FreeMarker automatically scans all JAR files in your WEB-INF/lib directory. If it finds .tld files inside a JAR's META-INF directory, like your META-INF/mytaglib.tld, it will peek inside it in order to find the<uri>
tag. If it finds one, it will make the taglib available via this URI, e.g a taglib defined like
<taglib>
<shortname>my custom taglib</shortname>
<uri>http://example.org/mytaglib</uri>
<!-- ... --></taglib>
can be used in FreeMarker via
<#assign my=JspTaglibs["http://example.org/mytaglib"] />