07-异常处理

package 测试;
import javax.swing.*;
class AboutException {
   public static void main(String[] a) 
   {
      int i=1, j=0, k;
      k=i/j;
	try
	{
		k = i/j;    // Causes division-by-zero exception
		            //throw new Exception("Hello.Exception!");
	}
	catch ( ArithmeticException e)
	{
		System.out.println("被0除.  "+ e.getMessage());
	}
	catch (Exception e)
	{
		if (e instanceof ArithmeticException)
			System.out.println("被0除");
		else
		{  
			System.out.println(e.getMessage());
			
		}
	}
	finally
     {
     		JOptionPane.showConfirmDialog(null,"OK");
     }
  }
}

　　

ArrayIndexOutOfBoundsException/内层try-catch

发生ArithmeticException

ArrayIndexOutOfBoundsException/外层try-catch

 

 

当try不出错时，只运行finally

 

finally语句块不一定会执行，当Try语句中throw一个错误时fin被catch语句截获，并在catch语句中有exit（0）时，finally语句不会被执行。

 

 

 

package 考试成绩;
import java.util.Scanner;
// 陈天时 20163591 信1605-3
public class KaoShiChengJi 
{
	public static void main(String[] args)
    {
		@SuppressWarnings("resource")
		Scanner input=new Scanner(System.in);
        for(;;)//无限循环
        {
        	System.out.println("请输入一门考试的成绩：");
    		String I=input.next();
    		int i=Integer.parseInt(I);
            try
            {

                if(i>0&&i<60)
                {
                	System.out.println("不及格");
                	continue;//跳出循环
                }
                else if(i>=60&&i<70)
                {
                	System.out.println("及格");
                	continue;
                }
                else if(i>=70&&i<80)
                {
                	System.out.println("中");
                	continue;
                }
                else if(i>=80&&i<90)
                {
                	System.out.println("良");
                	continue;
                }
                else if(i>=90&&i<=100)
                {
                	System.out.println("优");
                    continue;
                }
                else 
                {
                	System.out.println("您输入的成绩超出范围，请重新输入!");
                }
            }
            catch(NumberFormatException e)
            {
            	System.out.println("您输入的成绩超出范围，请重新输入!");
            }
            continue;
        }
    }
}