自定义“无效名字异常”
1.编译时异常，直接继承Exception
2.运行时异常，直接继承RuntimeException
public class IllegalNameException extends Exception{//编译时异常
//public class IllegalNameException extends RuntimeException{//运行时异常
public IllegalException(){
}
public IllegalException(String msg){
super(msg);
}
}
//定义一个消费者类
public class CustomerService{
public void register(string name)throws IllegalException{
if(name.length()<6){
//异常
//创建异常对象
IllegalException e=new IllegalException("用户名长度不能少于六位");
throw e;
//throw IllegalException("用户名长度不能少于六位");
}
//如果执行到此处，说明用户名是合法的。
System.out.println("用户名合法，注册成功！");
}
}
//测试类
public class Test{
public static void main(String[] args){
String name="nihao";
CustomerService cs=new CustomerService();
try{
cs.register("nihao");
}catch(IllegalNameException e){
System.out.println(e.getMessage());
}
}
}
