static

package Dome;
import static java.lang.Math.random;
import static java.lang.Math.PI;
​
public class Test {
    public static void main(String[] args) {
        System.out.println(random());
        System.out.println(PI);
    }
}

package Dome;
​
public class Person {
    {//付初始值
        System.out.println("匿名方法快");
    }
    static {//静态方法只执行一次
        System.out.println("构造方法快");
    }
​
    public Person() {
        System.out.println("无参构造");
    }
​
    public static void main(String[] args) {
        Person s1 = new Person();
        System.out.println("=======");
        Person s2 = new Person();
​
​
    }
}

package Dome;
​
public class Dome07 {
    public static int age;//静态方法
    public double score;//非静态方法
​
    public static void main(String[] args) {
        Dome07 s1 = new Dome07();
        System.out.println(Dome07.age);
        System.out.println(s1.age);
        System.out.println(s1.score);
        new Dome07().run();
    }
    public static void go(){
​
    }
    public void run(){
​
    }
​
​
​
}

+++