SHL-23 - Create docbook based reference guide

docs/src/reference/docbook/preface.xml

@@ -1,6 +1,63 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<preface xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="preface">
+<preface version="5.0" xml:id="preface" xmlns="http://docbook.org/ns/docbook"
+         xmlns:ns5="http://www.w3.org/2000/svg"
+         xmlns:ns4="http://www.w3.org/1999/xhtml"
+         xmlns:ns3="http://www.w3.org/1998/Math/MathML"
+         xmlns:ns2="http://www.w3.org/1999/xlink"
+         xmlns:ns="http://docbook.org/ns/docbook">
   <title>Preface</title>
 
-  <para></para>
+  <para>The Spring Shell provides an interactive shell that allows you to
+  plugin your own custom commands using a Spring based POJO programming
+  model.</para>
+
+  <para>The shell has been extracted from the Spring Roo project, giving it a
+  strong foundation and rich feature set. One significant change from Spring
+  Roo is that the plugin model is no longer based on OSGi but instead uses
+  Spring IoC container to discover commands through classpath scanning. There
+  is currently no classloader isolation between plugins, however that maybe
+  added in future versions.</para>
+
+  <para>Spring Shell's features include</para>
+
+  <itemizedlist>
+    <listitem>
+      <para>A POJO based programming model to contribute custom
+      commands</para>
+    </listitem>
+
+    <listitem>
+      <para>Use Spring's classpath scanning functionality as a basis for a
+      command plugin strategy</para>
+    </listitem>
+
+    <listitem>
+      <para>Inheritance of the <link
+      ns2:href="http://static.springsource.org/spring-roo/reference/html-single/index.html#usage-shell">Roo
+      Shell features</link></para>
+    </listitem>
+
+    <listitem>
+      <para>Tab completion</para>
+    </listitem>
+
+    <listitem>
+      <para>Scripting and Script recording</para>
+    </listitem>
+
+    <listitem>
+      <para>Customize command prompt, banner, shell history file name.</para>
+    </listitem>
+  </itemizedlist>
+
+  <para>This document assumes that the reader already has a basic familiarity
+  with the Spring Framework.</para>
+
+  <para>While every effort has been made to ensure that this documentation is
+  comprehensive and there are no errors, nevertheless some topics might
+  require more explanation and some typos might have crept in. If you do spot
+  any mistakes or even more serious errors and you can spare a few cycles
+  during lunch, please do bring the error to the attention of the Spring Shell
+  team by <link ns2:href="https://jira.springsource.org/browse/SHL">raising an
+  issue</link>.</para>
 </preface>