X-Git-Url: https://git.argeo.org/?a=blobdiff_plain;ds=inline;f=org.argeo.cms%2Fsrc%2Forg%2Fargeo%2Fcms%2Finternal%2Fkernel%2FKernel.java;h=1f562b817cfeff0f1bcafeb3bfb222d96c537750;hb=6ed2ce8f490e2fc020e67f530f8c08e250b7b6dd;hp=4b893f13d0b6e195be13c8354b8ab2dc756d8cb0;hpb=559786a622e24c7d213960a7873e105db82a03ab;p=lgpl%2Fargeo-commons.git
diff --git a/org.argeo.cms/src/org/argeo/cms/internal/kernel/Kernel.java b/org.argeo.cms/src/org/argeo/cms/internal/kernel/Kernel.java
index 4b893f13d..1f562b817 100644
--- a/org.argeo.cms/src/org/argeo/cms/internal/kernel/Kernel.java
+++ b/org.argeo.cms/src/org/argeo/cms/internal/kernel/Kernel.java
@@ -1,20 +1,69 @@
package org.argeo.cms.internal.kernel;
+import static bitronix.tm.TransactionManagerServices.getTransactionManager;
+import static bitronix.tm.TransactionManagerServices.getTransactionSynchronizationRegistry;
+import static java.util.Locale.ENGLISH;
+import static org.argeo.cms.internal.kernel.KernelUtils.getFrameworkProp;
+import static org.argeo.cms.internal.kernel.KernelUtils.getOsgiInstanceDir;
+import static org.argeo.jcr.ArgeoJcrConstants.ALIAS_NODE;
+import static org.argeo.jcr.ArgeoJcrConstants.JCR_REPOSITORY_ALIAS;
+import static org.argeo.util.LocaleChoice.asLocaleList;
+import static org.osgi.framework.Constants.FRAMEWORK_UUID;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileFilter;
+import java.io.IOException;
+import java.lang.management.ManagementFactory;
+import java.security.PrivilegedAction;
+import java.util.HashMap;
import java.util.Hashtable;
+import java.util.List;
+import java.util.Locale;
+import java.util.Map;
+import javax.jcr.ImportUUIDBehavior;
+import javax.jcr.Repository;
import javax.jcr.RepositoryFactory;
+import javax.jcr.Session;
+import javax.jcr.SimpleCredentials;
+import javax.security.auth.Subject;
+import javax.transaction.TransactionManager;
+import javax.transaction.TransactionSynchronizationRegistry;
+import javax.transaction.UserTransaction;
+import org.apache.commons.io.FileUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
+import org.apache.jackrabbit.api.JackrabbitRepository;
+import org.apache.jackrabbit.util.TransientFileFactory;
import org.argeo.ArgeoException;
+import org.argeo.ArgeoLogger;
+import org.argeo.cms.CmsException;
+import org.argeo.cms.maintenance.MaintenanceUi;
import org.argeo.jackrabbit.OsgiJackrabbitRepositoryFactory;
-import org.argeo.security.core.InternalAuthentication;
+import org.argeo.jcr.ArgeoJcrConstants;
+import org.argeo.jcr.ArgeoJcrUtils;
+import org.eclipse.equinox.http.jetty.JettyConfigurator;
+import org.eclipse.equinox.http.jetty.JettyConstants;
+import org.eclipse.equinox.http.servlet.ExtendedHttpService;
import org.eclipse.rap.rwt.application.ApplicationConfiguration;
-import org.eclipse.rap.rwt.osgi.ApplicationLauncher;
-import org.eclipse.rap.ui.internal.servlet.WorkbenchApplicationConfiguration;
import org.osgi.framework.BundleContext;
+import org.osgi.framework.ServiceEvent;
+import org.osgi.framework.ServiceListener;
+import org.osgi.framework.ServiceReference;
import org.osgi.framework.ServiceRegistration;
-import org.springframework.security.core.context.SecurityContextHolder;
+import org.osgi.framework.startlevel.BundleStartLevel;
+import org.osgi.service.cm.Configuration;
+import org.osgi.service.cm.ConfigurationAdmin;
+import org.osgi.service.log.LogReaderService;
+import org.osgi.service.useradmin.UserAdmin;
+import org.osgi.util.tracker.ServiceTracker;
+
+import bitronix.tm.BitronixTransactionManager;
+import bitronix.tm.BitronixTransactionSynchronizationRegistry;
