Freemarker Servlet - Failed to load template from classpath: ftl resource on Windows

Exception failing to load Freemarker template was found on WebLogic 12c/Windows environment.

Exception:

==========================

<May 21, 2014 2:46:46 PM EDT> <Error> <HTTP> <BEA-101005> <[ServletContext@1404590421[app:hippo-intranet module:/site path:null spec-version:3.0]] getRealPath() called with unsafe path: "/classpath:/org/hippoecm/hst/pagecomposer/builtin/components/vbox.ftl".
java.io.IOException: The filename, directory name, or volume label syntax is incorrect
at java.io.WinNTFileSystem.canonicalize0(Native Method)
at java.io.Win32FileSystem.canonicalize(Win32FileSystem.java:414)
at java.io.File.getCanonicalPath(File.java:618)
at weblogic.servlet.internal.WebAppServletContext.getRealPath(WebAppServ
letContext.java:678)
at freemarker.cache.WebappTemplateLoader.findTemplateSource(WebappTempla
teLoader.java:129)
Truncated. see log file for complete stacktrace

==========================

HstFreemarkerServlet uses freemarker.cache.MultiTemplateLoader which delegate call to the internal template loaders: 1) WebappTemplateLoader, 2) HstClassTemplateLoader, and 3) RepositoryTemplateLoader.

MultiTemplateLoader doesn't catch any IOException other than FileNotFoundException. As a result, if WebappTemplateLoader throws an exception like excerpted above ("java.io.IOException: The filename, directory name, or volume label syntax is incorrect"), then MultiTemplateLoader doesn't try to load the template from the remaining template loaders.

By the way, I've tested the following code in a jsp on non-Windows system:

<%
String path = "/classpath:/org/hippoecm/hst/pagecomposer/builtin/components/vbox.ftl";
String realPath = application.getRealPath(path);
out.println("realPath: " + realPath);
%>

It prints out the following on non-Windows environment without any problem:

realPath: /home/woonsan/myhippoproject/target/tomcat6x/webapps/site/classpath:/org/hippoecm/hst/pagecomposer/builtin/components/vbox.ftl

So, this problem seems to be a Window environment specific issue when processing with "classpath:" prefixed freemarker templates.

Also, based on the stack trace, WebLogic seems to invoke java.io.File.getCanonicalPath() in ServletContext.getRealPath(), which might be a difference from the Tomcat's behavior. (That's probably why we cannot observe this problem on Tomcat/Windows environment.)