<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns:MadCap="http://www.madcapsoftware.com/Schemas/MadCap.xsd" MadCap:lastBlockDepth="2" MadCap:lastHeight="120" MadCap:lastWidth="624" MadCap:disableMasterStylesheet="true" MadCap:tocPath="Advanced Features" MadCap:InPreviewMode="false" MadCap:RuntimeFileType="Topic" MadCap:TargetType="WebHelp" MadCap:PathToHelpSystem="../../" MadCap:HelpSystemFileName="index.xml" MadCap:SearchType="Stem">
<head><title>Enhancement Tools</title>
<script type="text/javascript">/* <![CDATA[ */
window.onload = function(){
var pathToFlash = $('html').attr('MadCap:PathToHelpSystem') + 'Content/Resources/Code/ZeroClipboard.swf';
ZeroClipboard.setMoviePath(pathToFlash);
function bindToClipBord(element,content){
var clip = new ZeroClipboard.Client();
clip.setText(content);
clip.glue(element);
};
if(location.protocol==='file:'){
$('.copylink-marker').remove();
} else{
$('.copylink-marker').each(function(){
var text = $(this).parent().parent().children('.prettyprint').html();
$(this).hover(function(){
bindToClipBord(this,text);
},
function(){});
});
}
prettyPrint();
};
/* ]]> */</script>
<link href="../SkinSupport/MadCap.css" rel="stylesheet" />
<link href="../Resources/Stylesheets/OnlineStyle.css" rel="stylesheet" />
<script src="../SkinSupport/MadCapAll.js">
</script>
<script src="../Resources/Code/prettify.js">
</script>
<script src="../Resources/Code/lang-vb.js">
</script>
<script src="../Resources/Code/jquery.min.js">
</script>
<script src="../Resources/Code/ZeroClipboard.js">
</script>
</head>
<body>
<p class="MCWebHelpFramesetLink" style="display: none;"><a href="../../index_CSH.html#advanced_topics/enhancement_tools.htm" style="">Open topic with navigation</a>
</p>
<div class="MCBreadcrumbsBox"><span class="MCBreadcrumbsPrefix">You are here: </span><a class="MCBreadcrumbsLink" href="../advanced_topics.htm">Advanced Features</a><span class="MCBreadcrumbsDivider"> > </span><span class="MCBreadcrumbs">Enhancement Tools</span>
</div>
<p>
<script type="text/javascript">/*<![CDATA[*/document.write('<a href="' + location.href +'">');
document.write("Direct Link");
document.write('</a>');/*]]>*/</script>
</p>
<p>
</p>
<h1><a name="kanchor77"></a>Enhancement Tools</h1>
<p>Enhancement tools provide a convenient framework for application (jar, dll, exe) or classes modification to support db4o-specific functionality. Enhancement tools can work on a ready application or library and apply the improvements at load or build time. </p>
<p>The tools functionality is provided through <span class="PrimaryByteCode">bytecode</span> instrumentation. This process inserts special, usually
short, sequences of <span class="PrimaryByteCode">bytecode</span> at designated points in your code. It is
typically used for profiling or monitoring, however the range of use of
<span class="PrimaryByteCode">bytecode</span> instrumentation is not limited by this tasks: it can be applied
anywhere where a specific functionality should be plugged into the ready built
classes.</p>
<p>db4o Enhancement Tools currently have these cases for <span class="PrimaryByteCode">bytecode</span>instrumentation:</p>
<ul>
<li value="1"><a href="../basics/activation_concept/transparent_activation_framework.htm">Transparent
Activation</a>
</li>
<li value="2"><a href="../basics/update_concept/transparent_persistence.htm">Transparent Persistence</a>
</li>
<li value="3"><a href="../basics/querying/native_queries/native_query_optimization.htm">Native Query Optimization </a>
</li>
</ul>
<p>In <a href="../basics/update_concept/transparent_persistence.htm">transparent activation/persistence case</a>, classes are required
to implement <span class="PrimaryActivatable">IActivatable</span> interface to support transparent activation. In many
cases you don't want to pollute your classes with some additional
interface, or even won't be able to do so if you use a third party classes
library. That's where bytecode instrumentation comes handy: <span class="PrimaryActivatable">IActivatable</span>interface will be implemented
on your existing classes by applying bytecode instrumentation. Another
advantage of this approach - you can still work on your "clean" classes, just
do not forget to run the instrumentation afterwards.</p>
<p>In the native query optimization case bytecode
instrumentation is used as a more performant alternative to a run-time
optimization. When an native query is optimized the user and compiler-friendly syntax of
<span class="MCTextPopup"><a href="javascript:void(0);" class="MCTextPopupSpot" onclick="FMCTextPopup( event, this ); return false;">NQ<img style="border: none;margin-left: 5px;" src="../SkinSupport/ExpandingClosed.gif" MadCap:altsrc="../SkinSupport/ExpandingOpen.gif" class="MCExpandingIcon" onload="if ( typeof( FMCPreloadImage ) == 'function' ) { FMCPreloadImage( '../SkinSupport/ExpandingOpen.gif' ); }" /></a><span class="MCTextPopupBody" style="display: none; ">Native Query</span></span> predicate is replaced with a query-processor-friendly code. Obviously, optimization process can take some time, therefore it
can be a good choice to use pre-instrumented classes, then to let the
optimization be executed each time it is required by application.</p>
<p>
<p>The instrumentation can be run at build time, also known as static
instrumentation. In this case a special build script calls runs the instrumentation on the classes
before packaging them to <span class="PrimaryArtefact">assembly</span>, or on the <span class="PrimaryArtefact">assembly</span> itself. This is the fastest solution as no time is
spent on bytecode instrumentation at runtime. </p>
</p>
<p>There are different possibilities to integrate the enhancement tools into a project.</p>
<ul>
<li value="1">It's possible to integrate the enhancement step into the build process by using a <span class="PrimaryAnt">MSBuild</span>-task. <a href="enhancement_tools/build_time_enhancement.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Build Time Enhancement Example"</a></li>
<li MadCap:conditions="Primary..NET" value="2">It's possible to use the Db4oTool directly from the command-line. <a href="enhancement_tools/enhancement_for_.net/db4otool.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Db4oTool"</a></li>
</ul>
<script type="text/javascript" src="../SkinSupport/MadCapBodyEnd.js">
</script>
</body>
</html>
