java - 基础 - 内部类

            package
             innerClass;


            public
            interface
             interfaceSchool {

    
            public
            void
             show();
}
        

            package
             innerClass;


            public
            class
             School{

    
            private
             String name;
    
            public
            static
             String location;

    School(String name){
        
            this.name = name;
    }
    public String getName(){
        returnthis.name;
    }

    publicvoid innerClassTest(){
        class localInnerClass{//局部内部类类似于局部变量，一般不会用到,不能用private public等修饰，可以用abstract和final修饰，使用的变量只能用final        }
    }

    publicclass Student{ //成员内部类public String name;
        public String schoolName;

        Student(String name){
            Student.this.name = name;
            schoolName = School.this.name; //可以直接调用外部类的私有属性        }
    }

    publicstaticclass StaticStudent{//静态内部类publicstatic String name;
        publicstatic String location;

        StaticStudent(String name){
            StaticStudent.this.name = name;
            StaticStudent.this.location = School.location; //静态内部类只能访问静态成员        }
    }

}

            package
             innerClass;


            import innerClass.School.Student;//不在这里引用的话下面写成School.Student stu1 = sch1.new Student("studentname1");也可以import innerClass.School.StaticStudent;//静态内部类和成员内部类导入方法一样publicclass Test {
    publicstaticvoid main(String[] args){
        //先定义外部类再构造内部类
        School sch1 = new School("schoolname1");
        Student stu1 = sch1.new Student("studentname1");
        //合并成一句
        Student stu2 = new School("schoolname2").new Student("studentname2");

        System.out.println(stu1.name);
        System.out.println(stu1.schoolName);

        System.out.println(stu2.name);
        System.out.println(stu2.schoolName);


         //匿名内部类, 通常是接口的子类，开发中可以省略一个类文件，相当于一个子类继承了School,一般用于接口的重写。
        interfaceSchool sch3 = new interfaceSchool(){
            publicvoid show(){
                System.out.println("我是一个匿名类重写的方法");
            }
        };
        sch3.show();


        //静态内部类的使用
        System.out.println("------Static------");
        School sch4 = new School("schoolname4");
        StaticStudent StaticStu1 = new StaticStudent("StaticStudent1");  //静态内部类可以直接声明        System.out.println(StaticStu1.name);
        System.out.println(StaticStu1.location);

        School sch5 = new School("schoolname4");
        sch5.location = "bbb";
        StaticStudent StaticStu2 = new StaticStudent("StaticStudent2");
        System.out.println(StaticStu2.name);
        System.out.println(StaticStu2.location);
        System.out.println(StaticStu1.name);//因为属性是静态的，所以共享改变
        System.out.println(StaticStu1.location);//因为属性是静态的，所以共享改变    }
}