多线程的并发一般不是程序员决定，而是由容器决定

 1 package TomTexts;
 2 
 3 
 4 class ExceptionExam7_1 extends Exception        //自定义异常类ExceptionExam7_1
 5 {
 6 private int show;
 7 ExceptionExam7_1 (int a)
 8 {
 9 show=a;
10 }
11 public String toString()
12 {
13 return "ExceptionExam7_1 <"+show+">";
14 }
15 }
16 public class TomTexts_37
17 {
18 static void caculate(int a) throws ExceptionExam7_1
19 {
20 System.out.println("对["+ a +"]已经进行过相应的操作");
21 if(a>100)
22 throw new ExceptionExam7_1 (a);
23 System.out.println("执行该算法正常退出！");
24 }
25 public static void main(String args[])
26 {
27 try
28 {
29 caculate(1);
30 caculate(1000);
31 }
32 catch (ExceptionExam7_1 e)
33 {
34 System.out.println("捕获了异常" + e);
35 }
36 }
37 }