Author: oheger
Date: Thu Nov 19 21:28:23 2015
New Revision: 1715285
URL: http://svn.apache.org/viewvc?rev=1715285&view=rev
Log:
[CONFIGURATION-610] Improvements of user guide.
Described some more corner cases of variable interpolation.
Modified:
commons/proper/configuration/trunk/src/site/xdoc/userguide/howto_basicfeatures.xml
Modified:
commons/proper/configuration/trunk/src/site/xdoc/userguide/howto_basicfeatures.xml
URL:
http://svn.apache.org/viewvc/commons/proper/configuration/trunk/src/site/xdoc/userguide/howto_basicfeatures.xml?rev=1715285&r1=1715284&r2=1715285&view=diff
==============================================================================
---
commons/proper/configuration/trunk/src/site/xdoc/userguide/howto_basicfeatures.xml
(original)
+++
commons/proper/configuration/trunk/src/site/xdoc/userguide/howto_basicfeatures.xml
Thu Nov 19 21:28:23 2015
@@ -238,9 +238,25 @@ action.key = ${const:java.awt.event.KeyE
java.home = ${env:JAVA_HOME}
]]></source>
<p>
- If a variable cannot be resolved, e.g. because the name is invalid or an
- unknown prefix is used, it won't be replaced, but is returned as is
- including the dollar sign and the curly braces.
+ Below is some more information related to variable interpolation users
+ should be aware of:
+ <ul>
+ <li>If a variable cannot be resolved, e.g. because the name is invalid
+ or an unknown prefix is used, it won't be replaced, but is returned as
+ is including the dollar sign and the curly braces.</li>
+ <li>References to variables can be nested; a variable can refer to a
+ variable which in turn can have references to other variables and so
+ on.</li>
+ <li>Cyclic references are detected. In this case, no interpolation is
+ done.</li>
+ <li>Variable interpolation happens when properties are queried from the
+ configuration, not at creation time. Therefore, the mechanism is quite
+ dynamic: changes on one property can impact the value of another
+ property that references the first one.</li>
+ <li>Variable interpolation is done by all property access methods. One
+ exception is the generic <code>getProperty()</code> method which
+ returns the raw property value.</li>
+ </ul>
</p>
</subsection>
