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/*
* 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.ode.store;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.ode.bpel.compiler.api.CompilationException;
import org.apache.ode.bpel.dd.DeployDocument;
import org.apache.ode.bpel.dd.TDeployment;
import org.apache.ode.bpel.iapi.ContextException;
import org.apache.ode.bpel.iapi.ProcessConf;
import org.apache.ode.bpel.iapi.ProcessState;
import org.apache.ode.bpel.iapi.ProcessStore;
import org.apache.ode.bpel.iapi.ProcessStoreEvent;
import org.apache.ode.bpel.iapi.ProcessStoreListener;
import org.apache.ode.bpel.iapi.EndpointReferenceContext;
import org.apache.ode.store.DeploymentUnitDir.CBPInfo;
import org.apache.ode.utils.DOMUtils;
import org.apache.ode.utils.GUID;
import org.apache.ode.utils.msg.MessageBundle;
import org.apache.ode.il.config.OdeConfigProperties;
import org.hsqldb.jdbc.jdbcDataSource;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import javax.sql.DataSource;
import javax.xml.namespace.QName;
import java.io.File;
import java.io.IOException;
import java.sql.SQLException;
import java.util.*;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.locks.ReadWriteLock;
import java.util.concurrent.locks.ReentrantReadWriteLock;
/**
* <p>
* JDBC-based implementation of a process store. Also provides an "in-memory" store by way of HSQL database.
* </p>
*
* <p>
* The philsophy here is to keep things simple. Process store operations are relatively infrequent. Performance of the public
* methods is not a concern. However, note that the {@link org.apache.ode.bpel.iapi.ProcessConf} objects returned by the class are
* going to be used from within the engine runtime, and hence their performance needs to be very good. Similarly, these objects
* should be immutable so as not to confuse the engine.
*
* Note the way that the database is used in this class, it is more akin to a recovery log, this is intentional: we want to start
* up, load stuff from the database and then pretty much forget about it when it comes to reads.
*
* @author Maciej Szefler <mszefler at gmail dot com>
* @author mriou <mriou at apache dot org>
*/
public class ProcessStoreImpl implements ProcessStore {
private static final Log __log = LogFactory.getLog(ProcessStoreImpl.class);
private static final Messages __msgs = MessageBundle.getMessages(Messages.class);
private final CopyOnWriteArrayList<ProcessStoreListener> _listeners = new CopyOnWriteArrayList<ProcessStoreListener>();
private Map<QName, ProcessConfImpl> _processes = new HashMap<QName, ProcessConfImpl>();
private Map<String, DeploymentUnitDir> _deploymentUnits = new HashMap<String, DeploymentUnitDir>();
/** Guards access to the _processes and _deploymentUnits */
private final ReadWriteLock _rw = new ReentrantReadWriteLock();
private ConfStoreConnectionFactory _cf;
private EndpointReferenceContext eprContext;
protected File _deployDir;
protected File _configDir;
/**
* Executor used to process DB transactions. Allows us to isolate the TX context, and to ensure that only one TX gets executed a
* time. We don't really care to parallelize these operations because: i) HSQL does not isolate transactions and we don't want
* to get confused ii) we're already serializing all the operations with a read/write lock. iii) we don't care about
* performance, these are infrequent operations.
*/
private ExecutorService _executor = Executors.newSingleThreadExecutor(new SimpleThreadFactory());
/**
* In-memory DataSource, or <code>null</code> if we are using a real DS. We need this to shutdown the DB.
*/
private DataSource _inMemDs;
public ProcessStoreImpl() {
this(null, null, "", new OdeConfigProperties(new Properties(), ""), true);
}
public ProcessStoreImpl(EndpointReferenceContext eprContext, DataSource ds, String persistenceType, OdeConfigProperties props, boolean createDatamodel) {
this.eprContext = eprContext;
if (ds != null) {
// ugly hack
if (persistenceType.toLowerCase().indexOf("hib") != -1)
_cf = new org.apache.ode.store.hib.DbConfStoreConnectionFactory(ds, props.getProperties(), createDatamodel);
else
_cf = new org.apache.ode.store.jpa.DbConfStoreConnectionFactory(ds, createDatamodel);
} else {
// If the datasource is not provided, then we create a HSQL-based in-memory
// database. Makes testing a bit simpler.
