My project uses a simple plugin mechanism based on multiple application contexts defined in plugin jars. However for this to work i have to include all of the plugin jars on the classpath. It would be nice if Spring could automatically load jars and containing components on it's own which are for example placed in the 'plugins' subdirectory of my project.
Is there some solution for this?
I went a bit furtherer and tried to solve this with Jar Class Loader.
Because i'm instantiating the Spring application context manually i can do the following:
GenericApplicationContext ctx = new GenericApplicationContext();
// Load context definitions from plugin jars
JarClassLoader jcl = new JarClassLoader();
jcl.add("plugins/");
XmlBeanDefinitionReader classPathBeansReader = new XmlBeanDefinitionReader(ctx);
classPathBeansReader.setBeanClassLoader(jcl);
classPathBeansReader.setResourceLoader(new PathMatchingResourcePatternResolver(jcl));
classPathBeansReader.loadBeanDefinitions("classpath*:META-INF/my-plugins-*.xml");
However this is not working. From Spring's log i can see that it doesnt read the XML definition in the plugin jar. If i replace the bottom block with
XmlBeanDefinitionReader classPathBeansReader = new XmlBeanDefinitionReader(ctx);
classPathBeansReader.setBeanClassLoader(jcl);
classPathBeansReader.loadBeanDefinitions(new ClassPathResource("META-INF/my-plugins-somemodule.xml",jcl));
it finds and loads the XML definition file and beans from the jar. However this way i'm hardwiring the XML resource name for one plugin, which i don't wan't. How can i make the pattern matching working with JCL?