tools/cli/src/main/java/org/apache/batchee/cli/command/JobOperatorCommand.java - incubator-batchee - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You 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 org.apache.batchee.cli.command;

 import org.apache.batchee.cli.classloader.ChildFirstURLClassLoader;
 import org.apache.batchee.cli.command.api.Option;
 import org.apache.batchee.cli.lifecycle.Lifecycle;
 import org.apache.batchee.cli.zip.Zips;
 import org.apache.batchee.container.exception.BatchContainerRuntimeException;
 import org.apache.batchee.jaxrs.client.BatchEEJAXRSClientFactory;
 import org.apache.batchee.jaxrs.client.ClientConfiguration;
 import org.apache.batchee.jaxrs.client.ClientSecurity;
 import org.apache.batchee.jaxrs.client.ClientSslConfiguration;
 import org.apache.commons.io.FileUtils;

 import javax.batch.operations.JobOperator;
 import javax.batch.runtime.BatchRuntime;
 import java.io.File;
 import java.io.FileFilter;
 import java.io.FilenameFilter;
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.Collection;
 import java.util.LinkedList;

 import static java.lang.Thread.currentThread;

 /**
  * base class handling:
  * - classloader enriched with libs folders (and subfolders)
  * - Lifecycle (allow to start/stop a container)
  *
  * Note: the classloader is created from libs command, it is handy to organize batches
  *       by folders to be able to run them contextual using this command.
 */
 public abstract class JobOperatorCommand implements Runnable {
     // Remote config

     @Option(name = "url", description = "when using JAXRS the batchee resource url")
     protected String baseUrl = null;

     @Option(name = "json", description = "when using JAXRS the json provider")
     private String jsonProvider = null;

     @Option(name = "user", description = "when using JAXRS the username")
     private String username = null;

     @Option(name = "password", description = "when using JAXRS the password")
     private String password = null;

     @Option(name = "auth", description = "when using JAXRS the authentication type (Basic)")
     private String type = "Basic";

     @Option(name = "hostnameVerifier", description = "when using JAXRS the hostname verifier")
     private String hostnameVerifier = null;

     @Option(name = "keystorePassword", description = "when using JAXRS the keystorePassword")
     private String keystorePassword = null;

     @Option(name = "keystoreType", description = "when using JAXRS the keystoreType (JKS)")
     private String keystoreType = "JKS";

     @Option(name = "keystorePath", description = "when using JAXRS the keystorePath")
     private String keystorePath = null;

     @Option(name = "sslContextType", description = "when using JAXRS the sslContextType (TLS)")
     private String sslContextType = "TLS";

     @Option(name = "keyManagerType", description = "when using JAXRS the keyManagerType (SunX509)")
     private String keyManagerType = "SunX509";

     @Option(name = "keyManagerPath", description = "when using JAXRS the keyManagerPath")
     private String keyManagerPath = null;

     @Option(name = "trustManagerAlgorithm", description = "when using JAXRS the trustManagerAlgorithm")
     private String trustManagerAlgorithm = null;

     @Option(name = "trustManagerProvider", description = "when using JAXRS the trustManagerProvider")
     private String trustManagerProvider = null;

     // local config

     @Option(name = "lifecycle", description = "the lifecycle class to use")
     private String lifecycle = null;

     @Option(name = "libs", description = "folder containing additional libraries, the folder is added too to the loader")
     private String libs = null;

     @Option(name = "archive", description = "a bar archive")
     private String archive = null;

     @Option(name = "work", description = "work directory (default to java.io.tmp/work)")
     private String work = System.getProperty("batchee.home", System.getProperty("java.io.tmpdir")) + "/work";

     @Option(name = "sharedLibs", description = "folder containing shared libraries, the folder is added too to the loader")
     private String sharedLibs = null;

