Sort ArrayList of Objects based on another array

Question

I want to sort arraylist of object based on another array using Java 7.

List A ={[id:1,name:"A"],[id:2,name:"B"],[id:3,name:"C"],[id:4,name:"D"]}

Array : {2,4}

Output: {[id:2,name:"B"],[id:4,name:"D"],[id:3,name:"C"],[id:1,name:"A"]}

Something same to the below question but need to implement the same in Java 7(without Lambda)

Sort ArrayList of Objects based on another array - Java

Then don't use lambda :)... imho, that's not similar... it's exactly the same. — hradecek
– hradecek, Commented Jun 20, 2018 at 6:25
You already got a working solution using Lambdas. Now all you need to do is understand what happens there and do it with Java 7 features... you should show that you attempted to solve your problem on your own over relying on us to port code for older Java-versions. — Ben
– Ben, Commented Jun 20, 2018 at 6:29
And then if you found a working solution for the problem without using any of the Java 8 features, also feel free to post it as an answer to your linked question so everyone who comes along that question can profit of it :) — Ben
– Ben, Commented Jun 20, 2018 at 6:31

double-beep · Accepted Answer · 2019-05-27 17:07:33Z

1

I suggest using:

    int[] index = {2, 4};
    List<Model> modelList = new ArrayList<>(Arrays.asList(new Model(1, "a"),
            new Model(2, "b"), new Model(3, "c"),
            new Model(4, "d")));
    Map<Integer, Model> modelMap = new HashMap<>();
    for (Model model : modelList) {
        modelMap.put(model.id, model);
    }
    // sort by index
    modelList.clear();
    for (int anIndex : index) {
        modelList.add(modelMap.get(anIndex));
        modelMap.remove(anIndex);
    }
    if (!modelMap.isEmpty()) {
        for (Map.Entry<Integer, Model> entry : modelMap.entrySet()) {
            modelList.add(entry.getValue());
        }
    }
    System.out.println(modelList);

edited May 27, 2019 at 17:07

double-beep

5,66019 gold badges43 silver badges50 bronze badges

answered Jun 20, 2018 at 7:03

jian hu

393 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Sort ArrayList of Objects based on another array

1 Answer 1

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related