java - 从链接列表中删除特定元素时遇到问题

Question

我被分配了一个任务，以链表的形式创建一个用 Java 编写的基于寄存器的小型程序。我首先创建一个学生类(class)，然后为该类(class)创建一个测试人员文件。接下来，在注册表文件中，我列出了我的方法和构造函数，并且正在编写测试程序文件来测试我的所有方法。

但是，当我尝试从链接列表中删除特定元素时遇到麻烦，我希望能够删除学生，通过其个人的 StudentID 引用他们，但不知道如何执行此操作。

在尝试解决问题时，我遇到了 removeFirstOccurrence(Object o) 方法。这是正确的使用方法吗？

任何帮助将不胜感激。

学生文件代码:

public class Student {

private String foreName;
private String surName;
private int studentID;

//declaring the variables needed for my student


public Student (String foreName, String surName, int studentID)
{
    this.foreName = foreName;
    this.surName = surName;
    this.studentID = studentID;
}
//constructor to set out what a student needs



public String getForeName() {
    return foreName;
}

public String getSurName() {
    return surName;
}

public int getStudentID() {
    return studentID;
}

public void setForeName(String foreName) {
    this.foreName = foreName;
}

public void setSurName(String surName) {
    this.surName = surName;
}

public void setStudentID(int studentID) {
    this.studentID = studentID;
}

// getters and setters for my variables

public String toString ()
{

    return getClass().getName() + "foreName = " + foreName + "surName = " + surName + "studentID = " + studentID;
}
//my toString method

}

注册表文件代码:

import java.util.*;
public class Registry {


LinkedList<String> studentList
        = new LinkedList<String>();
//setting my type parameter


public Registry() {}
//empty constructor to hold arguements

public void addStudent(String aStudent)
{
    this.studentList.addLast(aStudent);
}



public void deleteStudent(int studentID) 
{
    //????         
}


@Override public String toString()
{
  return "Registry";
}



public String format()
{
}

注册表测试器文件代码:

import java.util.*;

public class RegistryTester {
public static void main (String[] args)
{
    LinkedList<String> studentList
            = new LinkedList<String>();




    System.out.println("Test 1");
    System.out.println("Methods tested: addStudent, constructor");
    System.out.println("********************");

    studentList.add("Joe Perkins 123");        
    studentList.addLast("Shilpa Gupta 1234");
    studentList.addLast("Seany Ray 12345");
    // adding 3 students to my list

    System.out.println(studentList);

}

}

Answer 1

1. 将List定义为Student的List

   LinkedList<Student> studentList = new LinkedList<Student>();
   

2. 重写 Student 类中的 hashCode() 和 equals() 方法。

   public boolean equals(Object obj) {
      if (obj instanceof Student) {
        return studentID == ((Student)obj).getStudentID();
      }
     return false;
   }
   
   public int hashCode() {
      return studentID;
   }
   

3. 定义方法:

   public void addStudent(Student aStudent)
   {
        this.studentList.addLast(aStudent);
   }
   
   
   
   public void deleteStudent(Student astudent) 
   {
       this.studentList.remove(aStudent)       
   }