从java中的另一个类获取静态变量 [英] Accesing static variable from another class in java

问题描述

在我的多线程服务器中，我有一个队列作为链表实现。我想从另一个类访问此队列。两个类都在同一个包中。我试图把这个队列作为public static并通过getter访问它，但没有成功有人告诉我什么是确切的问题。

I had a queue implemented as linked list in my multithreaded server. I want to access this queue from another class. Both classes are in the same package. I tried making this queue as public static and accessing it through getter, but without success Can somebody tell me what is the exact problem.

这是我的代码：
队列声明：

This is my code: Queue Declaration:

public static Queue<Request> q=new ConcurrentLinkedQueue<Request>();

public static void setQ(Queue<Request> q) {
        Connection.q = q;
    }

    public static Queue<Request> getQ() {
        return q;
    }

访问队列：

Queue<Request> queue=new ConcurrentLinkedQueue<Request>(); 
queue=Connection.getQ();

在连接线程中将值添加到队列

Adding Value to Queue in thread of connection

q.add(r);

推荐答案

您可以访问使用符号 ClassName.memberName ：

public class Foo {
    public static String bar = "hi there";
}

public class Thing {
    public static void main(String[] args) {
        System.out.println(Foo.bar); // "hi there"
   }
}

public static 数据成员通常不是一个好主意（除非他们 final ），但如果你需要一个，那就是你怎么做。

public static data members are usually not a great idea (unless they've final), but if you need one, that's how you do it.

这篇关于从java中的另一个类获取静态变量的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！