Details
Major Description
The initialization fails entirely due to what appears to be a problem
configuring the logsystem. I found a single reference to someone else
encountering this problem in the Google cache at the URL listed above
(http://216.239.37.104/search?q=cache:swlDhCygFHoJ:www.disastertravel.com/computers/java/velocity/example_servlet.php+velocity+java.lang.ClassCastException:+%27cache%27+doesn%27t+map+to+a+Boolean+object&hl=en&ie=UTF-8)
In our case, the error occurs when initializing the standalone Velocity parser
with the following code:
Velocity.setProperty(RuntimeConstants.RUNTIME_LOG_LOGSYSTEM_CLASS,
"org.apache.velocity.runtime.log.SimpleLog4JLogSystem");
Velocity.setProperty("runtime.log.logsystem.log4j.category", "velocity");
Velocity.init();
The "velocity" category is configured in the log4j_conf.xml file as:
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
<appender name="velocity_app" class="org.apache.log4j.FileAppender">
<param name="File"
value="/www/sites/tomcat/webapps/nndc/logs/idb_velocity.log" />
<param name="Append" value="true" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%t %-5p %c
- %m%n"/>
</layout>
</appender>
<category name="velocity">
<priority value="warn" />
<appender-ref ref="velocity_app" />
</category>
<!-- Root & other categories snipped -->
</log4j:configuration>
Stack trace:
java.lang.ClassCastException: 'cache' doesn't map to a Boolean object
at org.apache.commons.collections.ExtendedProperties.getBoolean(Unknown Source)
at org.apache.commons.collections.ExtendedProperties.getBoolean(Unknown Source)
at
org.apache.velocity.runtime.resource.loader.ResourceLoader.commonInit(ResourceLoader.java:116)
at
org.apache.velocity.runtime.resource.ResourceManagerImpl.initialize(ResourceManagerImpl.java:186)
at
org.apache.velocity.runtime.RuntimeInstance.initializeResourceManager(RuntimeInstance.java:502)
at org.apache.velocity.runtime.RuntimeInstance.init(RuntimeInstance.java:268)
at org.apache.velocity.runtime.RuntimeSingleton.init(RuntimeSingleton.java:169)
at org.apache.velocity.app.Velocity.init(Velocity.java:123)
at gov.noaa.nndc.idb.IdbTemplateParser.initVelocity(IdbTemplateParser.java:145)
The handling of configuring the logsystem needs to be improved such that this is
not a fatal error. However, this bug may be somewhat difficult to pin down as I
am unable to reproduce the problem on my local system, but it occurs in the
remote deployment. In any case, I suspect it to be related to problems writing
the logfiles in the designated place that starts the chain of events that
results in the (seemingly unrelated) error.