1.7Oob 静态成员

1）
public class Exse3 {
    static int iCounter = 0;
    String name;
    boolean bGender = false;
    int iAge;
    double dHeight;
    double dWeight;
    public void getCounter() {
        System.out.println("学生总人数为"+(++iCounter));
    }
    public void getInfo() {
        System.out.print("姓名"+name);
        System.out.print("性别"+bGender);
        System.out.print("年龄"+iAge);
        System.out.print("身高"+dHeight);
        System.out.print("体重"+dWeight);
    }
    public Exse3() {
        iAge = 29;
        dHeight = 170;
        dWeight = 65;
    }
}

public class Textexse3 {
    public static void main(String[] args) {
        Exse3 st1 = new Exse3();
        Exse3 st2 = new Exse3();
        Exse3 st3 = new Exse3();
        st3.getInfo();
        st3.getCounter();
        for(int i=0;i<3;i++) {
            Exse3 st = new Exse3();
            st.getInfo();
            st.getCounter();
        }
        System.out.println(Exse3.iCounter);

    }
}

1：输出结果为：

姓名null性别false年龄29身高170.0体重65.0学生总人数为2
姓名null性别false年龄29身高170.0体重65.0学生总人数为3
姓名null性别false年龄29身高170.0体重65.0学生总人数为4
4

结论：静态成员变量是类的属性，无论类生成多少个实例，这些实例都共用这一共同的属性值，