I'd built a simple app which uses Spring Data 3.1.0.RELEASE and Eclipselink 2.4 on the server side - which is hosted in the Tomcat 7.0.27. In mywebapp/META-INF/context.xml I have Spring classloader
<Loader loaderClass="org.springframework.instrument.classloading.tomcat.TomcatInstrumentableClassLoader"/>
If I put spring-instrument-tomcat.jar into $TOMCAT_HOME/lib then Tomcat runs mywebapp well but if I put spring-instrument-tomcat.jar into the $TOMCAT_HOME/webapps/mywebapp/WEB-INF/lib - Tomcat dies with exception
java.lang.IllegalStateException: ClassLoader [org.apache.catalina.loader.WebappClassLoader] does NOT provide an 'addTransformer(ClassFileTransformer)' method. Specify a custom LoadTimeWeaver or start your Java virtual machine with Spring's agent: -javaagent:org.springframework.instrument.jar
Context loader parameter useSystemClassLoaderAsParent set to false does not help either.
I don't want to have any (custom) global lib in Tomcat (and it won't be easy to have the global one in our real-life production system) thus I'm trying to localize all the needed stuff in simple (yet big) war file. Any thoughts on how to achieve such encapsulation?
Well, if you do not want extra jars in Tomcat's lib folder, the only option (to still have Spring / AspectJ LTW work) is to edit the tomcat's run script to add -javaagent:...instrument.jar to its JAVA_OPTS or CATALINA_OPTS, and remove the context.xml file (you won't need TomcatInstrumentableClassLoader anymore).