+import bitronix.tm.TransactionManagerServices;
/**
* Argeo CMS Kernel. Responsible for :
@@ -27,87 +76,423 @@ import org.springframework.security.core.context.SecurityContextHolder;
*
OS access
*
*/
-@SuppressWarnings("restriction")
-final class Kernel {
- private final static Log log = LogFactory.getLog(Kernel.class);
- private static final String PROP_WORKBENCH_AUTOSTART = "org.eclipse.rap.workbenchAutostart";
+final class Kernel implements KernelHeader, KernelConstants, ServiceListener {
+ /*
+ * SERVICE REFERENCES
+ */
+ private ServiceReference configurationAdmin;
+ /*
+ * REGISTERED SERVICES
+ */
+ private ServiceRegistration loggerReg;
+ private ServiceRegistration tmReg;
+ private ServiceRegistration utReg;
+ private ServiceRegistration tsrReg;
+ private ServiceRegistration extends Repository> repositoryReg;
+ private ServiceRegistration repositoryFactoryReg;
+ private ServiceRegistration userAdminReg;
- private final BundleContext bundleContext;
+ /*
+ * SERVICES IMPLEMENTATIONS
+ */
+ private NodeLogger logger;
+ private BitronixTransactionManager transactionManager;
+ private BitronixTransactionSynchronizationRegistry transactionSynchronizationRegistry;
+ private OsgiJackrabbitRepositoryFactory repositoryFactory;
+ NodeRepository repository;
+ private NodeUserAdmin userAdmin;
- private JackrabbitNode node;
- private RepositoryFactory repositoryFactory;
- private NodeSecurity nodeSecurity;
+ // Members
+ private final static Log log = LogFactory.getLog(Kernel.class);
+ ThreadGroup threadGroup = new ThreadGroup(Kernel.class.getSimpleName());
+ private final BundleContext bc = Activator.getBundleContext();
+ private final NodeSecurity nodeSecurity;
+ private DataHttp dataHttp;
private NodeHttp nodeHttp;
+ private KernelThread kernelThread;
+
+ private Locale defaultLocale = null;
+ private List locales = null;
- private ServiceRegistration workbenchReg;
+ public Kernel() {
+ // KernelUtils.logFrameworkProperties(log);
+ nodeSecurity = new NodeSecurity();
+ }
- Kernel(BundleContext bundleContext) {
- this.bundleContext = bundleContext;
+ final void init() {
+ Subject.doAs(nodeSecurity.getKernelSubject(),
+ new PrivilegedAction() {
+ @Override
+ public Void run() {
+ doInit();
+ return null;
+ }
+ });
}
- void init() {
+ private void doInit() {
long begin = System.currentTimeMillis();
- InternalAuthentication initAuth = new InternalAuthentication(
- KernelConstants.DEFAULT_SECURITY_KEY);
- SecurityContextHolder.getContext().setAuthentication(initAuth);
+ // Use CMS bundle classloader
+ ClassLoader currentContextCl = Thread.currentThread()
+ .getContextClassLoader();
+ Thread.currentThread().setContextClassLoader(
+ Kernel.class.getClassLoader());
+ try {
+ if (nodeSecurity.isFirstInit())
+ firstInit();
+
+ defaultLocale = new Locale(getFrameworkProp(I18N_DEFAULT_LOCALE,
+ ENGLISH.getLanguage()));
+ locales = asLocaleList(getFrameworkProp(I18N_LOCALES));
+
+ ServiceTracker logReaderService = new ServiceTracker(
+ bc, LogReaderService.class, null);
+ logReaderService.open();
+ logger = new NodeLogger(logReaderService.getService());
+ logReaderService.close();
+
+ if (isMaintenance())
+ maintenanceInit();
+ else
+ normalInit();
+ } catch (Exception e) {
+ log.error("Cannot initialize Argeo CMS", e);
+ throw new ArgeoException("Cannot initialize", e);
+ } finally {
+ Thread.currentThread().setContextClassLoader(currentContextCl);
+ }
+
+ long jvmUptime = ManagementFactory.getRuntimeMXBean().getUptime();
+ log.info("## ARGEO CMS UP in " + (jvmUptime / 1000) + "."
+ + (jvmUptime % 1000) + "s ##");
+ long initDuration = System.currentTimeMillis() - begin;
+ if (log.isTraceEnabled())
+ log.trace("Kernel initialization took " + initDuration + "ms");
+ directorsCut(initDuration);
+ }
+
+ private void normalInit() {
+ ConfigurationAdmin conf = findConfigurationAdmin();
+ // Initialise services
+ initTransactionManager();
+ if (repository == null)
+ repository = new NodeRepository();
+ if (repositoryFactory == null)
+ repositoryFactory = new OsgiJackrabbitRepositoryFactory();
+ userAdmin = new NodeUserAdmin(transactionManager, repository);
+
+ // HTTP
+ initWebServer(conf);
+ ServiceReference sr = bc
+ .getServiceReference(ExtendedHttpService.class);
+ if (sr != null)
+ addHttpService(sr);
+
+ // ADMIN UIs
+ UserUi userUi = new UserUi();
+ Hashtable props = new Hashtable();
+ props.put("contextName", "user");
+ bc.registerService(ApplicationConfiguration.class, userUi, props);
+
+ // Kernel thread
+ kernelThread = new KernelThread(this);
+ kernelThread.setContextClassLoader(Kernel.class.getClassLoader());
+ kernelThread.start();
+ // Publish services to OSGi
+ publish();
+ }
+
+ private boolean isMaintenance() {
+ String startLevel = KernelUtils.getFrameworkProp("osgi.startLevel");
+ if (startLevel == null)
+ return false;
+ int bundleStartLevel = bc.getBundle().adapt(BundleStartLevel.class)
+ .getStartLevel();
+ // int frameworkStartLevel =
+ // bc.getBundle(0).adapt(BundleStartLevel.class)
+ // .getStartLevel();
+ int frameworkStartLevel = Integer.parseInt(startLevel);
+ // int frameworkStartLevel = bc.getBundle(0)
+ // .adapt(FrameworkStartLevel.class).getStartLevel();
+ return bundleStartLevel == frameworkStartLevel;
+ }
+
+ private void maintenanceInit() {
+ log.info("## MAINTENANCE ##");
+ bc.addServiceListener(Kernel.this);
+ initWebServer(null);
+ MaintenanceUi maintenanceUi = new MaintenanceUi();
+ Hashtable props = new Hashtable();
+ props.put("contextName", "maintenance");
+ bc.registerService(ApplicationConfiguration.class, maintenanceUi, props);
+ }
+
+ private void firstInit() {
+ log.info("## FIRST INIT ##");
+ String nodeInit = getFrameworkProp(NODE_INIT);
+ if (nodeInit == null)
+ nodeInit = "../../init";
+ if (nodeInit.startsWith("http")) {
+ remoteFirstInit(nodeInit);
+ return;
+ }
+ File initDir;
+ if (nodeInit.startsWith("."))
+ initDir = KernelUtils.getExecutionDir(nodeInit);
+ else
+ initDir = new File(nodeInit);
+ // TODO also uncompress archives
+ if (initDir.exists())
+ try {
+ FileUtils.copyDirectory(initDir, getOsgiInstanceDir(),
+ new FileFilter() {
+
+ @Override
+ public boolean accept(File pathname) {
+ if (pathname.getName().equals(".svn")
+ || pathname.getName().equals(".git"))
+ return false;
+ return true;
+ }
+ });
+ log.info("CMS initialized from " + initDir.getCanonicalPath());
+ } catch (IOException e) {
+ throw new CmsException("Cannot initialize from " + initDir, e);
+ }
+ }
+
+ private void remoteFirstInit(String uri) {
try {
- node = new JackrabbitNode(bundleContext);
+ repository = new NodeRepository();
repositoryFactory = new OsgiJackrabbitRepositoryFactory();
- nodeSecurity = new NodeSecurity(bundleContext, node);
- nodeHttp = new NodeHttp(bundleContext, node, nodeSecurity);
-
- // Publish services to OSGi
- nodeSecurity.publish();
- node.publish();
- bundleContext.registerService(RepositoryFactory.class,
- repositoryFactory, null);
- nodeHttp.publish();
-
- if ("false".equals(bundleContext
- .getProperty(PROP_WORKBENCH_AUTOSTART))) {
- WorkbenchApplicationConfiguration wac = new WorkbenchApplicationConfiguration();
