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    <h1 class="title">Antlib Class Loaders</h1>
            <h3 class="section">
      <a name="Jose Alberto Fernandez"></a>
      Jose Alberto Fernandez
    </h3>
                        <p>
 Let me first say that this feature appeared by the need to be able to say,
 </p>
                                <pre class="code">
&lt;antlib name=&quot;A&quot; classpathref=&quot;XYZ&quot;/&gt;
&lt;antlib name=&quot;B&quot; classpathref=&quot;XYZ&quot;/&gt;
</pre>
                                <p>
 And being able to make sure that B and A use the same classLoader
 and therefore they can use each other components.
</p>
                                <p>

 My solution at the time was this idea of a named classloader that
 you could define using a classpath, and then tell your antlibs use
 this or that classloader, if you use the same classloader visibility
 is guaranteed.
</p>
                        <h3 class="section">
      <a name="Stefan Bodewig 23.04.2003 17:11"></a>
      Stefan Bodewig 23.04.2003 17:11
    </h3>
                        <p>

I understand that usecase (using the same class loader for 2 different antlibs) 
and think it's important.  See Steve
Loughran's comment on the .NET tasks wanting to have access to the
datatypes defined in the cpptasks project for example.
</p>
                                <p>

Take a look at what Costin had done to &lt;taskdef&gt; and &lt;typedef&gt; with
the loaderref attribute.  This has now (i.e. CVS HEAD) been
generalized in ClasspathUtils, the infrastructure for named
classloaders is there - at least the foundation for it.
</p>
                                <p>

Stefan
</p>
                        <h3 class="section">
      <a name="Costin Manolache 29.04.2003 18:52"></a>
      Costin Manolache 29.04.2003 18:52
    </h3>
                        <p>
The main issue is how to enforce ordering to deal with dependencies
between the antlibs.
</p>
                                <p>
Or simply do not deal with dependencies, ie antlibs must not (yet)
depend on on the other, except for the core ones.
</p>
                                <p>
Using an unified class loader ( at least as default ) - like jboss is doing,
or like JMX loading policy  - has a lot of benefits.  It also has some cases
that are not well covered - so we'll probably need to deal with both
"unified loader" and "loader hierarchy" cases.
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