package me.prettyprint.hom.annotations;
import java.lang.annotation.Annotation;
import java.util.HashSet;
import java.util.Set;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider;
import org.springframework.core.type.filter.AnnotationTypeFilter;
/**
* Scan for classes annotated with an annotation. The scan starts in the given
* package root so it doesn't need to scan through the entire package structure.
*
* @author Todd Burruss
*/
public class AnnotationScanner {
private static Logger logger = LoggerFactory.getLogger(AnnotationScanner.class);
public Set<Class<?>> scan(String packageRoot, Class<? extends Annotation> anno) {
ClassPathScanningCandidateComponentProvider scanner = new ClassPathScanningCandidateComponentProvider(false);
AnnotationTypeFilter filter = new AnnotationTypeFilter(anno);
scanner.addIncludeFilter(filter);
Set<BeanDefinition> beanSet = scanner.findCandidateComponents(packageRoot);
Set<Class<?>> classSet = new HashSet<Class<?>>();
for (BeanDefinition beanDef : beanSet) {
logger.debug("found candidate bean = " + beanDef.getBeanClassName());
Class<?> clazz;
try {
clazz = Class.forName(beanDef.getBeanClassName());
if (clazz.isAnnotationPresent(anno)) {
logger.debug( "found annotated class, " + clazz.getName());
classSet.add(clazz);
}
}
catch (ClassNotFoundException e) {
logger.error("exception while scanning classpath for annotated classes", e);
}
}
return classSet;
}
}