Java之static关键字

package day02;
/*
static关键字
 1.开发中，如何确定一个属性是否要声明为static的？
   >属性是可以被多个对象所共享的，不会随着对象的不同而不同(例如:银行的利率，或者最小余额等)
 */
public class static静态 {
    public static void main(String[] args) {
        chinese c1 = new chinese();
        chinese c2 = new chinese();
        c1.name ="da";
        System.out.println(c1.name);
        c1.ids=1;
        c2.ids=2;
        System.out.println(chinese.ids);
    }
}
class chinese{
    String name;
    static int ids;
        }


*********************************************************************************************************

//银行的例子
bank.java

package day02;

public class bank {
    private int id;//账号
    private String pwd = "000000";//密码
    private double balance;//余额

    private static double interestRate;//利率
    private static double minMoney = 0.00;//最小余额
    private static int init = 1001;//用户自动生成id
//    无参构造器
    public bank(){
        id = init++;
    }
//    带参数的构造器
    public bank(String pwd,double balance){
        id = init++;
        this.pwd = pwd;
        this.balance = balance;
    }


//    get and set方法
    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getPwd() {
        return pwd;
    }

    public void setPwd(String pwd) {
        this.pwd = pwd;
    }

    public double getBalance() {
        return balance;
    }

    public void setBalance(double balance) {
        this.balance = balance;
    }

    public static double getInterestRate() {
        return interestRate;
    }

    public static void setInterestRate(double interestRate) {
        bank.interestRate = interestRate;
    }

    public static double getMinMoney() {
        return minMoney;
    }

    public static void setMinMoney(double minMoney) {
        bank.minMoney = minMoney;
    }

    @Override
    public String toString() {
        return "bank{" +
                "id=" + id +
                ", pwd='" + pwd + '\'' +
                ", balance=" + balance +
                '}';
    }
}

****************************************************************
bankTest.java

package day02;

public class bankTest {
    public static void main(String[] args) {
        bank bank0 = new bank();
        bank bank1 = new bank("1223423",2000);
        bank.setInterestRate(0.012);
        bank.setMinMoney(100);
        System.out.println(bank0);
        System.out.println(bank1);
        System.out.println(bank.getInterestRate());
        System.out.println(bank.getMinMoney());

    }
}