IteratorFactory.java

package net.csdn.modules.scan.component;

import java.io.IOException;
import java.net.URL;
import java.util.concurrent.ConcurrentHashMap;

/**
 * @author <a href="mailto:bill@burkecentral.com">Bill Burke</a>
 * @version $Revision: 1 $
 */
public class IteratorFactory {
    private static final ConcurrentHashMap<String, DirectoryIteratorFactory> registry = new ConcurrentHashMap<String, DirectoryIteratorFactory>();

    static {
        registry.put("file", new FileProtocolIteratorFactory());
    }


    public static StreamIterator create(URL url, Filter filter) throws IOException {
        String urlString = url.toString();
        if (urlString.endsWith("!/")) {
            urlString = urlString.substring(4);
            urlString = urlString.substring(0, urlString.length() - 2);
            url = new URL(urlString);
        }


        if (!urlString.endsWith("/")) {
            return new JarIterator(url.openStream(), filter);
        } else {
            DirectoryIteratorFactory factory = registry.get(url.getProtocol());
            if (factory == null) throw new IOException("Unable to scan directory of protocol: " + url.getProtocol());
            return factory.create(url, filter);
        }
    }
}