     @Option(name = "addFolderToLoader", description = "force shared lib and libs folders to be added to the classloader")
     private boolean addFolderToLoader = false;

     protected JobOperator operator;

     protected JobOperator operator() {
         if (operator != null) {
             return operator;
         }

         if (baseUrl == null) {
             return operator = BatchRuntime.getJobOperator();
         }

         final ClientConfiguration configuration = new ClientConfiguration();
         configuration.setBaseUrl(baseUrl);
         configuration.setJsonProvider(jsonProvider);
         if (hostnameVerifier != null || keystorePath != null || keyManagerPath != null) {
             final ClientSslConfiguration ssl = new ClientSslConfiguration();
             configuration.setSsl(ssl);
             ssl.setHostnameVerifier(hostnameVerifier);
             ssl.setKeystorePassword(keystorePassword);
             ssl.setKeyManagerPath(keyManagerPath);
             ssl.setKeyManagerType(keyManagerType);
             ssl.setKeystorePath(keystorePath);
             ssl.setKeystoreType(keystoreType);
             ssl.setSslContextType(sslContextType);
             ssl.setTrustManagerAlgorithm(trustManagerAlgorithm);
             ssl.setTrustManagerProvider(trustManagerProvider);
         }
         final ClientSecurity security = new ClientSecurity();
         configuration.setSecurity(security);
         security.setUsername(username);
         security.setPassword(password);
         security.setType(type);

         return operator = BatchEEJAXRSClientFactory.newClient(configuration);
     }

     protected void info(final String text) {
         System.out.println(text);
     }

     protected abstract void doRun();

     @Override
     public final void run() {
         System.setProperty("org.apache.batchee.init.verbose.sysout", "true");

         final ClassLoader oldLoader = currentThread().getContextClassLoader();
         final ClassLoader loader;
         try {
             loader = createLoader(oldLoader);
         } catch (final MalformedURLException e) {
             throw new BatchContainerRuntimeException(e);
         }

         if (loader != oldLoader) {
             currentThread().setContextClassLoader(loader);
         }

         try {
             final Lifecycle<Object> lifecycleInstance;
             final Object state;

             if (lifecycle != null) {
                 lifecycleInstance = createLifecycle(loader);
                 state = lifecycleInstance.start();
             } else {
                 lifecycleInstance = null;
                 state = null;
             }

             try {
                 doRun();
             } finally {
                 if (lifecycleInstance != null) {
                     lifecycleInstance.stop(state);
                 }
             }
         } finally {
             currentThread().setContextClassLoader(oldLoader);
         }
     }

     private Lifecycle<Object> createLifecycle(final ClassLoader loader) {
         // some shortcuts are nicer to use from CLI
         if ("openejb".equalsIgnoreCase(lifecycle)) {
             lifecycle = "org.apache.batchee.cli.lifecycle.impl.OpenEJBLifecycle";
         } else if ("cdi".equalsIgnoreCase(lifecycle)) {
             lifecycle = "org.apache.batchee.cli.lifecycle.impl.CdiCtrlLifecycle";
         } else if ("spring".equalsIgnoreCase(lifecycle)) {
             lifecycle = "org.apache.batchee.cli.lifecycle.impl.SpringLifecycle";
         }

         try {
             return (Lifecycle<Object>) loader.loadClass(lifecycle).newInstance();
         } catch (final Exception e) {
             throw new BatchContainerRuntimeException(e);
         }
     }

     private ClassLoader createLoader(final ClassLoader parent) throws MalformedURLException {
         final Collection<URL> urls = new LinkedList<URL>();

         if (libs != null) {
             final File folder = new File(libs);
             if (folder.exists()) {
                 addFolder(folder, urls);
             }
         }

         // we add libs/*.jar and libs/xxx/*.jar to be able to sort libs but only one level to keep it simple
         File resources = null;
         File exploded = null;
         if (archive != null) {
             final File bar = new File(archive);
             if (bar.exists()) {
                 if (bar.isFile()) { // bar to unzip
                     exploded = new File(work, bar.getName());
                 } else if (bar.isDirectory()) { // already unpacked
                     exploded = bar;
                 } else {
                     throw new IllegalArgumentException("unsupported archive type for: '" + archive + "'");
                 }

                 final File timestamp = new File(exploded, "timestamp.txt");

                 long ts = Long.MIN_VALUE;
                 if (exploded.exists()) {
                     if (timestamp.exists()) {
                         try {
                             ts = Long.parseLong(FileUtils.readFileToString(timestamp).trim());
                         } catch (final IOException e) {
                             ts = Long.MIN_VALUE;
                         }
                     }
                 }

                 if (ts == Long.MIN_VALUE || ts < bar.lastModified()) {
                     explode(bar, exploded, timestamp, bar.lastModified());
                 }

