gistfile1.txt

package org.sample;

import java.util.ArrayList;

import static org.hamcrest.CoreMatchers.equalTo;
import static org.mockito.Matchers.argThat;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.verify;

public class Sample {

    public static void main(String... args) {
        MainActivity activity = mock(MainActivity.class);
        MyRequest subject = new MyRequest(activity);
        ArrayList<MyModel> list = new ArrayList<>();
        list.add(new MyModel(1));
        subject.makeRequest();
        verify(activity).handleSuccess(argThat(equalTo(list)));
    }

    static class MainActivity {
        public void handleSuccess(ArrayList<MyModel> list) {
        }
    }

    static class MyRequest {

        MainActivity mainActivity;

        MyRequest(MainActivity mainActivity) {
            this.mainActivity = mainActivity;
        }

        void makeRequest() {
            ArrayList<MyModel> list = new ArrayList<>();
            list.add(new MyModel(1));
            mainActivity.handleSuccess(list);
        }
    }

    static class MyModel {
        final int id;

        MyModel(int id) {
            this.id = id;
        }

        @Override
        public boolean equals(Object o) {
            System.out.println("Equals invoked: " + toString());
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;

            MyModel myModel = (MyModel) o;

            if (id != myModel.id) return false;

            return true;
        }

        @Override
        public int hashCode() {
            return id;
        }

        @Override
        public String toString() {
            return "MyModel{" +
                    "id=" + id +
                    '}';
        }
    }
}