com.gf.components.reflections.ReflectionsScanner.java Source code

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Here is the source code for com.gf.components.reflections.ReflectionsScanner.java

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/*
 * Copyright 2012 Evgeny Dolganov (evgenij.dolganov@gmail.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.
 */
package com.gf.components.reflections;

import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import org.reflections.Reflections;
import org.reflections.scanners.SubTypesScanner;
import org.reflections.util.ClasspathHelper;
import org.reflections.util.ConfigurationBuilder;
import org.reflections.util.FilterBuilder;
import org.reflections.vfs.Vfs;

import com.gf.extra.scan.ClassScanner;
import com.gf.log.Log;
import com.gf.log.LogFactory;
import com.google.common.collect.Multimap;

/**
 * Class scanner implementation.
 * Use it for JBoss AS for example.
 * <p>For using this component you need this additional libraries (include them into CLASSPATH):
 * <ul>
 *     <li><a href='http://code.google.com/p/reflections/'>Reflections</a></li>
 *   <li><a href='http://code.google.com/p/guava-libraries/'>The Guava project</a></li>
 *   <li><a href='http://www.csg.ci.i.u-tokyo.ac.jp/~chiba/javassist/'>Javassist</a></li>
 * </ul>
 * @author Evgeny Dolganov
 *
 */
public class ReflectionsScanner implements ClassScanner {

    static {
        Vfs.addDefaultURLTypes(new JBossVFSUrlType());
    }

    Log log = LogFactory.getLog(getClass());

    public Set<Class<?>> getClasses(String packageRoot, Class<?> parentClass) {

        SubTypesScanner subTypesScanner = new SubTypesScanner();

        new Reflections(new ConfigurationBuilder()
                .filterInputsBy(new FilterBuilder().include(FilterBuilder.prefix(packageRoot)))
                .setUrls(ClasspathHelper.forPackage(packageRoot)).setScanners(subTypesScanner));

        Multimap<String, String> map = subTypesScanner.getStore();
        Set<Class<?>> out = findAbsoluteSubTypes(map, parentClass);
        return out;
    }

    private Set<Class<?>> findAbsoluteSubTypes(Multimap<String, String> map, Class<?> parentClass) {

        HashSet<Class<?>> out = new HashSet<Class<?>>();
        HashSet<String> processed = new HashSet<String>();

        Collection<String> values = map.values();
        for (String candidat : values) {
            if (processed.contains(candidat)) {
                continue;
            }
            try {
                Class<?> clazz = Class.forName(candidat);
                if (parentClass.isAssignableFrom(clazz)) {
                    out.add(clazz);
                }
            } catch (ClassNotFoundException e) {
                log.error("can't get class by name " + candidat, e);
            }
            processed.add(candidat);
        }
        return out;
    }

}