Java-异常处理练习

1.建立exception包,编写TestException.java程序，主方法中有以下代码，确定其中可能出现的异常，进行捕获处理。

package Yichang;

public class Text {

    public static void main(String[] args) {
        for(int i=0;i<4;i++){
            int  k;
            switch(i){

        case 0:
        try{
        int zero=0;
        k=911/zero;

        }
        catch(ArithmeticException e){
            System.out.println("输入有误");
        }
        break;
        case 1:
        try{
        int  b[]=null;
        k = b[0];

        }catch(NullPointerException e)
        {
            System.out.println("空指针异常");
        }
        break;
                case 2:
        try{
        int c[]=new int[2];

        k=c[9];

        }catch(ArrayIndexOutOfBoundsException e)
        {
            System.out.println("索引超出异常");
        }
        break;
                case 3:
        try{
        char ch="abc".charAt(99);

        }catch(Exception e)
        {
            e.printStackTrace();
            System.out.println("收取字符超出");
        }
        break;
            }
        }

    }

}

结果：

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2.建立exception包，建立Bank类，类中有变量double  balance表示存款,Bank类的构造方法能增加存款，Bank类中有取款的发方法withDrawal(double dAmount),当取款的数额大于存款时,抛出InsufficientFundsException,取款数额为负数，抛出NagativeFundsException,如new Bank(100),表示存入银行100元，当用方法withdrawal(150)，withdrawal(-15)时会抛出自定义异常。

package Yichang;

public class InsufficientFundsException extends Exception {
    public String getMessage()
    {
        return "余额不足";
    }
}

package Yichang;

public class NagativeFundsException extends Exception {
 public String getMessage()
 {
     return "取款不能为负数";
 }
}

package Yichang;

public class Test01 {
    private double balance;

    public Test01(double balance) {
        super();
        this.balance = balance;
    }
    public void withDrawal(double dAmount)throws InsufficientFundsException,NagativeFundsException
    {
        if(dAmount>balance)
        {
            throw new InsufficientFundsException();
        }
        if(dAmount<0)
        {
            throw new NagativeFundsException();
        }
    }

    public static void main(String[] args){
        Test01 t=new Test01(100);
        try{
        t.withDrawal(150);
        }catch(Exception e){
            e.printStackTrace();
        }
        try{
            t.withDrawal(-10);
        }catch(Exception e){
            e.printStackTrace();
        }
    }
}

结果：