Question

我试图遍历我的ArrayList并找到一个值，该值等于我使用while循环为其设置的条件。一旦程序遍历用户并找到与条件匹配的值，我试图让它从列表中删除该用户。一切似乎都运行正常，但它似乎没有从数组列表中删除任何东西。这是代码：

主要课程

package main;

public class Main{
 public static void main(String[] args) {
    System.out.println("****************For loop****************");
       for (int counter=2; counter<=40; counter+=2) {
       System.out.println(counter);
    }
    System.out.println("****************While loop****************");

    int counter = 1;
    int increment = 2;
    int loopexeccounter = 0;
    while (counter <= 500) {
        loopexeccounter = loopexeccounter + 1;
        System.out.println(counter);
    counter = counter + increment++;
    }
System.out.print("This loop iteratted "+loopexeccounter+" times.\n");
     {

     //public User callUserGroup;   
UserGroup userGroupObject = new UserGroup();
userGroupObject.removeFirstUser();
userGroupObject.removeLastUser();
userGroupObject.removeUser();
System.out.println("***********Number of users Array List***********");
System.out.println(userGroupObject.userGroup.size());
System.out.println("***********User's details***********");
for (User curUser : userGroupObject.getUserGroup())
{
   System.out.println(curUser.toString()); 
} }
}
}

UserGroup类（用于制作数组列表并执行函数）

package main;
import java.util.ArrayList;
import java.util.Iterator;

public class UserGroup {

ArrayList<User> userGroup = new ArrayList<>();
User userOne;
public UserGroup()
{
  addUser(new User("lnb1g16", "Student", "Lee"));
  addUser(new User("hpf1g17", "Staff", "Harry"));
  addUser(new User("jks1g25", "Student", "Jordon"));
  addUser(new User("ohw1237", "Staff", "Oliver"));
  addUser(new User("ahs1213", "Student", "Jordon"));
  addUser(new User("tqn1294", "Student", "Taylor"));
}

public void addUser(User inUser)
{
  //userGroup.add(new User("LeeB123", "Staff", "Lee"));
  userGroup.add(inUser);
}
public ArrayList<User> getUserGroup() {
    return userGroup;
}
public void removeFirstUser()  {
    userGroup.remove(0);

}
public void getArrayListSize()  {
    userGroup.size();
}
public void removeLastUser()  {
    userGroup.remove(4);
}
public void removeUser()  {
    Iterator<User> it = userGroup.iterator();    
    while (it.hasNext()) {
        User xxx = it.next();

        if (xxx.equals("jks1g26")) {

            it.remove();
        }
    }

}
}

用户类（定义用户的详细信息）

package main;

class User {

  String username;
  String userType;
  String name;


    User(String username, String userType, String name) {

    this.username = username;
    this.userType = userType;
    this.name = name;
    }

  public String getUsername() {
      return username;
  }

  public String getUserType() {
      return userType;
  }

   public String getName() {
      return name;
  }

  public String setUserType(String admin) {
      return userType = admin;
  }
  @Override
public String toString() {
    return username + " " + userType;
}
}

感谢任何帮助。

如何遍历数组列表并删除用户？

0 个答案: