import java.util.ArrayList;
public class ArrayListTest3 {
public static void main(String[]args){
//要求:1.main方法中定义一个集合,存入三个用户对象
//用户属性为:id,username,password
//2要求:定义一个方法,根据id查找对应的用户信息
//如果存在,返回id
//如果不存在,返回-1
ArrayList<user> list=new ArrayList<>();
user u1=new user("244213","zhangsan","abc123QwQ");
user u2=new user("244214","lisi","1234qwer");
user u3=new user("244215","wangwu","12345678");
list.add(u1);
list.add(u2);
list.add(u3);
int result=getIndex("24213",list);
System.out.println(result);
}
public static int getIndex(String id,ArrayList<user> list)
{for(int i=0;i<list.size();i++)
{
user u=list.get(i);
String uid=u.getId();
if(uid.equals(id))
{
return i;
}
}
return -1;
}
}