DataSource hsqlds = createInternalDS(new GUID().toString());
if ("hibernate".equalsIgnoreCase(persistenceType))
_cf = new org.apache.ode.store.hib.DbConfStoreConnectionFactory(hsqlds, props.getProperties(), createDatamodel);
else
_cf = new org.apache.ode.store.jpa.DbConfStoreConnectionFactory(hsqlds, createDatamodel);
_inMemDs = hsqlds;
}
}
/**
* Constructor that hardwires OpenJPA on a new in-memory database. Suitable for tests.
*/
public ProcessStoreImpl(EndpointReferenceContext eprContext, DataSource inMemDs) {
this.eprContext = eprContext;
DataSource hsqlds = createInternalDS(new GUID().toString());
//when in memory we always create the model as we are starting from scratch
_cf = new org.apache.ode.store.jpa.DbConfStoreConnectionFactory(hsqlds, true);
_inMemDs = hsqlds;
}
public void shutdown() {
if (_inMemDs != null) {
shutdownInternalDB(_inMemDs);
_inMemDs = null;
}
}
@Override
protected void finalize() throws Throwable {
// force a shutdown so that HSQL cleans up its mess.
try {
shutdown();
} catch (Throwable t) {
; // we tried, no worries.
}
super.finalize();
}
/**
* Deploys a process.
*/
public Collection<QName> deploy(final File deploymentUnitDirectory) {
__log.info(__msgs.msgDeployStarting(deploymentUnitDirectory));
final Date deployDate = new Date();
// Create the DU and compile/scan it before acquiring lock.
final DeploymentUnitDir du = new DeploymentUnitDir(deploymentUnitDirectory);
try {
du.compile();
} catch (CompilationException ce) {
String errmsg = __msgs.msgDeployFailCompileErrors(ce);
__log.error(errmsg, ce);
throw new ContextException(errmsg, ce);
}
du.scan();
final DeployDocument dd = du.getDeploymentDescriptor();
final ArrayList<ProcessConfImpl> processes = new ArrayList<ProcessConfImpl>();
Collection<QName> deployed;
_rw.writeLock().lock();
// Process and DU use a monotonically increased single version number.
long version = exec(new Callable<Long>() {
public Long call(ConfStoreConnection conn) {
return conn.getNextVersion();
}
});
try {
if (_deploymentUnits.containsKey(du.getName())) {
String errmsg = __msgs.msgDeployFailDuplicateDU(du.getName());
__log.error(errmsg);
throw new ContextException(errmsg);
}
du.setVersion(version);
for (TDeployment.Process processDD : dd.getDeploy().getProcessList()) {
QName pid = toPid(processDD.getName(), version);
// Retires older version if we can find one
DeploymentUnitDir oldDU = findOldDU(du.getName());
if (oldDU != null)
setRetiredPackage(oldDU.getName(), true);
if (_processes.containsKey(pid)) {
String errmsg = __msgs.msgDeployFailDuplicatePID(processDD.getName(), du.getName());
__log.error(errmsg);
throw new ContextException(errmsg);
}
QName type = processDD.getType() != null ? processDD.getType() : processDD.getName();
CBPInfo cbpInfo = du.getCBPInfo(type);
if (cbpInfo == null) {
String errmsg = __msgs.msgDeployFailedProcessNotFound(processDD.getName(), du.getName());
__log.error(errmsg);
throw new ContextException(errmsg);
}
ProcessConfImpl pconf = new ProcessConfImpl(pid, processDD.getName(), version, du, processDD, deployDate,
calcInitialProperties(processDD), calcInitialState(processDD), eprContext, _configDir);
processes.add(pconf);
}
_deploymentUnits.put(du.getName(), du);
for (ProcessConfImpl process : processes) {
__log.info(__msgs.msgProcessDeployed(du.getDeployDir(), process.getProcessId()));
_processes.put(process.getProcessId(), process);
}
} finally {
_rw.writeLock().unlock();
}
// Do the deployment in the DB. We need this so that we remember deployments across system shutdowns.
