Java8 Transform list of object to list of one attribute of object

Question

I want to use Java 8 tricks to do the following in one line.

Given this object definition:

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
pub         


        

Answer 1

This should do the trick:

objects.stream().map(MyObj::getId).collect(Collectors.toList());

that said, the method reference :: operator allows you to reference any method in your classpath and use it as a lambda for the operation that you need.

As mentioned in the comments, a stream preserves order.