package Java8_in_Action;

import com.google.common.collect.Lists;

import lombok.AllArgsConstructor;

import lombok.Data;

import java.util.ArrayList;

import java.util.List;

import java.util.Optional;

import java.util.stream.Collectors;

public class StreamAPITest {

public static void main(String[] args) {

List<Article> articles = new ArrayList<>();

articles.add(new Article("title1", "author1", Lists.newArrayList("tag1")));

articles.add(new Article("title2", "author2", Lists.newArrayList("tag1", "Java")));

articles.add(new Article("title3", "author3", Lists.newArrayList("tag1", "Java", "tag3")));

Optional<Article> firstJavaArticle = getFirstJavaArticle(articles);

System.out.println(firstJavaArticle.toString());

List<Article> allJavaArticles = getAllJavaArticles(articles);

System.out.println(allJavaArticles.toString());

}

private static Optional<Article> getFirstJavaArticle(List<Article> articles) {

return articles.stream()

.filter(article -> article.getTags().contains("Java"))

.findFirst();

}

private static List<Article> getAllJavaArticles(List<Article> articles) {

return articles.stream()

.filter(article -> article.getTags().contains("Java"))

.collect(Collectors.toList());

}

@Data

@AllArgsConstructor

private static class Article {

private final String title;

private final String author;

private final List<String> tags;

}

}