// We don't fail if there is a DB error, simply print some errors.
deployed = exec(new Callable<Collection<QName>>() {
public Collection<QName> call(ConfStoreConnection conn) {
// Check that this deployment unit is not deployed.
DeploymentUnitDAO dudao = conn.getDeploymentUnit(du.getName());
if (dudao != null) {
String errmsg = "Database out of synch for DU " + du.getName();
__log.warn(errmsg);
dudao.delete();
}
dudao = conn.createDeploymentUnit(du.getName());
try {
dudao.setDeploymentUnitDir(deploymentUnitDirectory.getCanonicalPath());
} catch (IOException e1) {
String errmsg = "Error getting canonical path for " + du.getName()
+ "; deployment unit will not be available after restart!";
__log.error(errmsg);
}
ArrayList<QName> deployed = new ArrayList<QName>();
// Going trough each process declared in the dd
for (ProcessConfImpl pc : processes) {
try {
ProcessConfDAO newDao = dudao.createProcess(pc.getProcessId(), pc.getType(), pc.getVersion());
newDao.setState(pc.getState());
for (Map.Entry<QName, Node> prop : pc.getProcessProperties().entrySet()) {
newDao.setProperty(prop.getKey(), DOMUtils.domToString(prop.getValue()));
}
deployed.add(pc.getProcessId());
conn.setVersion(pc.getVersion());
} catch (Throwable e) {
String errmsg = "Error persisting deployment record for " + pc.getProcessId()
+ "; process will not be available after restart!";
__log.error(errmsg, e);
}
}
return deployed;
}
});
// We want the events to be fired outside of the bounds of the writelock.
try {
for (ProcessConfImpl process : processes) {
fireEvent(new ProcessStoreEvent(ProcessStoreEvent.Type.DEPLOYED, process.getProcessId(), process.getDeploymentUnit()
.getName()));
fireStateChange(process.getProcessId(), process.getState(), process.getDeploymentUnit().getName());
}
} catch (Exception e) {
// A problem at that point means that engine deployment failed, we don't want the store to keep the du
__log.warn("Deployment failed within the engine, store undeploying process.");
undeploy(deploymentUnitDirectory);
if (e instanceof ContextException) throw (ContextException) e;
else throw new ContextException("Deployment failed within the engine.", e);
}
return deployed;
}
public Collection<QName> undeploy(final File dir) {
try {
exec(new Callable<Collection<QName>>() {
public Collection<QName> call(ConfStoreConnection conn) {
DeploymentUnitDAO dudao = conn.getDeploymentUnit(dir.getName());
if (dudao != null)
dudao.delete();
return null;
}
});
} catch (Exception ex) {
__log.error("Error synchronizing with data store; " + dir.getName() + " may be reappear after restart!");
}
Collection<QName> undeployed = Collections.emptyList();
DeploymentUnitDir du;
_rw.writeLock().lock();
try {
du = _deploymentUnits.remove(dir.getName());
if (du != null) {
undeployed = toPids(du.getProcessNames(), du.getVersion());
_processes.keySet().removeAll(undeployed);
}
} finally {
_rw.writeLock().unlock();
}
for (QName pn : undeployed) {
fireEvent(new ProcessStoreEvent(ProcessStoreEvent.Type.UNDEPLOYED, pn, du.getName()));
__log.info(__msgs.msgProcessUndeployed(pn));
}
return undeployed;
}
public Collection<String> getPackages() {
_rw.readLock().lock();
try {
return new ArrayList<String>(_deploymentUnits.keySet());
} finally {
_rw.readLock().unlock();
}
}
public List<QName> listProcesses(String packageName) {
_rw.readLock().lock();
try {
DeploymentUnitDir du = _deploymentUnits.get(packageName);
if (du == null)
return null;
return toPids(du.getProcessNames(), du.getVersion());
} finally {
_rw.readLock().unlock();
}
}
public void setState(final QName pid, final ProcessState state) {
__log.debug("Changing process state for " + pid + " to " + state);
final ProcessConfImpl pconf;
_rw.readLock().lock();
try {
pconf = _processes.get(pid);
if (pconf == null) {
String msg = __msgs.msgProcessNotFound(pid);
__log.info(msg);
throw new ContextException(msg);
}
} finally {
_rw.readLock().unlock();
}
final DeploymentUnitDir dudir = pconf.getDeploymentUnit();
// Update in the database.
