Example for iterating over a Map of Collections using the Pebble Java templating library

Output

    <h2>2001</h2>
            <p>A Space Odyssey</p>
        <h2>1990</h2>
            <p>1990-1</p>
            <p>1990-2</p>
    

Test.java

import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.mitchellbosecke.pebble.PebbleEngine;
import com.mitchellbosecke.pebble.template.PebbleTemplate;

public class Test {

	// Example for: https://github.com/mbosecke/pebble/issues/55
	public static void main(String args[]) throws Exception {
		Map<Integer, List<Article>> articles = new HashMap<>();	// <year, article>
		articles.put(1990, Arrays.asList(new Article[] {new Article("1990-1"), new Article("1990-2")}));
		articles.put(2001, Arrays.asList(new Article[] {new Article("A Space Odyssey")}));

		Map<String, Object> context = new HashMap<>();
		context.put("articles", articles);
		
		Writer writer = new StringWriter();
		PebbleTemplate compiledTemplate = (new PebbleEngine()).getTemplate("test.peb");
		compiledTemplate.evaluate(writer, context);

		System.out.println(writer.toString());
	}

}

class Article {
	final String title;

	public Article(String title) {
		this.title = title;
	}

	public String getTitle() {
		return title;
	}

}

test.peb

{% for entry in articles %}
    <h2>{{ entry.key }}</h2>
    {% for article in entry.value %}
        <p>{{ article.title }}</p>
    {% endfor %}
{% endfor %}

articles.entrySet is not working. Replaced with articles