Appendix B. Migrating to Spring Framework 3.1

In this appendix we discuss what users will want to know when upgrading to Spring Framework 3.1. For a general overview of features, please see Chapter 3, New Features and Enhancements in Spring 3.1

B.1 Component scanning against the "org" base package

Spring Framework 3.1 introduces a number of @Configuration classes such as org.springframework.cache.annotation.ProxyCachingConfiguration and org.springframework.scheduling.annotation.ProxyAsyncConfiguration. Because @Configuration is ultimately meta-annotated with Spring's @Component annotation, these classes will inadvertently be scanned and processed by the container for any component-scanning directive against the unqualified "org" package, e.g.:

        <context:component-scan base-package="org"/>

Therefore, in order to avoid errors like the one reported in SPR-9843, any such directives should be updated to at least one more level of qualification e.g.:

      <context:component-scan base-package=""/>

Alternatively, an exclude-filter may be used. See context:component-scan documentation for details.