- registerWorkbench(wac);
+ Repository remoteRepository = ArgeoJcrUtils.getRepositoryByUri(
+ repositoryFactory, uri);
+ Session remoteSession = remoteRepository
+ .login(new SimpleCredentials("root", "demo".toCharArray()),
+ "main");
+ Session localSession = this.repository.login();
+ // FIXME register node type
+ // if (false)
+ // CndImporter.registerNodeTypes(null, localSession);
+ ByteArrayOutputStream out = new ByteArrayOutputStream();
+ remoteSession.exportSystemView("/", out, true, false);
+ ByteArrayInputStream in = new ByteArrayInputStream(
+ out.toByteArray());
+ localSession.importXML("/", in,
+ ImportUUIDBehavior.IMPORT_UUID_COLLISION_THROW);
+ // JcrUtils.copy(remoteSession.getRootNode(),
+ // localSession.getRootNode());
+ } catch (Exception e) {
+ throw new CmsException("Cannot first init from " + uri, e);
+ }
+ }
+
+ /** Can be null */
+ private ConfigurationAdmin findConfigurationAdmin() {
+ configurationAdmin = bc.getServiceReference(ConfigurationAdmin.class);
+ if (configurationAdmin == null) {
+ return null;
+ }
+ return bc.getService(configurationAdmin);
+ }
+
+ private void initTransactionManager() {
+ bitronix.tm.Configuration tmConf = TransactionManagerServices
+ .getConfiguration();
+ tmConf.setServerId(getFrameworkProp(FRAMEWORK_UUID));
+
+ // File tmBaseDir = new File(getFrameworkProp(TRANSACTIONS_HOME,
+ // getOsgiInstancePath(DIR_TRANSACTIONS)));
+ File tmBaseDir = bc.getDataFile(DIR_TRANSACTIONS);
+ File tmDir1 = new File(tmBaseDir, "btm1");
+ tmDir1.mkdirs();
+ tmConf.setLogPart1Filename(new File(tmDir1, tmDir1.getName() + ".tlog")
+ .getAbsolutePath());
+ File tmDir2 = new File(tmBaseDir, "btm2");
+ tmDir2.mkdirs();
+ tmConf.setLogPart2Filename(new File(tmDir2, tmDir2.getName() + ".tlog")
+ .getAbsolutePath());
+ transactionManager = getTransactionManager();
+ transactionSynchronizationRegistry = getTransactionSynchronizationRegistry();
+ }
+
+ private void initWebServer(ConfigurationAdmin conf) {
+ String httpPort = getFrameworkProp("org.osgi.service.http.port");
+ String httpsPort = getFrameworkProp("org.osgi.service.http.port.secure");
+ try {
+ if (httpPort != null || httpsPort != null) {
+ Hashtable jettyProps = new Hashtable();
+ if (httpPort != null) {
+ jettyProps.put(JettyConstants.HTTP_PORT, httpPort);
+ jettyProps.put(JettyConstants.HTTP_ENABLED, true);
+ }
+ if (httpsPort != null) {
+ jettyProps.put(JettyConstants.HTTPS_PORT, httpsPort);
+ jettyProps.put(JettyConstants.HTTPS_ENABLED, true);
+ jettyProps.put(JettyConstants.SSL_KEYSTORETYPE, "PKCS12");
+ jettyProps.put(JettyConstants.SSL_KEYSTORE, nodeSecurity
+ .getHttpServerKeyStore().getCanonicalPath());
+ jettyProps.put(JettyConstants.SSL_PASSWORD, "changeit");
+ jettyProps.put(JettyConstants.SSL_WANTCLIENTAUTH, true);
+ }
+ if (conf != null) {
+ // TODO make filter more generic
+ String filter = "(" + JettyConstants.HTTP_PORT + "="
+ + httpPort + ")";
+ if (conf.listConfigurations(filter) != null)
+ return;
+ Configuration jettyConf = conf.createFactoryConfiguration(
+ JETTY_FACTORY_PID, null);
+ jettyConf.update(jettyProps);
+ } else {
+ JettyConfigurator.startServer("default", jettyProps);
+ }
}
} catch (Exception e) {
- log.error("Cannot initialize Argeo CMS", e);
- throw new ArgeoException("Cannot initialize", e);
+ throw new CmsException("Cannot initialize web server on "
+ + httpPortsMsg(httpPort, httpsPort), e);
}
+ }
- long duration = System.currentTimeMillis() - begin;
- log.info("## ARGEO CMS UP in " + (duration / 1000) + "."