                 if (archive.endsWith(".bar") || new File(exploded, "BATCH-INF").exists()) {
                     // bar archives are split accross 3 folders
                     addFolder(new File(exploded, "BATCH-INF/classes"), urls);
                     addFolderIfExist(new File(exploded, "BATCH-INF/lib"), urls);
                     resources = new File(exploded, "BATCH-INF");
                 } else if (archive.endsWith(".war") || new File(exploded, "WEB-INF").exists()) {
                     addFolderIfExist(new File(exploded, "WEB-INF/classes"), urls);
                     addLibs(new File(exploded, "WEB-INF/lib"), urls);
                 } else {
                     throw new IllegalArgumentException("unknown or unsupported archive type: " + archive);
                 }
             } else {
                 throw new IllegalArgumentException("'" + archive + "' doesn't exist");
             }
         }

         final ClassLoader sharedClassLoader = createSharedClassLoader(parent);
         if (libs == null && archive == null) {
             return sharedClassLoader;
         }

         final ChildFirstURLClassLoader classLoader = new ChildFirstURLClassLoader(urls.toArray(new URL[urls.size()]), sharedClassLoader);
         if (resources != null && resources.exists()) {
             classLoader.addResource(resources);
         }
         if (exploded != null) {
             classLoader.setApplicationFolder(exploded);
         }
         return classLoader;
     }

     private static void addFolderIfExist(final File file, final Collection<URL> urls) throws MalformedURLException {
         if (file.isDirectory()) {
             urls.add(file.toURI().toURL());
         }
     }

     private ClassLoader createSharedClassLoader(final ClassLoader parent) throws MalformedURLException {
         final ClassLoader usedParent;
         if (sharedLibs != null) { // add it later to let specific libs be taken before
             final Collection<URL> sharedUrls = new LinkedList<URL>();
             final File folder = new File(sharedLibs);
             addJars(folder, sharedUrls);
             if (ChildFirstURLClassLoader.class.isInstance(parent)) { // merge it
                 ChildFirstURLClassLoader.class.cast(parent).addUrls(sharedUrls);
                 usedParent = parent;
             } else {
                 usedParent = new ChildFirstURLClassLoader(sharedUrls.toArray(new URL[sharedUrls.size()]), parent);
             }
         } else {
             usedParent = parent;
         }
         return usedParent;
     }

     private void addJars(final File folder, final Collection<URL> urls) throws MalformedURLException {
         if (!folder.isDirectory()) {
             return;
         }

         addLibs(folder, urls);
         if (addFolderToLoader) {
             urls.add(folder.toURI().toURL());
         }
     }

     private void addFolder(File folder, Collection<URL> urls) throws MalformedURLException {
         if (!folder.exists()) {
             return;
         }

         addJars(folder, urls);

         final File[] subFolders = folder.listFiles(DirFilter.INSTANCE);
         if (subFolders != null) {
             for (final File f : subFolders) {
                 addJars(f, urls);
             }
         }
     }

     private static void addLibs(final File folder, final Collection<URL> urls) throws MalformedURLException {
         if (!folder.isDirectory()) {
             return;
         }

         final File[] additionals = folder.listFiles(JarFilter.INSTANCE);
         if (additionals != null) {
             for (final File toAdd : additionals) {
                 urls.add(toAdd.toURI().toURL());
             }
         }
     }

     private static void explode(final File source, final File target, final File timestampFile, final long time) {
         try {
             FileUtils.deleteDirectory(target);
             Zips.unzip(source, target);
             FileUtils.write(timestampFile, Long.toString(time));
         } catch (final IOException e) {
             // no-op
         }
     }

     private static class JarFilter implements FilenameFilter {
         public static final FilenameFilter INSTANCE = new JarFilter();

         private JarFilter() {
             // no-op
         }

         @Override
         public boolean accept(final File dir, final String name) {
             return name.endsWith(".jar") || name.endsWith(".zip");
         }
     }

     private static class DirFilter implements FileFilter {
         public static final FileFilter INSTANCE = new DirFilter();

         private DirFilter() {
             // no-op
         }

         @Override
         public boolean accept(final File dir) {
             return dir.isDirectory() && !dir.getName().startsWith(".");
         }
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You 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 org.apache.batchee.cli.command;

