Include specific JAR files in skinny WARs with Maven - maven

Question

I've been having some problems with a WAR module and its difficulty in loading a taglib. I kept getting this exception:
JSPG0047E: Unable to locate tag library for uri http://www.springframework.org/tags/form
at com.ibm.ws.jsp.translator.visitor.tagfiledep.TagFileDependencyVisitor.visitCustomTagStart(TagFileDependencyVisitor.java:76)
at com.ibm.ws.jsp.translator.visitor.JspVisitor.processJspElement(JspVisitor.java:366)
at com.ibm.ws.jsp.translator.visitor.JspVisitor.processChildren(JspVisitor.java:419)
at com.ibm.ws.jsp.translator.visitor.JspVisitor.processJspElement(JspVisitor.java:369)
...
After a bit of searching, I found a lot of suggestions that the spring jars need to be on the application's classpath. I checked in my EAR's lib folder and sure enough, spring-web and spring-webmvc were there.
It should be noted that the EAR is built with skinny WARs - since they use most of the same libraries, all library files are in MyAppEAR/lib instead of MyAppEAR/MyWAR1/WEB-INF/lib, MyAppEAR/MyWAR2/WEB-INF/lib, MyAppEAR/MyWAR3/WEB-INF/lib, etc...
I did finally manage to resolve this missing taglib error, but I had to move spring-web and spring-webmvc to MyAppEAR/MyWAR1/WEB-INF/lib.
So I have a couple of questions:
Is this the only way to fix this problem?
If so, how can I build a sort-of skinny WAR using maven? Currently, the EAR part of the POM looks like this:
<plugin>
<artifactId>maven-ear-plugin</artifactId>
<version>2.8</version>
<configuration>
<applicationName>MyAppEAR</applicationName>
<defaultLibBundleDir>lib</defaultLibBundleDir>
<skinnyWars>true</skinnyWars>
I guess I could turn off skinny WARs and then have some other step remove all libraries from the WAR files and copy them to MyAppEAR/lib except for the spring web jars, but I am hoping there's a better solution.

Answer 1

I had the same issues myself - I just couldn't access Spring or Sitemesh's TLDs when my spring JAR files were in my ear/lib folder!
Including the classpath in the MANIFEST was causing my app server go haywire (since all dependencies were being loaded twice).
(Yes, I also have skinnyWars set to true in my maven-ear-plugin).
The only way I could have gone round the issue was by including Spring and sitemesh by including them in maven-war-plugin's configuration:
<packagingExcludes>%regex[WEB-INF/lib/(?!spring|sitemesh).*.jar]</packagingExcludes>
Not the most elegant solution, but the least damaging I could find.
This is my full configuration:
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>2.1.1</version>
<configuration>
<!--
Q. Why is this set?
A. maven-ear-plugin in our EAR modules have `skinnyWars` enabled to that WAR files
would not include any third-party libraries in the WAR's WEB-INF/lib folder, however
this does not work for ejbs (like our own EJB modules).
We'll need to exclude them from here anyway (except for a few select JARS)...
-->
<packagingExcludes>%regex[WEB-INF/lib/(?!spring|sitemesh).*.jar]</packagingExcludes>
<archive>
<manifest>
<addClasspath>false</addClasspath>
</manifest>
</archive>
</configuration>
</plugin>
PS. My setup is JBoss EAP 6.x and an ear file with several EJBs, WARs and third-party JARs.

Answer 2

I think I got it working.
In the WAR's POM file:
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>2.2</version>
<configuration>
<warSourceDirectory>src/main/webapp</warSourceDirectory>
<packagingExcludes>WEB-INF/lib/*.jar,WEB-INF/*.xmi</packagingExcludes>
<archive>
<manifest>
<addClasspath>true</addClasspath>
<classpathPrefix>../../WEB-INF/lib/</classpathPrefix>
</manifest>
</archive>
</configuration>
</plugin>
This causes the generated WAR file to have a META-INF/MANIFEST.MF file with classpath entries that look like ../WEB-INF/lib/$someJarFile - that is the relative path from the WAR to the EAR's library folder. I guess the WAR needs to have the classpath specified, having the libraries in the EAR just isn't enough.