static关键字详解
package com.oop.demo07;
public class Student {
private static int age; //静态变量
private double score; //非静态变量
public void run(){
go();
}
public static void go(){
System.out.println("hh");
}
public static void main(String[] args) {
go();
Student s1 = new Student();
System.out.println(Student.age);
System.out.println(s1.score);
System.out.println(s1.age);
}
}
package com.oop.demo07;
public class Person {
//2.赋初值~
{
System.out.println("匿名代码块");
}
//1.只执行一次
static {
System.out.println("静态代码块");
}
//3
public Person(){
System.out.println("构造方法!");
}
public static void main(String[] args) {
Person person = new Person();
System.out.println("===============");
Person person1 = new Person();
}
}
通过final修饰的类没有子类
package com.oop.demo07;
//静态导入包~
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);
}
}