静态static关键字修饰成员变量

Java 评论

静态static关键字修饰成员变量

如果一个成员变量使用了static关键字,那么这个变量就不再属于对象自己,而是属于所在的类.多个对象共享同一份数据.



格式:

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static int number;
public static String name;
private static float jiGe;


使用静态成员变量:

类名.静态成员变量;

对象名.静态成员变量;



修改静态成员变量的值:

类名.静态成员变量 = 1;

对象名.静态成员变量 = 1;


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public class Main15{
    public static void main(String[] args) {
        Student one = new Student("张三丰",102);
        Student two = new Student("张无极",23);
        Student three = new Student("赵敏",18);
        Student four = new Student("周芷若",18);
        //使用静态成员变量
        Student.room = "101教师";
        System.out.println("名字:" + one.getName() + "  年龄:"
                + one.getAge() + "  课室" + one.room
                + "  学号:" + one.getId() );

        System.out.println("名字:" + two.getName() + "  年龄:"
                + two.getAge() + "  课室" + two.room
                + "  学号:" + two.getId() );


        System.out.println("名字:" + three.getName() + "  年龄:"
                + three.getAge() + "  课室" + three.room
                + "  学号:" + three.getId() );

        System.out.println("名字:" + four.getName() + "  年龄:"
                + four.getAge() + "  课室" + four.room
                + "  学号:" + four.getId() );
    }
}
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public class Student{
    private String name;
    private int    age;
    public static String  room;//公开的静态成员变量
    private int id;
    private static int countIdNumber;//私有的静态成员变量

    public int getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
        id = ++countIdNumber;
    }

    public Student() {
        id = ++countIdNumber;
    }
}




快捷键:

​ 数字.fori按下回车或tab键之后,会自动生成一个循环6次的for循环语句

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for(int i = 0;i < 6;i++)
{

}



数组名.fori

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for(int i = 0;i < 数组名.lenght;i++)
{

}


变量名.sout

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System.out.println(变量名);


对象.sout

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System.out.println(对象名);


对象名.成员变量.sout

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System.out.println(对象名.成员变量);


数组名[i].sout

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System.out.println(数组名[i]);




YanChen

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