Occasionally problems may be encountered with classes that have been load-time woven. Symptoms will include incorrect program function or a Java exception such as java.lang.VerifyError. Problems can be caused by the way an aspect or class is built, incompatibilities between AspectJ and generated byte-code e.g. CGLIB or a bug in the weaver. When these problems occur it may be necessary to attach the class files concerned to a bug report. AspectJ can be configured to dump byte-code to disk using META-INF/aop.xml. The _ajdump subdirectory the the current working directory is used. See the Development Environment Guide for details of how to configure byte-code dumping. By default AspectJ will dump byte-code only after it is woven. This is because usually the original class file is already available. However byte-code is sometimes generated by frameworks or downloaded over the network in which case AsepctJ can dump the byte-code before it is woven too. The following META-INF/aop.xml will weave classes in the com.foo package (and subpackages) but not CGLIB generated classes in the com.foo.bar package (and subpackages). It will also ensure all woven byte-code is dumped both before and after weaving. ]]> You should see messages similar to this: On disk you would find the following files: