Test.java

import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;

import io.reactivex.Observable;
import io.reactivex.annotations.NonNull;
import io.reactivex.functions.Consumer;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotEquals;

public class Test {

	private Observable<Double> retrofit() {
		return Observable.just(Math.random()).delay(1, TimeUnit.SECONDS);
	}

	@org.junit.Test
	public void test() throws InterruptedException {
		final List<Double> results = new ArrayList<>();

		Consumer<Double> onNext = new Consumer<Double>() {
			@Override
			public void accept(@NonNull Double aDouble) throws Exception {
				results.add(aDouble);
			}
		};

		getStuff().subscribe(onNext);
		Thread.sleep(500);
		getStuff().subscribe(onNext);
		Thread.sleep(510);
		getStuff().subscribe(onNext);
		Thread.sleep(1100);

		assertEquals(results.get(0),results.get(1) );
		assertNotEquals(results.get(1),results.get(2) );

	}

	private Observable<Double> stuff = retrofit().share();

	public Observable<Double> getStuff() {
		return stuff;
	}

}