	import org.apache.batchee.cli.classloader.ChildFirstURLClassLoader;
	import org.apache.batchee.cli.command.api.Option;
	import org.apache.batchee.cli.lifecycle.Lifecycle;
	import org.apache.batchee.cli.zip.Zips;
	import org.apache.batchee.container.exception.BatchContainerRuntimeException;
	import org.apache.batchee.jaxrs.client.BatchEEJAXRSClientFactory;
	import org.apache.batchee.jaxrs.client.ClientConfiguration;
	import org.apache.batchee.jaxrs.client.ClientSecurity;
	import org.apache.batchee.jaxrs.client.ClientSslConfiguration;
	import org.apache.commons.io.FileUtils;

	import javax.batch.operations.JobOperator;
	import javax.batch.runtime.BatchRuntime;
	import java.io.File;
	import java.io.FileFilter;
	import java.io.FilenameFilter;
	import java.io.IOException;
	import java.net.MalformedURLException;
	import java.net.URL;
	import java.util.Collection;
	import java.util.LinkedList;

	import static java.lang.Thread.currentThread;

	/**
	* base class handling:
	* - classloader enriched with libs folders (and subfolders)
	* - Lifecycle (allow to start/stop a container)
	*
	* Note: the classloader is created from libs command, it is handy to organize batches
	* by folders to be able to run them contextual using this command.
	*/
	public abstract class JobOperatorCommand implements Runnable {
	// Remote config

	@Option(name = "url", description = "when using JAXRS the batchee resource url")
	protected String baseUrl = null;

	@Option(name = "json", description = "when using JAXRS the json provider")
	private String jsonProvider = null;

	@Option(name = "user", description = "when using JAXRS the username")
	private String username = null;

	@Option(name = "password", description = "when using JAXRS the password")
	private String password = null;

	@Option(name = "auth", description = "when using JAXRS the authentication type (Basic)")
	private String type = "Basic";

	@Option(name = "hostnameVerifier", description = "when using JAXRS the hostname verifier")
	private String hostnameVerifier = null;

	@Option(name = "keystorePassword", description = "when using JAXRS the keystorePassword")
	private String keystorePassword = null;

	@Option(name = "keystoreType", description = "when using JAXRS the keystoreType (JKS)")
	private String keystoreType = "JKS";

	@Option(name = "keystorePath", description = "when using JAXRS the keystorePath")
	private String keystorePath = null;

	@Option(name = "sslContextType", description = "when using JAXRS the sslContextType (TLS)")
	private String sslContextType = "TLS";

	@Option(name = "keyManagerType", description = "when using JAXRS the keyManagerType (SunX509)")
	private String keyManagerType = "SunX509";

	@Option(name = "keyManagerPath", description = "when using JAXRS the keyManagerPath")
	private String keyManagerPath = null;

	@Option(name = "trustManagerAlgorithm", description = "when using JAXRS the trustManagerAlgorithm")
	private String trustManagerAlgorithm = null;

	@Option(name = "trustManagerProvider", description = "when using JAXRS the trustManagerProvider")
	private String trustManagerProvider = null;

	// local config

	@Option(name = "lifecycle", description = "the lifecycle class to use")
	private String lifecycle = null;

	@Option(name = "libs", description = "folder containing additional libraries, the folder is added too to the loader")
	private String libs = null;

	@Option(name = "archive", description = "a bar archive")
	private String archive = null;

	@Option(name = "work", description = "work directory (default to java.io.tmp/work)")
	private String work = System.getProperty("batchee.home", System.getProperty("java.io.tmpdir")) + "/work";

	@Option(name = "sharedLibs", description = "folder containing shared libraries, the folder is added too to the loader")
	private String sharedLibs = null;

