Avoid this for loop with Lambdaj

Question

How can avoid this loop with lambdaj, I want to add all elements from List personas into another list

String tipo = "type_1";
for (Person person : personas) {
    lista.add(new SimpleResultForm(tipo, person));
}

I'm using Java 7 so, Java 8 lambda expresions won't work, I need a solution arround Lambdaj library

http://howtodoinjava.com/core-java/collections/java-8-tutorial-streams-by-examples/ — Anand Vaidya, Apr 05 '16 at 08:19

score 0 · Answer 1 · answered Apr 05 '16 at 08:24

With java 8:

String tipo = "type_1";
lista = personas.stream()
             .map(person -> new SimpleResultForm(tipo, person))
             .collect(Collectors.toList());

And in case lista already contains data:

String tipo = "type_1";
lista.addAll(personas.stream()
             .map(person -> new SimpleResultForm(tipo, person))
             .collect(Collectors.toList()));

Felix Ng · Answer 2 · 2016-04-05T13:21:10.443

-1

In Java 8, assume you had already created the list "lista", then this one-liner should do the work.

String tipo = "type_1";
personas.stream().forEach(e -> lista.add(new SimpleResultForm(tipo, e)));

edited Apr 05 '16 at 13:21

answered Apr 05 '16 at 11:20

Felix Ng

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While this code may answer the question, providing additional context regarding _why_ and/or _how_ it answers the question would significantly improve its long-term value. Please [edit] your answer to add some explanation. – Toby Speight Apr 05 '16 at 11:46

Avoid this for loop with Lambdaj

2 Answers2