Java 忽略对象Arraylist中的重复项

我有一个包含许多对象的数组列表。我想从中删除重复的对象。。我用TreeSet和Comparator尝试了下面的选项，但它不起作用。列表中添加了以下类对象

    public class Student {
    private String name;
    private String location;
    private int score;
    private int age;
    private String department;

    Student(){}
    Student(String sName,String loc,int ag,int scr,String dep){
        setName(sName);
        setLocation(loc);
        setScore(scr);
        setAge(ag);
        setDepartment(dep);
    }

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getLocation() {
        return location;
    }
    public void setLocation(String location) {
        this.location = location;
    }
    public int getScore() {
        return score;
    }
    public void setScore(int score) {
        this.score = score;
    }
    public int getAge() {
        return age;
    }
    public void setAge(int age) {
        this.age = age;
    }
    public String getDepartment() {
        return department;
    }
    public void setDepartment(String department) {
        this.department = department;
    }


}

下面是我的主课

import java.util.ArrayList;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Set;
import java.util.TreeSet;


public class MyMain {
    public static void main(String[] args) {
        Student s1= new Student("John","Aus",25,100,"Finance");
        Student s2= new Student("John","Aus",25,100,"Finance");
        Student s3= new Student("John","Aus",26,100,"Finance");
        Student s4= new Student("Alex","Ind",20,101,"Finance");
        Student s5= new Student("Alex","Ind",20,101,"Finance");
        Student s6= new Student("Alex","Ind",28,101,"Finance");
        ArrayList<Student> studentsList= new ArrayList<Student>();

        studentsList.add(s1);
        studentsList.add(s2);
        studentsList.add(s3);
        studentsList.add(s4);
        studentsList.add(s5);
        studentsList.add(s6);       

        for(int i=0;i<studentsList.size();i++){
            Student s=(Student)studentsList.get(i);
            System.out.println(i+ "  "+s.getName()+" "+s.getLocation()+" "+s.getAge()+" "+s.getScore()+" "+s.getDepartment());
        }

        Set set = new TreeSet(new Comparator<Student>() {

            @Override
            public int compare(Student s1, Student s2) {
                if( s1.getName().equalsIgnoreCase(s2.getName()) && s1.getLocation().equalsIgnoreCase(s2.getLocation()) && s1.getScore()==s2.getScore()){
                    return 0;
                }               
                return 1;
            }



        });     
        set.addAll(studentsList);
        studentsList.clear();
        studentsList.addAll(set);

        System.out.println("---------Final Result----------");
        for(int i=0;i<studentsList.size();i++){
            Student s=(Student)studentsList.get(i);
            System.out.println(i+ "  "+s.getName()+" "+s.getLocation()+" "+s.getAge()+" "+s.getScore()+" "+s.getDepartment());
        }       

    }

}

但我的预期产出是

0  John Aus 100 25 Finance
1  Alex Ind 101 20 Finance

请帮我做这个。这种方法正确吗？另外，我希望保持Student类的完整性（不能重写equals和hashCode）

请注意

您发布的结果是有效的 在您的竞争对手内，您可以检查：

名字

位置

得分

这就是为什么你会得到副本-因为分数不同您刚刚交换了年龄和分数参数，仅此而已

Student(String sName,String loc,int scr,int ag,String dep)

Student s1= new Student("John","Aus",25,100,"Finance");

---

重写

等于

和/或

hashCode

以何种方式不使

Student

保持不变？我认为comparator正在做您希望它做的工作。问题在于您向Student的构造函数输入参数的顺序。请使用

Set

以避免重复。正如你提到的，这是我在代码中的错误。刚刚更新过，效果很好。在进行此类比较时，只需再澄清一点，列表中元素的顺序是否重要？列表中元素的顺序对结果没有影响（将保持不变）。。至于性能-这恐怕是另一个问题：）哈哈：）这里有一些有趣的事情给你：谢谢，我会检查网址。。。同时，我刚刚向列表中添加了3个对象，如下所示，但现在最终列表包含重复项。。。看来它不起作用了。。。。学生s7=新学生（“吉姆”，“工业”，28102，“营销”）；学生s8=新生（“吉姆”，“工业”，28102，“营销”）；学生s9=新学生（“蚂蚁”，“Ind”，29102，“营销”）；

Student(String sName,String loc,int scr,int ag,String dep)

Student s1= new Student("John","Aus",25,100,"Finance");