Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

Java List with two Objects inside: List<Object o, Object p>

Is it possible to do the following?

List<Object o, Object p> listWithTwoObjects;

I want to retrieve data from a database and save it into this list, concretely in this way

Query query = "retrieve all posts and username, which this user posted";
List<Object o, Object p> userAndPost = query.getResultList();

o is the username, and p is the post. I can then render this to my template and show each post with its user.

My question is about the List with two Objects inside. Is it possible and if yes, how and where is the documentation for this?

like image 216
doniyor Avatar asked Nov 29 '22 14:11

doniyor


2 Answers

You can define a Pair class as follows:

public class Pair
{
    String username;
    int post;

    public Pair(String username, int post)
    {
        this.username = username;
        this.post = post;
    }
}

and then simply use List<Pair>, for example:

List<Pair> pairs = new ArrayList<Pair>();
pairs.add(new Pair("doniyor", 12345));

// ...

Pair p = pairs.get(0);
System.out.pritnln(p.username); // doniyor
System.out.pritnln(p.post); // 12345
like image 148
Eng.Fouad Avatar answered Dec 05 '22 06:12

Eng.Fouad


If i understand correctly you want to have all posts of a user, so instead of using List you should use Map:

Map<String,List<Post>> map = new HashMap<String,List<Post>>();

Then, the key(String) would be the userName and the value would be a list of Post objects.

like image 41
Tomer Avatar answered Dec 05 '22 07:12

Tomer