	@Option(name = "addFolderToLoader", description = "force shared lib and libs folders to be added to the classloader")
	private boolean addFolderToLoader = false;

	protected JobOperator operator;

	protected JobOperator operator() {
	if (operator != null) {
	return operator;
	}

	if (baseUrl == null) {
	return operator = BatchRuntime.getJobOperator();
	}

	final ClientConfiguration configuration = new ClientConfiguration();
	configuration.setBaseUrl(baseUrl);
	configuration.setJsonProvider(jsonProvider);
	if (hostnameVerifier != null \|\| keystorePath != null \|\| keyManagerPath != null) {
	final ClientSslConfiguration ssl = new ClientSslConfiguration();
	configuration.setSsl(ssl);
	ssl.setHostnameVerifier(hostnameVerifier);
	ssl.setKeystorePassword(keystorePassword);
	ssl.setKeyManagerPath(keyManagerPath);
	ssl.setKeyManagerType(keyManagerType);
	ssl.setKeystorePath(keystorePath);
	ssl.setKeystoreType(keystoreType);
	ssl.setSslContextType(sslContextType);
	ssl.setTrustManagerAlgorithm(trustManagerAlgorithm);
	ssl.setTrustManagerProvider(trustManagerProvider);
	}
	final ClientSecurity security = new ClientSecurity();
	configuration.setSecurity(security);
	security.setUsername(username);
	security.setPassword(password);
	security.setType(type);

	return operator = BatchEEJAXRSClientFactory.newClient(configuration);
	}

	protected void info(final String text) {
	System.out.println(text);
	}

	protected abstract void doRun();

	@Override
	public final void run() {
	System.setProperty("org.apache.batchee.init.verbose.sysout", "true");

	final ClassLoader oldLoader = currentThread().getContextClassLoader();
	final ClassLoader loader;
	try {
	loader = createLoader(oldLoader);
	} catch (final MalformedURLException e) {
	throw new BatchContainerRuntimeException(e);
	}

	if (loader != oldLoader) {
	currentThread().setContextClassLoader(loader);
	}

	try {
	final Lifecycle<Object> lifecycleInstance;
	final Object state;

	if (lifecycle != null) {
	lifecycleInstance = createLifecycle(loader);
	state = lifecycleInstance.start();
	} else {
	lifecycleInstance = null;
	state = null;
	}

	try {
	doRun();
	} finally {
	if (lifecycleInstance != null) {
	lifecycleInstance.stop(state);
	}
	}
	} finally {
	currentThread().setContextClassLoader(oldLoader);
	}
	}

	private Lifecycle<Object> createLifecycle(final ClassLoader loader) {
	// some shortcuts are nicer to use from CLI
	if ("openejb".equalsIgnoreCase(lifecycle)) {
	lifecycle = "org.apache.batchee.cli.lifecycle.impl.OpenEJBLifecycle";
	} else if ("cdi".equalsIgnoreCase(lifecycle)) {
	lifecycle = "org.apache.batchee.cli.lifecycle.impl.CdiCtrlLifecycle";
	} else if ("spring".equalsIgnoreCase(lifecycle)) {
	lifecycle = "org.apache.batchee.cli.lifecycle.impl.SpringLifecycle";
	}

	try {
	return (Lifecycle<Object>) loader.loadClass(lifecycle).newInstance();
	} catch (final Exception e) {
	throw new BatchContainerRuntimeException(e);
	}
	}

	private ClassLoader createLoader(final ClassLoader parent) throws MalformedURLException {
	final Collection<URL> urls = new LinkedList<URL>();

	if (libs != null) {
	final File folder = new File(libs);
	if (folder.exists()) {
	addFolder(folder, urls);
	}
	}

	// we add libs/.jar and libs/xxx/.jar to be able to sort libs but only one level to keep it simple
	File resources = null;
	File exploded = null;
	if (archive != null) {
	final File bar = new File(archive);
	if (bar.exists()) {
	if (bar.isFile()) { // bar to unzip
	exploded = new File(work, bar.getName());
	} else if (bar.isDirectory()) { // already unpacked
	exploded = bar;
	} else {
	throw new IllegalArgumentException("unsupported archive type for: '" + archive + "'");
	}

	final File timestamp = new File(exploded, "timestamp.txt");

	long ts = Long.MIN_VALUE;
	if (exploded.exists()) {
	if (timestamp.exists()) {
	try {
	ts = Long.parseLong(FileUtils.readFileToString(timestamp).trim());
	} catch (final IOException e) {
	ts = Long.MIN_VALUE;
	}
	}
	}

	if (ts == Long.MIN_VALUE \|\| ts < bar.lastModified()) {
	explode(bar, exploded, timestamp, bar.lastModified());
	}

