自定义异常类：
public class ExtendsException extends Exception {
private static final long serialVersionUID = 1L;
public ExtendsException(String msg)
{
super(msg);
}
}入口类：
public class ExceptionTest {
public static void main(String args[])
{
/*
* 段落级的异常*/
int a=4,b=0;
try
{
if(b==0)
throw new ExtendsException("自定义异常");
else
System.out.println(a+"/"+b+"="+a/b);
}
catch(Exception e)
{
System.out.println("异常信息:"+e);
}
try
{
/*
* 方法级的异常*/
Exec(a,b);
}
catch(Exception e)
{
System.out.println("异常信息:"+e);
}
}
public static void Exec(int m,int n) throws Exception
{
int x;
x=m/n;
System.out.println(m+"/"+n+"="+x);
}
}