Bug 562908 - Populate the JustJ Git clones with initial content
Add documentation about jdeps.
diff --git a/content/documentation.php b/content/documentation.php
index e2d1523..7cebce3 100644
--- a/content/documentation.php
+++ b/content/documentation.php
@@ -13,7 +13,7 @@
<div id="midcolumn">
<h1><img style="height: 2ex;" src="justj_title.svg" alt="Eclipse JustJ"/> Documentation</h1>
-<h2 id="jre-gen-anatomy">The Anatomy of <code><a href="https://ci.eclipse.org/justj/job/build-jres/lastSuccessfulBuild/artifact/jre-gen/">jre-gen</a></code></h2>
+<h2 id="jre-gen-anatomy">Anatomy of <code><a href="https://ci.eclipse.org/justj/job/build-jres/lastSuccessfulBuild/artifact/jre-gen/">jre-gen</a></code></h2>
<p>
As described in the <a href="?page=index#jre-p2">Automated JRE p2 Generation with <img src="justj_title.svg" atl="justj" style="height: 2ex;"/>.tools</a> section of the main page,
the generation of a JRE p2 repository is fully automated,
@@ -241,4 +241,46 @@
<!-- ############################# THE SECTION ABOVE IS GENERATED BY org.eclipse.justj.codegen.model.util.Generator -Dorg.eclipse.justj.describe=true ################################### -->
+<h2 id="jdeps">Building Smaller JREs with <code>jdeps</code></h2>
+
+<p>
+Java's modularized architecture supports analyzing a jar's module dependencies using <code><a href="https://docs.oracle.com/en/java/javase/14/docs/specs/man/jdeps.html">jdeps</a></code>.
+With such an analysis it is possible to determine the reduced dependencies of a particular IDE or RCP distribution.
+JustJ has automated this dependency analysis via the <code><a href="https://ci.eclipse.org/justj/job/build-jdeps/">build-jres</a></code> job
+which generates <a href="https://download.eclipse.org/justj/jdeps/">a detailed report</a>.
+</p>
+<p>
+Reducing the JRE size is particularly important for smaller applications such as the <a href="https://wiki.eclipse.org/Eclipse_Installer">Eclipse Installer</a>
+which is currently roughly 53MB in size.
+Shipping that with a 70MB JRE would be a significant bloat.
+Furthermore, most users treat it as disposable, repeatedly downloading a new one with each release.
+It is downloaded roughy 3 million times per release cycle.
+</p>
+<p>
+The <a href="https://www.eclipse.org/downloads/packages/">EPP Packages</a> range from 155MB to 400MB in size.
+For this use case, size is much less of a concern.
+In addition, the majority of the users install using the installer rather than downloading EPP Packages.
+This has the advantage that the JRE large fragment will be in the shared bundle pool by default and can be reused shared among multiple installions and needs to be updated only whether there is a new Java release.
+</p>
+<p>
+The result of this analysis is used to produce the JREs with <code>.minimal</code> qualifier on the download site:
+</p>
+<blockquote>
+<a href="https://download.eclipse.org/justj/sandbox/jres/14/downloads/latest/">https://download.eclipse.org/justj/sandbox/jres/14/downloads/latest/</a>
+</blockquote>
+<p>
+The <code>.stripped</code> versions of these are less than 1/2 the size of the corresponding <code>.full.stripped</code> version.
+</p>
+<p>
+Some outstanding concerns that remain are of course the impact of what's excluded.
+For example, if certain agents, e.g., <code>jdk.hotspot.agent</code>, or <code>jdk.jdwp.agent</code> are excluded, it will not be possible to use such a JRE for debugging.
+Of course stripping also makes the JRE poor for debugging purposes and could lead to less informative stack traces.
+The absence of the <code>jdk.localedata</code> module might also be a concern.
+</p>
+
+<p>
+Community feedback is welcome. Please use <a href="https://bugs.eclipse.org/bugs/show_bug.cgi?id=562908">Bug 562908</a> for this purpose.
+</p>
+
+
</div>
diff --git a/content/en_index.php b/content/en_index.php
index 2315b74..0b95ed4 100644
--- a/content/en_index.php
+++ b/content/en_index.php
@@ -98,6 +98,7 @@
You will see there that a full, compressed JRE, i.e., those JREs with the <code>.jre.full</code> qualifier, are roughly 70MB is size,
while an absolutely minimal, compressed, OSGi-capable JRE, i.e., those JREs with the <code>.jre.base</code> qualifier, are roughly 20MB is size.
These sizes are significantly (15% to 20%) reduced by stripping debug information, i.e., those JREs with the <code>.stripped</code> qualifier.
+See the <a href="?page=documentation#jdeps">Building Smaller JREs with <code>jdeps</code></a> section for details about creating JREs with a subset of the available modules.
<p>
<p>
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index c8661cc..1464fec 100644
--- a/index.php
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@@ -196,6 +196,10 @@
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+blockquote {
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+
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