themes/lucene/templates/lucene/core/documentation.html

{% extends "lucene/core/page.html" %}

{% block content %}
<div>
  {{ super() }}
  <h2>Java Docs</h2>
  <ul>
    <li><a href="{{ SITEURL }}/core/{{ LUCENE_LATEST_RELEASE | replace(".", "_") }}/index.html">{{ LUCENE_LATEST_RELEASE }}</a></li>
    <li><a href="{{ SITEURL }}/core/{{ LUCENE_PREVIOUS_MAJOR_RELEASE | replace(".", "_") }}/index.html">{{ LUCENE_PREVIOUS_MAJOR_RELEASE }}</a></li>
  </ul>
</div>
{% endblock %}