运行结束！");
}
}
}
异常处理