Java URL Load findResourcesFromJar(Collection urls, URL url, String resource, ClassLoader cl)

Description

Find all resources from a given jar file and add them to the provided list.

License

Apache License

Parameter

Parameter	Description
urls	the non-<code>null</code> collection of resources where to add new found resources
url	the non-<code>null</code> url for the jar where to find resources
resource	the non-<code>null</code> resource being scanned that corresponds to given package
cl	the classloader to find the resources with

Declaration

private static void findResourcesFromJar(Collection<URL> urls, URL url, String resource, ClassLoader cl) 

Method Source Code

//package com.java2s;
/*/*  w  ww  .  j  a v a  2  s.co  m*/
 * Copyright (C) 2015-2015 The Helenus Driver Project Authors.
 *
 * 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.
 */

import java.io.IOException;
import java.net.JarURLConnection;
import java.net.URL;

import java.util.Collection;

import java.util.jar.JarEntry;
import java.util.jar.JarInputStream;

public class Main {
    /**
     * Find all resources from a given jar file and add them to the provided
     * list.
     *
     * @author paouelle
     *
     * @param urls the non-<code>null</code> collection of resources where to add new
     *        found resources
     * @param url the non-<code>null</code> url for the jar where to find resources
     * @param resource the non-<code>null</code> resource being scanned that
     *        corresponds to given package
     * @param cl the classloader to find the resources with
     */
    private static void findResourcesFromJar(Collection<URL> urls, URL url, String resource, ClassLoader cl) {
        try {
            final JarURLConnection conn = (JarURLConnection) url.openConnection();
            final URL jurl = conn.getJarFileURL();

            try (final JarInputStream jar = new JarInputStream(jurl.openStream());) {
                while (true) {
                    final JarEntry entry = jar.getNextJarEntry();

                    if (entry == null) {
                        break;
                    }
                    final String name = entry.getName();

                    if (name.startsWith(resource)) {
                        final URL u = cl.getResource(name);

                        if (u != null) {
                            urls.add(u);
                        }
                    }
                }
            }
        } catch (IOException e) {
            throw new IllegalArgumentException("unable to find resources in package", e);
        }
    }
}

Related

1. getBundle(String basename, Locale locale, ClassLoader cl, URL url)
2. getManifestAsString(URLClassLoader cl, String jarBaseName)
3. load(Iterable urls)
4. load(String fileOrURL)