Java异常抛出及自定义异常

throw  抛出异常

throws 抛出异常声明

首先自定义异常类（继承Exception类）

public class MyException extends Exception {
public MyException(String message){
super(message);
}
}


抛出异常
package yh;
public class Test {
public void g(int num) throws MyException{
if(num < 0)
throw new MyException("参数不能为负！");
else
System.out.println(num);
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Test t = new Test();
try{
t.g(1);
t.g(2);
t.g(-1);
t.g(5);
}catch(MyException e){
System.out.println(e.getMessage());
}
}
}


输出结果如下：