找到指定包名下的所有class

package test;

import java.io.IOException;
import java.util.LinkedHashSet;
import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.type.classreading.CachingMetadataReaderFactory;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.util.ClassUtils;

public class FindTargetPackageClass {
    private static Log logger = LogFactory.getLog(FindTargetPackageClass.class);
    protected static final String DEFAULT_RESOURCE_PATTERN = "**/*.class";

    private ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();

    private MetadataReaderFactory metadataReaderFactory = new CachingMetadataReaderFactory(
            this.resourcePatternResolver);

    private String resourcePattern = DEFAULT_RESOURCE_PATTERN;

    public static void main(String[] args) throws Exception {
        FindTargetPackageClass test = new FindTargetPackageClass();
        System.out.println(test.findTargetClassNames("org.springframework.context.event"));
    }
    public Set<String> findTargetClassNames(String basePackage) {
        Set<String> candidates = new LinkedHashSet<String>();
        try {
            String packageSearchPath = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX
                    + ClassUtils.convertClassNameToResourcePath(basePackage)
                    + "/" + this.resourcePattern;
            Resource[] resources = this.resourcePatternResolver
                    .getResources(packageSearchPath);
            for (int i = 0; i < resources.length; i++) {
                Resource resource = resources[i];
                MetadataReader metadataReader = this.metadataReaderFactory
                        .getMetadataReader(resource);
                String clazzName = metadataReader.getClassMetadata().getClassName();
                candidates
                        .add(clazzName);
                logger.debug("Find Class " + clazzName);
            }
        } catch (IOException ex) {
            throw new BeanDefinitionStoreException(
                    "I/O failure during classpath scanning", ex);
        }
        return candidates;
    }
}