实验10--java异常(答案)

实验六Java异常处理【实验目的】1）掌握Java异常的概念及工作机制2）掌握异常的分类3）掌握抛出异常语句的使用(throw)4）掌握抛出捕获处理异常语句的使用(try…catch…finally)5）掌握上抛异常语句的使用(throws)6）掌握创建自定义异常【实验环境】JDK1.6+Eclpise3.2【实验准备】1）复习课件中理论知识2）练习课堂所讲的例子【实验内容】1、编写一个应用程序，要求从键盘输入一个double型的圆的半径，计算并输出其面积。

测试当输入的数据不是double型数据（如字符串“abc”）会产生什么结果，怎样处理。

package SIX;import java.io.IOException;import java.io.InputStreamReader;import java.io.BufferedReader;public class CIRCLE {public static void main(String[] args) throws IOException { System.out.print("请输入半径: ");BufferedReader br = new BufferedReader(new InputStreamReader(System.in));try{System.out.println("圆的面积为："+computerArea(Double.parseDouble(br.readLine())));}catch(NumberFormatException e){System.out.println("您输入的不是数值，请重新输入");}}public static double computerArea(double r){r eturn Math.PI*r*r;}}2、计算两个正数之和，当任意一个数超出范围时，抛出自己定义的异常（NumberRangeException）。

import java.io.BufferedReader;import java.io.IOException;import java.io.InputStreamReader;public class shu {public static void main(String[] args) throws IOException{System.out.println("请输入两个正整数(回车分隔):");BufferedReader br=new BufferedReader(newInputStreamReader(System.in));int a=Integer.parseInt(br.readLine());int b=Integer.parseInt(br.readLine());try{System.out.println("计算结果(求和)为：" +compute(a, b));} catch (NumberRangeException e){e.printStackTrace();}}public static int compute(int a, int b) throws NumberRangeException{if( (a<0 || b<0)){throw new NumberRangeException("数字不在指定范围");}return (a+b);}}class NumberRangeException extends Exception {public NumberRangeException(String msg){super(msg);}}3、编写一个类实现银行帐户的概念，包括的属性有“帐号”、“储户姓名”、“地址”、“存款余额”、“最小余额”、“利率”、“存款日期”，包括的方法有“存款”、“取款”、“查询”、“计算利息”、“累加利息”等。

并创建“取款数目超过余额”这个异常，并在取款方法中抛出并处理这个异常。

public class bank{int ID;String name;String address;double balance;double min_balance;double rate;double interest;public int getID() {//获取账户return ID;}public void setID(int iD) {//设置账户ID = iD;}public String getName() {//获取储户名return name;}public void setName(String name) {//设置储户名 = name;}public String getAddress() {//获取储户地址return address;}public void setAddress(String address) {//设置储户地址this.address = address;}public double getBalance() {//获取余额return balance;}public void setBalance(double balance) {//设置余额this.balance = balance;}public double getMin_balance() {//获取最小余额return min_balance;}public void setMin_balance(double minBalance) {//设置最小余额min_balance = minBalance;}public double getRate() {//获取利率return rate;public void setRate(double rate) {//设置利率this.rate = rate;}public void savingMoney(double money){//存款this.balance=this.balance+money;}public void drawMoney(double money) throws MyException{//取款，发现异常时抛出异常并处理if(money>this.balance){throw (new MyException());}elsethis.balance=this.balance-money;}public double Interest(double interest){//计算利息interest=getRate()*getBalance();this.interest=interest;return interest;}public double addInterest(double money){//累加利息money=this.balance+this.interest;return money;}public void check(){int id;String Name;String Add;double Balance;id=getID();Name=getName();Add=getAddress();Balance=getBalance();System.out.println("账号:"+id);System.out.println("姓名:"+Name);System.out.println("地址:"+Add);System.out.println("账户余额:"+Balance+"元");}class MyException extends Exception{//自定义异常类String message;public MyException(){message="取款数目超过余额,请重新输入取款金额!";//System.out.println("请重新输入取款金额！");//Bank bank=new Bank();//bank.drawMoney(100000.0);}public String toString(){return message;}}Bank_check.java 文件import java.util.*;public class Bank_check{public static void main(String[] args){Bank b=new Bank();b.setID(123456);b.setName("laidazhang");b.setAddress("闽南科技学院");b.setBalance(100.0);b.check();System.out.println("-----------------存款操作：-------------------="); System.out.println("输入存款金额：");double x,y;Scanner reader= new Scanner(System.in);x=reader.nextDouble();System.out.println("存款后:");b.savingMoney(x);b.check();System.out.println("-----------------取款操作：-------------------="); System.out.println("输入取款金额：");Scanner reader1= new Scanner(System.in);y=reader1.nextDouble();System.out.println("取款后:");try{b.drawMoney(y);}catch(MyException e)//捕捉异常{System.out.println(e.toString());Scanner reader2= new Scanner(System.in);z=reader2.nextDouble();try{b.drawMoney(z);}catch(MyException e1){System.out.println(e.toString());}}finally{b.check();b.setRate(0.05);double interest=0;System.out.println("利息是："+b.Interest(interest)+"元");double money=0;System.out.println("本金加利息是："+b.addInterest(money)+"元");}}}【实验感想】。