Filtering collections with lambdaj

collections, filtering, java, lambdaj

Solution

What about this one: use `org.hamcrest.Matchers.hasItem`?

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

Problem

I have two classes like that: ``` public class Order{ private Integer id; private List<Position> positions; ... } public class Position{ private Integer id; private String content; ... } ``` Now, I have a list with orders and want to get all orders that have positions with a specific content. At the moment i do it like that: ``` 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 do that with lambdaj? Thanks in advance.

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