	if (archive.endsWith(".bar") \|\| new File(exploded, "BATCH-INF").exists()) {
	// bar archives are split accross 3 folders
	addFolder(new File(exploded, "BATCH-INF/classes"), urls);
	addFolderIfExist(new File(exploded, "BATCH-INF/lib"), urls);
	resources = new File(exploded, "BATCH-INF");
	} else if (archive.endsWith(".war") \|\| new File(exploded, "WEB-INF").exists()) {
	addFolderIfExist(new File(exploded, "WEB-INF/classes"), urls);
	addLibs(new File(exploded, "WEB-INF/lib"), urls);
	} else {
	throw new IllegalArgumentException("unknown or unsupported archive type: " + archive);
	}
	} else {
	throw new IllegalArgumentException("'" + archive + "' doesn't exist");
	}
	}

	final ClassLoader sharedClassLoader = createSharedClassLoader(parent);
	if (libs == null && archive == null) {
	return sharedClassLoader;
	}

	final ChildFirstURLClassLoader classLoader = new ChildFirstURLClassLoader(urls.toArray(new URL[urls.size()]), sharedClassLoader);
	if (resources != null && resources.exists()) {
	classLoader.addResource(resources);
	}
	if (exploded != null) {
	classLoader.setApplicationFolder(exploded);
	}
	return classLoader;
	}

	private static void addFolderIfExist(final File file, final Collection<URL> urls) throws MalformedURLException {
	if (file.isDirectory()) {
	urls.add(file.toURI().toURL());
	}
	}

	private ClassLoader createSharedClassLoader(final ClassLoader parent) throws MalformedURLException {
	final ClassLoader usedParent;
	if (sharedLibs != null) { // add it later to let specific libs be taken before
	final Collection<URL> sharedUrls = new LinkedList<URL>();
	final File folder = new File(sharedLibs);
	addJars(folder, sharedUrls);
	if (ChildFirstURLClassLoader.class.isInstance(parent)) { // merge it
	ChildFirstURLClassLoader.class.cast(parent).addUrls(sharedUrls);
	usedParent = parent;
	} else {
	usedParent = new ChildFirstURLClassLoader(sharedUrls.toArray(new URL[sharedUrls.size()]), parent);
	}
	} else {
	usedParent = parent;
	}
	return usedParent;
	}

	private void addJars(final File folder, final Collection<URL> urls) throws MalformedURLException {
	if (!folder.isDirectory()) {
	return;
	}

	addLibs(folder, urls);
	if (addFolderToLoader) {
	urls.add(folder.toURI().toURL());
	}
	}

	private void addFolder(File folder, Collection<URL> urls) throws MalformedURLException {
	if (!folder.exists()) {
	return;
	}

	addJars(folder, urls);

	final File[] subFolders = folder.listFiles(DirFilter.INSTANCE);
	if (subFolders != null) {
	for (final File f : subFolders) {
	addJars(f, urls);
	}
	}
	}

	private static void addLibs(final File folder, final Collection<URL> urls) throws MalformedURLException {
	if (!folder.isDirectory()) {
	return;
	}

	final File[] additionals = folder.listFiles(JarFilter.INSTANCE);
	if (additionals != null) {
	for (final File toAdd : additionals) {
	urls.add(toAdd.toURI().toURL());
	}
	}
	}

	private static void explode(final File source, final File target, final File timestampFile, final long time) {
	try {
	FileUtils.deleteDirectory(target);
	Zips.unzip(source, target);
	FileUtils.write(timestampFile, Long.toString(time));
	} catch (final IOException e) {
	// no-op
	}
	}

	private static class JarFilter implements FilenameFilter {
	public static final FilenameFilter INSTANCE = new JarFilter();

	private JarFilter() {
	// no-op
	}

	@Override
	public boolean accept(final File dir, final String name) {
	return name.endsWith(".jar") \|\| name.endsWith(".zip");
	}
	}

	private static class DirFilter implements FileFilter {
	public static final FileFilter INSTANCE = new DirFilter();

	private DirFilter() {
	// no-op
	}

	@Override
	public boolean accept(final File dir) {
	return dir.isDirectory() && !dir.getName().startsWith(".");
	}
	}
	}