我正在写一个出纳排队系统的程序。程序应该添加、编辑和删除客户信息：id、lastname、firstname和age。该计划应优先考虑或显示年龄超过60岁的客户，然后其他客户将跟随。
这是我的 CustomerInfo 班级。

public class CustomerInfo {
  //instance variables
  public int custID;
  public String lastname, firstname;
  public int age;

  //overloading constructors
  public CustomerInfo(int custID, String lastname, String firstname, int age) {
     this.custID = custID;
     this.lastname = lastname;
     this.firstname = firstname;
     this.age = age;
  }
  public CustomerInfo() {
     custID = 0;
     lastname = "";
     firstname = "";
     age = 0;
  }
  //setters or mutator methods
  public void setCustID(int custID) {
     this.custID = custID;
  }
  public void setLastName(String lastname) {
     this.lastname = lastname;
  }
  public void setFirstName(String firstname) {
     this.firstname = firstname;
  }
  public void setAge(int age) {
     this.age = age;
  }
  //getters or accessor methods
  public int getCustID() {
     return custID;
  }
  public String getLastName() {
     return lastname;
  }
  public String getFirstName() {
     return firstname;
  }
  public int getAge() {
     return age;
  }
}

这是我的添加和查看代码：

import java.util.*;
import javax.swing.*;

public class FinalProject {
    public static void main(String[] args) throws IOException, InterruptedException {
        Scanner input = new Scanner(System.in);
        CustomerInfo[] cusInfo = new CustomerInfo[5];
        ArrayList<Integer> cusId = new ArrayList<>();
        ArrayList<String> lastNames = new ArrayList<>();
        ArrayList<String> firstNames = new ArrayList<>();
        ArrayList<Integer> ages = new ArrayList<>();
        ArrayList<Integer> cusIdSenior = new ArrayList<>();
        ArrayList<String> lastNamesSenior = new ArrayList<>();
        ArrayList<String> firstNamesSenior = new ArrayList<>();
        ArrayList<Integer> agesSenior = new ArrayList<>();
        int count = 0, countSenior = 0;
        CustomerInfo ci = new CustomerInfo();
        int customernum = 0;

        System.out.println("ADD CUSTOMER DETAILS");

        for(int i = 0; i < 5; i++) {
           System.out.print("Customer's ID           : ");
           int custID = input.nextInt();
           System.out.print("Customer's Last Name    : ");
           String lastname = input.next();
           System.out.print("Customer's First Name   : ");
           String firstname = input.next();
           System.out.print("Customer's Age          : ");
           int age = input.nextInt();
           CustomerInfo c = new CustomerInfo(custID, lastname, firstname, age);

           cusInfo[customernum] = c;
           customernum++;
           System.out.println();
        }

        //VIEW CUSTOMER DETAILS
        if(customernum == 0) {
          JOptionPane.showMessageDialog(null, "QUEUE IS EMPTY. NOTHING TO VIEW.");
        }
        else{
           System.out.println("VIEW CUSTOMER DETAILS");
           for(int i = 0; i < customernum; i++) {
              cusId.add(ci.custID);
              lastNames.add(ci.lastname);
              firstNames.add(ci.firstname);
              ages.add(ci.age);
              count++;
           }
           for(int i = 0; i < count; i++) {
              if(ages.get(i) >= 60) {
                cusIdSenior.add(cusId.get(i));
                lastNamesSenior.add(lastNames.get(i));
                firstNamesSenior.add(firstNames.get(i));
                ages.add(ages.get(i));
                countSenior++;
              }
           }
           for(int i = 0; i < countSenior; i++) {
             System.out.printf("Customer ID         : %d\n", cusIdSenior.get(i));
             System.out.printf("Customer Last Name  : %s\n", lastNamesSenior.get(i));
             System.out.printf("Customer First Name : %s\n", firstNamesSenior.get(i));
             System.out.printf("Customer Age        : %s\n", agesSenior.get(i));
           }
           for(int i = 0; i < count; i ++) {
              if(ages.get(i) < 60 && ages.get(i) > 0) {
                 System.out.printf("Customer ID         : %d\n", cusId.get(i));
                 System.out.printf("Customer Last Name  : %s\n", lastNames.get(i));
                 System.out.printf("Customer First Name : %s\n", firstNames.get(i));
                 System.out.printf("Customer Age        : %s\n", ages.get(i));
              }
           }
        }
    }
}

问题是在我运行并输入所有元素后，它不会显示语句，程序将立即退出。