Java 基础教程:static只运行一次

[java]代码库

class Count {
public static int counter;
static {//只运行一次
counter
= 123;
System.out.println("Now in static block.");
      
      
}
public void test(){
System.out.println("test method=="+counter);
}
}
public class Test {
public static void main(String args[]) {
System.out.println("counter=" + Count.counter);
new Count().test();
}
}
运行结果是:
Now in static block.
counter=123
test method==123
5:静态 import
当我们要获取一个随机数时,写法是:
public class Test {
public static void main(String[] args) {
double randomNum = Math.random();
System.out.println("the randomNum=="+randomNum);
}
}//源代码片段来自云代码http://yuncode.net