static关键字详解

//static 静态publicclassStudent{privatestaticintage;//静态的变量 多线程privatedoublescore;//非静态的变量publicvoidrun(){}publicstaticvoidgo(){}publicstaticvoidmain(String[]args){//run();//报错必须把对象new出来Student.go();Studentstudent1newStudent();System.out.println(Student.age);System.out.println(student1.age);System.out.println(student1.score);}}publicclassPerson{//2赋初始值{System.out.println(匿名代码块);}//1:只执行一次static{System.out.println(静态代码块);}//3publicPerson(){System.out.println(构造方法);}publicstaticvoidmain(String[]args){Personperson1newPerson();/* 静态代码块 匿名代码块 构造方法 */System.out.println();Personperson2newPerson();/* 匿名代码块 构造方法 */}}//静态导入包importstaticjava.lang.Math.random;importstaticjava.lang.Math.PI;publicclassTest{publicstaticvoidmain(String[]args){System.out.println(random());System.out.println(PI);}}类被final定义就不能继承了