ProcessState old = exec(new Callable<ProcessState>() {
public ProcessState call(ConfStoreConnection conn) {
DeploymentUnitDAO dudao = conn.getDeploymentUnit(dudir.getName());
if (dudao == null) {
String errmsg = __msgs.msgProcessNotFound(pid);
__log.error(errmsg);
throw new ContextException(errmsg);
}
ProcessConfDAO dao = dudao.getProcess(pid);
if (dao == null) {
String errmsg = __msgs.msgProcessNotFound(pid);
__log.error(errmsg);
throw new ContextException(errmsg);
}
ProcessState old = dao.getState();
dao.setState(state);
pconf.setState(state);
return old;
}
});
pconf.setState(state);
if (old != null && old != state)
fireStateChange(pid, state, pconf.getDeploymentUnit().getName());
}
public void setRetiredPackage(String packageName, boolean retired) {
DeploymentUnitDir duDir = _deploymentUnits.get(packageName);
if (duDir == null) throw new ContextException("Could not find package " + packageName);
for (QName processName : duDir.getProcessNames()) {
setState(toPid(processName, duDir.getVersion()), retired ? ProcessState.RETIRED : ProcessState.ACTIVE);
}
}
public ProcessConf getProcessConfiguration(final QName processId) {
_rw.readLock().lock();
try {
return _processes.get(processId);
} finally {
_rw.readLock().unlock();
}
}
public void setProperty(final QName pid, final QName propName, final Node value) {
setProperty(pid, propName, DOMUtils.domToStringLevel2(value));
}
public void setProperty(final QName pid, final QName propName, final String value) {
if (__log.isDebugEnabled())
__log.debug("Setting property " + propName + " on process " + pid);
ProcessConfImpl pconf = _processes.get(pid);
if (pconf == null) {
String msg = __msgs.msgProcessNotFound(pid);
__log.info(msg);
throw new ContextException(msg);
}
final DeploymentUnitDir dudir = pconf.getDeploymentUnit();
exec(new ProcessStoreImpl.Callable<Object>() {
public Object call(ConfStoreConnection conn) {
DeploymentUnitDAO dudao = conn.getDeploymentUnit(dudir.getName());
if (dudao == null)
return null;
ProcessConfDAO proc = dudao.getProcess(pid);
if (proc == null)
return null;
proc.setProperty(propName, value);
return null;
}
});
fireEvent(new ProcessStoreEvent(ProcessStoreEvent.Type.PROPERTY_CHANGED, pid, dudir.getName()));
}
/**
* Load all the deployment units out of the store. Called on start-up.
