org.bitsofinfo.util.reflection.SpringClassFinder.java Source code

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Here is the source code for org.bitsofinfo.util.reflection.SpringClassFinder.java

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/*****************************************************************************
* Copyright 2012  bitsofinfo.g [at] gmail [dot] com 
* 
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* 
* http://www.apache.org/licenses/LICENSE-2.0 
* 
* Unless required by applicable law or agreed to in writing, software 
* distributed under the License is distributed on an "AS IS" BASIS, 
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and 
* limitations under the License
* 
* Author: bitsofinfo.g [at] gmail [dot] com 
* @see bitsofinfo.wordpress.com
*****************************************************************************/
package org.bitsofinfo.util.reflection;

import java.io.File;
import java.io.IOException;
import java.lang.annotation.Annotation;
import java.util.HashSet;
import java.util.Set;

import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.core.type.filter.AnnotationTypeFilter;
import org.springframework.util.ClassUtils;

/**
 * SpringClassFinder is a ClassFinder implementation which leverages the Spring Framework's
 * suite of reflection and resource loading utilities.
 * 
 * @author bitsofinfo.g [at] gmail [dot] com
 *
 */
public class SpringClassFinder implements ClassFinder {

    private static String convertResourceToClassName(Resource resource, String basePackage) throws IOException {
        String path = resource.getURI().toString();
        String pathWithoutSuffix = path.substring(0, path.length() - ClassUtils.CLASS_FILE_SUFFIX.length());
        String relativePathWithoutSuffix = pathWithoutSuffix.substring(pathWithoutSuffix.indexOf(basePackage));
        String className = relativePathWithoutSuffix.replace(File.separator, ".");
        return className;
    }

    @Autowired
    private ResourcePatternResolver resourcePatternResolver;

    @Autowired
    private MetadataReaderFactory metadataReaderFactory;

    public Set<Class> findByTypeAnnotation(Class<? extends Annotation> annotation, String packageRoot)
            throws Exception {

        Set<Class> foundClasses = new HashSet<Class>();

        packageRoot = StringUtils.replace(packageRoot, ".", File.separator);

        AnnotationTypeFilter typeFilter = new AnnotationTypeFilter(annotation);
        String pattern = "classpath*:" + packageRoot + File.separator + "**" + File.separator + "*.class";

        Resource[] resources = resourcePatternResolver.getResources(pattern);

        for (Resource resource : resources) {

            MetadataReader metadataReader = metadataReaderFactory.getMetadataReader(resource);
            if (typeFilter.match(metadataReader, metadataReaderFactory)) {
                String className = convertResourceToClassName(resource, packageRoot);
                foundClasses.add(Class.forName(className));
            }
        }

        return foundClasses;

    }

}