@Override
	public void setResourceLoader(ResourceLoader resourceLoader) {
		this.resourceLoader = (ResourcePatternResolver) resourceLoader;
	}
Will parse the module xml definition file, looking for "${foo}" placeholders and advertise a {@link ModuleOption}
for each of those.

Note that this may end up in false positives and does not convey much information.
spring-xd-module/src/main/java/org/springframework/xd/module/options/DefaultModuleOptionsMetadataResolver.java