Java – filter collections using lambdaj

I have two classes:

public class Order{
    private Integer id;
    private List<Position> positions;
    ...
}

public class Position{
    private Integer id;
    private String content;
    ...
}

Now I have a list of orders and want to get all orders with specific content Now I do this:

List<Order> orders = ... ;

List<Order> outputOrders = ... ;
for(Order order : orders){
    if(select(order.getPositions(),having(on(Position.class).getContent(),equalTo("Something"))).size() != 0){
        outputOrders.add(order);
    }
}

Is there a better way to use lambdaj?

Thank you in advance

Solution

How about that: use org hamcrest. Matchers. hasItem？

List<Order> outputOrders =
        filter(having(on(Order.class).getPositions(),hasItem(having(on(Position.class).getContent(),equalTo("Something")))),orders);