简单实现Java通讯录系统

import java.util.Scanner;
class Person
  {
   String name;
   String number;
  }
class connect
{
   Person a[];
   int number;
   public connect()
   {
     a=new Person[100];
     number=0;
   } 

   public String add(String name,String number)
   {
    if(number == "0")
    System.out.println("请先添加联系人!");
    if(this.number>99)
    return "添加失败";
    a[this.number]=new Person();
    a[this.number].name=name;
    a[this.number].number=number;
    this.number++;
    return "添加成功";
   } 

   public Person seek(String name)
   {
    if(number == 0)
    System.out.println("请先添加联系人!");
    for(int i=0;i<number;i++)
    { 
     if((a[i].name).equals(name))
     {
      System.out.println("联系人： "+a[i].name+" 电话："+a[i].number);
      return a[i];
     }
    }
    return null; 
   }

   public void look()
   {
    if(number == 0)
    System.out.println("请先添加联系人！");
    for(int i=0;i<number;i++)
    {
     System.out.println("联系人 "+a[i].name+" 电话 "+a[i].number);
    }
   }

   public String delete(String name)
   {
    if(number == 0)
    System.out.println("请先添加联系人：");
    for(int i=0;i<number;i++)
    { 
     if((a[i].name).equals(name))
     {
      a[i]=a[this.number-1];
      number=number-1;
      return "删除成功";
     }
    }
    return "删除失败";
   }
}
public class text1
{
 public static void main(String[]args)
 {
  Scanner sc=new Scanner(System.in);
  Scanner input = new Scanner(System.in);
  System.out.println("ttt欢迎使用通讯录系统n");
  System.out.println("ttt1.创建用户nnttt2.退出n");
  System.out.println("____________________________________________________________________nn");
  System.out.print("请选择相应选项：");
  int num2 = sc.nextInt(); 
  while(num2!=2)
   {
    switch (num2)
    {
    case 1:
     {
      connect c = new connect();
      System.out.println("ttt1.浏览n");System.out.println("ttt2.查找n");
      System.out.println("ttt3.添加n");System.out.println("ttt4.删除n");
      System.out.println("ttt5.退出n");System.out.println("请选择相应选项：");
      System.out.println("输入指令：");
      int num1 = input.nextInt();
      switch (num1)
      {
       case 1:c.look();break;
       case 2:
       {
        System.out.println("输入查找的名字：");
        String n1 = sc.next();c.seek(n1);
       }break;
       case 3:
       {
        System.out.println("输入要添加的人数："); 
        System.out.println("enter:");
        int s=sc.nextInt();
        for(int i=0;i<s;i++)
        {
         System.out.println("请输入第"+(i+1)+"个人的名字：");
         String name=sc.next();
         String number=sc.next();
         c.add(name,number);
        }
       }break;
       case 4:
       {
        System.out.println("输入删除的姓名：");
        String n3 = sc.next();c.delete(n3);
       }break;
       default:
        {
         System.out.println("ttt谢谢您的使用n");
         System.exit(0);
        }
       } 
      }break;
    case 2:System.out.println("ttt谢谢您的使用n");break;
    default:System.out.println("输入有误！");num2=2;
    }
   }
 }
}