IteratorOfSupplierMain.java

import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.Optional;
import java.util.Spliterator;
import java.util.Spliterators;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Supplier;
import java.util.stream.Stream;
import java.util.stream.StreamSupport;

public class IteratorOfSupplierMain {

	public static void main(String[] args) {
		Iterator<Model> iterator = IteratorOfSupplier.of(new ModelSupplier());
		Spliterator<Model> spliterator = Spliterators.spliteratorUnknownSize(
				iterator, Spliterator.NONNULL);
		Stream<Model> stream = StreamSupport.stream(spliterator, false);
		stream.forEach(System.out::println);
		System.out.println("Done");
	}
}

class IteratorOfSupplier<T> implements Iterator<T> {

	Optional<T> next = Optional.empty();
	final private Supplier<T> supplier;

	private IteratorOfSupplier(Supplier<T> supplier) {
		this.supplier = supplier;
	}

	public static <T> IteratorOfSupplier<T> of(Supplier<T> supplier) {
		return new IteratorOfSupplier<T>(supplier);
	}

	@Override
	public boolean hasNext() {
		if (next.isPresent()) {
			return true;
		} else {
			next = Optional.ofNullable(supplier.get());
			return next.isPresent();
		}
	}

	@Override
	public T next() {
		if (next.isPresent() || hasNext()) {
			T result = next.get();
			next = Optional.empty();
			return result;
		} else {
			throw new NoSuchElementException();
		}
	}

}

class ModelSupplier implements Supplier<Model> {

	private final AtomicInteger counter = new AtomicInteger(0);

	@Override
	public Model get() {
		if (counter.get() < 100)
			return new Model("name" + counter.incrementAndGet());
		return null;
	}
}

class Model {
	private String name;

	public Model(String name) {
		this.name = name;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	@Override
	public String toString() {
		return "Model [" + (name != null ? "name=" + name : "") + "]";
	}

}