- + (duration % 1000) + "s ##");
- directorsCut();
+ @SuppressWarnings("unchecked")
+ private void publish() {
+ // Listen to service publication (also ours)
+ bc.addServiceListener(Kernel.this);
+
+ // Logging
+ loggerReg = bc.registerService(ArgeoLogger.class, logger, null);
+ // Transaction
+ tmReg = bc.registerService(TransactionManager.class,
+ transactionManager, null);
+ utReg = bc.registerService(UserTransaction.class, transactionManager,
+ null);
+ tsrReg = bc.registerService(TransactionSynchronizationRegistry.class,
+ transactionSynchronizationRegistry, null);
+ // User admin
+ userAdminReg = bc.registerService(UserAdmin.class, userAdmin,
+ userAdmin.currentState());
+ // JCR
+ Hashtable regProps = new Hashtable();
+ regProps.put(JCR_REPOSITORY_ALIAS, ALIAS_NODE);
+ repositoryReg = (ServiceRegistration extends Repository>) bc
+ .registerService(new String[] { Repository.class.getName(),
+ JackrabbitRepository.class.getName() }, repository,
+ regProps);
+ repositoryFactoryReg = bc.registerService(RepositoryFactory.class,
+ repositoryFactory, null);
}
void destroy() {
long begin = System.currentTimeMillis();
+ unpublish();
- // OSGi
- workbenchReg.unregister();
+ kernelThread.destroyAndJoin();
- nodeHttp = null;
- nodeSecurity.destroy();
- node.destroy();
+ if (dataHttp != null)
+ dataHttp.destroy();
+ if (nodeHttp != null)
+ nodeHttp.destroy();
+ if (userAdmin != null)
+ userAdmin.destroy();
+ if (repository != null)
+ repository.destroy();
+ if (transactionManager != null)
+ transactionManager.shutdown();
+
+ bc.removeServiceListener(this);
+ // Clean hanging threads from Jackrabbit
+ TransientFileFactory.shutdown();
+
+ // Clean hanging Gogo shell thread
+ new GogoShellKiller().start();
+
+ nodeSecurity.destroy();
long duration = System.currentTimeMillis() - begin;
log.info("## ARGEO CMS DOWN in " + (duration / 1000) + "."
+ (duration % 1000) + "s ##");
}
- private void registerWorkbench(final WorkbenchApplicationConfiguration wac) {
- new Thread("Worbench Launcher") {
- public void run() {
- Hashtable props = new Hashtable();
- props.put(ApplicationLauncher.PROPERTY_CONTEXT_NAME, "ui");
- workbenchReg = bundleContext.registerService(
- ApplicationConfiguration.class, wac, props);
+ private void unpublish() {
+ userAdminReg.unregister();
+ repositoryFactoryReg.unregister();
+ repositoryReg.unregister();
+ tmReg.unregister();
+ utReg.unregister();
+ tsrReg.unregister();
+ loggerReg.unregister();
+ }
+
+ @Override
+ public void serviceChanged(ServiceEvent event) {
+ ServiceReference> sr = event.getServiceReference();
+ Object service = bc.getService(sr);
+ if (service instanceof Repository) {
+ Object jcrRepoAlias = sr
+ .getProperty(ArgeoJcrConstants.JCR_REPOSITORY_ALIAS);
+ if (jcrRepoAlias != null) {// JCR repository
+ String alias = jcrRepoAlias.toString();
+ Repository repository = (Repository) bc.getService(sr);
+ Map props = new HashMap();
+ for (String key : sr.getPropertyKeys())
+ props.put(key, sr.getProperty(key));
+ if (ServiceEvent.REGISTERED == event.getType()) {
+ try {
+ repositoryFactory.register(repository, props);
+ dataHttp.registerRepositoryServlets(alias, repository);
+ } catch (Exception e) {
+ throw new CmsException(
+ "Could not publish JCR repository " + alias, e);
+ }
+ } else if (ServiceEvent.UNREGISTERING == event.getType()) {
