How to compare two array lists for similar objects which differ in at least one property in java?

Question

I have two array list. Each has list of Objects of type User.

The User class looks like below

    public class User {

    private long id;

    pri         


        

Answer 1

This is simple. Override equal method in your User class. One very simple implementation(you can enhance it by using null checks etc) can be like below:

@override
public boolean equals(Object obj) {
User other = (User) obj;
    if(this.id==other.id 
      && this.empCode.equals(other.empCode)
      && this.firstname.equals(other.firstname)
      && this.lastname.equals(other.lastname)
      && this.email.equals(other.email)){
          return true;
    }else{
        return false;
    }
}

Once done, you can use:

 for(user user: list1){
    if(!resultList.contains(user)){
       resultList.add(user);
    }
 }


 for(user user: list2){
    if(!resultList.contains(user)){
       resultList.add(user);
    }
 }