内部类注意事项[huiqinbo]错误提示：Multiple markers at this line- No enclosing instance of ty

今天周六没事就写点java方面的基础知识，平时在Q上也会有网友问我关于内部类报错方面的问题，如报这样的错误：

【

No enclosing instance of type TestThread is accessible. Must qualify the allocation with an enclosing instance of type TestThread (e.g. x.new A() where x is an instance of
 TestThread).

】

或是：

【

Multiple markers at this line
 - No enclosing instance of type TestThread is accessible. Must qualify the allocation with an enclosing instance of type TestThread (e.g. x.new A() where x
  is an instance of TestThread).
 - The value of the local variable tt is not used

】

 

其实这样的错误提示不是很明了，不太清楚，但你只要把握几点就不能出错：

在公共类(public claass xx {})中创建并使用内部类时无非有这两种形式：

1.

public class Test{

    public static void main(String args[]){

         TicketThread ticket = new TicketThread ();

          new Thread (ticket).start();

          new Thread (ticket).start();

          new Thread (ticket).start();

    }

 

    private static class TicketThread implements Runnable{ //这里必须加上static 因为在main方法中要用到,且

                                                                               //main方法是static的。若不在main方法中用可去掉

         public void run(){

            .....................

         }

 

    }

 }

 

2.也可以这样来写：

public class Test{

    public static void main(String args[]){

         TicketThread ticket = new TicketThread ();

          new Thread (ticket).start();

          new Thread (ticket).start();

          new Thread (ticket).start();

    }

 }

 

class TicketThread implements Runnabl{       

         public void run(){

            .....................

         }

}

 

总结：通常报以上两种错误提示的问题主要是因为没有处理好static 。

先写到这里，

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