+ repositoryFactory.unregister(repository, props);
+ dataHttp.unregisterRepositoryServlets(alias);
+ }
}
- }.start();
+ } else if (service instanceof ExtendedHttpService) {
+ if (ServiceEvent.REGISTERED == event.getType()) {
+ addHttpService(sr);
+ } else if (ServiceEvent.UNREGISTERING == event.getType()) {
+ dataHttp.destroy();
+ dataHttp = null;
+ }
+ }
+ }
+
+ private void addHttpService(ServiceReference> sr) {
+ // for (String key : sr.getPropertyKeys())
+ // log.debug(key + "=" + sr.getProperty(key));
+ ExtendedHttpService httpService = (ExtendedHttpService) bc
+ .getService(sr);
+ // TODO find constants
+ Object httpPort = sr.getProperty("http.port");
+ Object httpsPort = sr.getProperty("https.port");
+ dataHttp = new DataHttp(httpService, repository);
+ nodeHttp = new NodeHttp(httpService);
+ if (log.isDebugEnabled())
+ log.debug(httpPortsMsg(httpPort, httpsPort));
}
- private void directorsCut() {
- final long ms = 128l + (long) (Math.random() * 128d);
+ private String httpPortsMsg(Object httpPort, Object httpsPort) {
+ return "HTTP " + httpPort
+ + (httpsPort != null ? " - HTTPS " + httpsPort : "");
+ }
+
+ @Override
+ public Locale getDefaultLocale() {
+ return defaultLocale;
+ }
+
+ /** Can be null. */
+ @Override
+ public List getLocales() {
+ return locales;
+ }
+
+ final private static void directorsCut(long initDuration) {
+ // final long ms = 128l + (long) (Math.random() * 128d);
+ long ms = initDuration / 100;
log.info("Spend " + ms + "ms"
+ " reflecting on the progress brought to mankind"
+ " by Free Software...");
@@ -122,7 +507,65 @@ final class Kernel {
double sleepAccuracy = ((double) durationNano) / (ms * M);
if (log.isDebugEnabled())
log.debug("Sleep accuracy: "
- + String.format("%.2f", sleepAccuracy * 100) + " %");
+ + String.format("%.2f", 100 - (sleepAccuracy * 100 - 100))
+ + " %");
+ }
+
+ /** Workaround for blocking Gogo shell by system shutdown. */
+ private class GogoShellKiller extends Thread {
+
+ public GogoShellKiller() {
+ super("Gogo shell killer");
+ setDaemon(true);
+ }
+
+ @Override
+ public void run() {
+ ThreadGroup rootTg = getRootThreadGroup(null);
+ Thread gogoShellThread = findGogoShellThread(rootTg);
+ if (gogoShellThread == null)
+ return;
+ while (getNonDaemonCount(rootTg) > 2) {
+ try {
+ Thread.sleep(100);
+ } catch (InterruptedException e) {
+ // silent
+ }
+ }
+ gogoShellThread = findGogoShellThread(rootTg);
+ if (gogoShellThread == null)
+ return;
+ System.exit(0);
+ }
+ }
+
+ private static ThreadGroup getRootThreadGroup(ThreadGroup tg) {
+ if (tg == null)
+ tg = Thread.currentThread().getThreadGroup();
+ if (tg.getParent() == null)
+ return tg;
+ else
+ return getRootThreadGroup(tg.getParent());
+ }
+
+ private static int getNonDaemonCount(ThreadGroup rootThreadGroup) {
+ Thread[] threads = new Thread[rootThreadGroup.activeCount()];
+ rootThreadGroup.enumerate(threads);
+ int nonDameonCount = 0;
+ for (Thread t : threads)
+ if (!t.isDaemon())
+ nonDameonCount++;
+ return nonDameonCount;
+ }
+
+ private static Thread findGogoShellThread(ThreadGroup rootThreadGroup) {
+ Thread[] threads = new Thread[rootThreadGroup.activeCount()];
+ rootThreadGroup.enumerate(threads, true);
+ for (Thread thread : threads) {
+ if (thread.getName().equals("Gogo shell"))
+ return thread;
+ }
+ return null;
}
-}
+}
\ No newline at end of file