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The spring component framework is used to setup a plugin based, micro-kernel, standalone application (today, we will support webapp in later releases) which is based on SpringFramework. It can help you decouple your application into several components clearly with zero invasion and keep your application consistent between develop time and runtime.

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/**
 * @author XiongJie, Date: 13-11-27
 */
package net.happyonroad.component.classworld;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.Set;

/** the shared class loader for 3rd library  */
public class ClassLoaderRepresentation extends ClassLoader {

    private static SharedClassLoader sharedClassLoader = new SharedClassLoader();

    private final Set urls;

    public ClassLoaderRepresentation(Set urls) {
        sharedClassLoader.addURLs(urls);
        this.urls = urls;
    }

    @Override
    public Class loadClass(String name) throws ClassNotFoundException {
        Class theClass = sharedClassLoader.loadClass(name);
        URL hostUrl = sharedClassLoader.hostUrl(theClass);
        if(hostUrl == null) //it's loaded by parent actually, not by the shared instance
            return theClass;
        if(accessible(hostUrl))
            return theClass;
        else
            throw new ClassNotFoundException(name);
    }

    @Override
    public InputStream getResourceAsStream(String name) {
        URL url = sharedClassLoader.getResource(name);
        try {
            return url != null ? url.openStream() : null;
        } catch (IOException e) {
            return null;
        }
    }

    @Override
    public URL getResource(String name) {
        URL url = sharedClassLoader.getResource(name);
        if(accessible(url))
            return url;
        else
            return null;
    }

    //judge the url is accessible from this class representation or not
    private boolean accessible(URL resourceUrl) {
        if(resourceUrl == null)
            return false;
        for (URL url : urls) {
            if( resourceUrl.toString().contains(url.toString()))
                return true;
        }
        return false;
    }

    @Override
    public Enumeration getResources(String name) throws IOException {
        Enumeration resources = sharedClassLoader.getResources(name);
        Set urls = new HashSet();
        while (resources.hasMoreElements()) {
            URL url = resources.nextElement();
            if(accessible(url)) urls.add(url);
        }
        return Collections.enumeration(urls);
    }
}