com.reactive.hzdfs.utils.EntityFinder.java Source code

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Here is the source code for com.reactive.hzdfs.utils.EntityFinder.java

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/* ============================================================================
*
* FILE: EntityFinder.java
*
The MIT License (MIT)
    
Copyright (c) 2016 Sutanu Dalui
    
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
    
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
    
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*
* ============================================================================
*/
package com.reactive.hzdfs.utils;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
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.AnnotationMetadata;
import org.springframework.core.type.ClassMetadata;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.core.type.filter.TypeFilter;
import org.springframework.util.StringUtils;

import com.reactive.hzdfs.cluster.IMapConfig;

public class EntityFinder {

    private static final Logger log = LoggerFactory.getLogger(EntityFinder.class);

    /**
     * 
     * @param provider
     * @param basePkg
     * @return
     * @throws ClassNotFoundException
     */
    private static Set<Class<?>> findComponents(ClassPathScanningCandidateComponentProvider provider,
            String basePkg) throws ClassNotFoundException {
        Set<BeanDefinition> beans = null;
        String pkg = "";
        try {
            pkg = StringUtils.hasText(basePkg) ? basePkg : EntityFinder.class.getPackage().getName();
            beans = provider.findCandidateComponents(pkg);
        } catch (Exception e) {
            throw new ClassNotFoundException("Unable to scan for classes under given base package",
                    new IllegalArgumentException("Package=> " + pkg, e));
        }

        Set<Class<?>> classes = new HashSet<>();
        if (beans != null && !beans.isEmpty()) {
            classes = new HashSet<>(beans.size());
            for (BeanDefinition bd : beans) {
                classes.add(Class.forName(bd.getBeanClassName()));
            }
        } else {
            log.warn(">> Did not find any classes under the given base package [" + basePkg + "]");
        }
        return classes;
    }

    /**
     * 
     * @param basePkg
     * @return
     * @throws ClassNotFoundException
     */
    public static Collection<Class<?>> findMapEntityClasses(String basePkg) throws ClassNotFoundException {
        ClassPathScanningCandidateComponentProvider provider = new ClassPathScanningCandidateComponentProvider(
                false);
        provider.addIncludeFilter(new TypeFilter() {

            @Override
            public boolean match(MetadataReader metadataReader, MetadataReaderFactory metadataReaderFactory)
                    throws IOException {
                AnnotationMetadata aMeta = metadataReader.getAnnotationMetadata();
                return aMeta.hasAnnotation(IMapConfig.class.getName());
            }
        });

        return findComponents(provider, basePkg);

    }

    /**
     * Find implementation classes for the given interface.
     * @param <T>
     * @param basePkg
     * @param baseInterface
     * @return
     * @throws ClassNotFoundException
     */
    @SuppressWarnings("unchecked")
    public static <T> List<Class<T>> findImplementationClasses(String basePkg, final Class<T> baseInterface)
            throws ClassNotFoundException {
        ClassPathScanningCandidateComponentProvider provider = new ClassPathScanningCandidateComponentProvider(
                false);
        provider.addIncludeFilter(new TypeFilter() {

            @Override
            public boolean match(MetadataReader metadataReader, MetadataReaderFactory metadataReaderFactory)
                    throws IOException {
                ClassMetadata aMeta = metadataReader.getClassMetadata();
                String[] intf = aMeta.getInterfaceNames();
                Arrays.sort(intf);
                return Arrays.binarySearch(intf, baseInterface.getName()) >= 0;
            }
        });

        Set<Class<?>> collection = findComponents(provider, basePkg);
        List<Class<T>> list = new ArrayList<>(collection.size());
        for (Class<?> c : collection) {
            list.add((Class<T>) c);
        }
        return list;

    }

}