【Java 基础项目 - - Bank项目4】 对象构造/跨package调用

UML设计:

文件组织:

(注: 在bank4中,直接调用bank3的内容, 不再重复编写代码即可!)

代码编写Bank.java:

package Banking_4;

import Banking_3.*;

public class Bank {
    private Customer[] customers ;   //用于存放客户
    private int numberofCustomers; //用于记录Customer的个数

    public Bank(){
        numberofCustomers=0;
        customers = new Customer[100];  ///这里记得要初始化!不然要发生java.lang.NullPointerException
    }
    public void addCustomer(String f,String l){
        int i=this.numberofCustomers++;
        customers[i]=new Customer(f,l);//新建一个构造对象
    }

    public int getNumOfCustomers() {
        return numberofCustomers;
    }
    public Customer getCustomer(int index) {
        return customers[index];
    }
}

2/TestBanking4.java

package Banking_4;

import Banking_3.*;

public class Bank {
    private Customer[] customers ;   //用于存放客户
    private int numberofCustomers; //用于记录Customer的个数

    public Bank(){
        numberofCustomers=0;
        customers = new Customer[100];  ///这里记得要初始化!不然要发生java.lang.NullPointerException
    }
    public void addCustomer(String f,String l){
        int i=this.numberofCustomers++;
        customers[i]=new Customer(f,l);//新建一个构造对象
    }

    public int getNumOfCustomers() {
        return numberofCustomers;
    }
    public Customer getCustomer(int index) {
        return customers[index];
    }
}

运行结果:

Customer [1] is Simms, Jane
Customer [2] is Bryant, Owen
Customer [3] is Soley, Tim
Customer [4] is Soley, Maria