*
*/
public void loadAll() {
final ArrayList<ProcessConfImpl> loaded = new ArrayList<ProcessConfImpl>();
exec(new Callable<Object>() {
public Object call(ConfStoreConnection conn) {
Collection<DeploymentUnitDAO> dus = conn.getDeploymentUnits();
for (DeploymentUnitDAO du : dus)
try {
loaded.addAll(load(du));
} catch (Exception ex) {
__log.error("Error loading DU from store: " + du.getName(), ex);
}
return null;
}
});
for (ProcessConfImpl p : loaded) {
try {
fireStateChange(p.getProcessId(), p.getState(), p.getDeploymentUnit().getName());
} catch (Exception except) {
__log.error("Error while activating process: pid=" + p.getProcessId() + " package="+p.getDeploymentUnit().getName(), except);
}
}
}
public List<QName> getProcesses() {
_rw.readLock().lock();
try {
return new ArrayList<QName>(_processes.keySet());
} finally {
_rw.readLock().unlock();
}
}
public long getCurrentVersion() {
long version = exec(new Callable<Long>() {
public Long call(ConfStoreConnection conn) {
return conn.getNextVersion();
}
});
return version;
}
protected void fireEvent(ProcessStoreEvent pse) {
__log.debug("firing event: " + pse);
for (ProcessStoreListener psl : _listeners)
psl.onProcessStoreEvent(pse);
}
private void fireStateChange(QName processId, ProcessState state, String duname) {
switch (state) {
case ACTIVE:
fireEvent(new ProcessStoreEvent(ProcessStoreEvent.Type.ACTVIATED, processId, duname));
break;
case DISABLED:
fireEvent(new ProcessStoreEvent(ProcessStoreEvent.Type.DISABLED, processId, duname));
break;
case RETIRED:
fireEvent(new ProcessStoreEvent(ProcessStoreEvent.Type.RETIRED, processId, duname));
break;
}
}
public void registerListener(ProcessStoreListener psl) {
__log.debug("Registering listener " + psl);
_listeners.add(psl);
}
public void unregisterListener(ProcessStoreListener psl) {
__log.debug("Unregistering listener " + psl);
_listeners.remove(psl);
}
/**
* Execute database transactions in an isolated context.
*
* @param <T>
* return type
* @param callable
* transaction
* @return
*/
synchronized <T> T exec(Callable<T> callable) {
// We want to submit db jobs to an executor to isolate
// them from the current thread,
Future<T> future = _executor.submit(callable);
try {
return future.get();
} catch (Exception e) {
throw new ContextException("DbError", e);
}
}
private ConfStoreConnection getConnection() {
return _cf.getConnection();
}
/**
* Create a property mapping based on the initial values in the deployment descriptor.
*
* @param dd
* @return
*/
public static Map<QName, Node> calcInitialProperties(TDeployment.Process dd) {
HashMap<QName, Node> ret = new HashMap<QName, Node>();
if (dd.getPropertyList().size() > 0) {
for (TDeployment.Process.Property property : dd.getPropertyList()) {
Element elmtContent = DOMUtils.getElementContent(property.getDomNode());
if (elmtContent != null) {
// We'll need DOM Level 3
Document doc = DOMUtils.newDocument();
doc.appendChild(doc.importNode(elmtContent, true));
ret.put(property.getName(), doc.getDocumentElement());
} else
ret.put(property.getName(), property.getDomNode().getFirstChild());
}
}
return ret;
}
/**
* Figure out the initial process state from the state in the deployment descriptor.
*
* @param dd
* deployment descriptor
* @return
*/
private static ProcessState calcInitialState(TDeployment.Process dd) {
ProcessState state = ProcessState.ACTIVE;
if (dd.isSetActive() && dd.getActive() == false)
state = ProcessState.DISABLED;
if (dd.isSetRetired() && dd.getRetired() == true)
state = ProcessState.RETIRED;
return state;
}
/**
* Load a deployment unit record stored in the db into memory.
*
* @param dudao
*/
protected List<ProcessConfImpl> load(DeploymentUnitDAO dudao) {
__log.debug("Loading deployment unit record from db: " + dudao.getName());
File dudir = findDeployDir(dudao);
if (dudir == null || !dudir.exists())
throw new ContextException("Deployed directory " + (dudir == null ? "(unknown)" : dudir) + " no longer there!");
DeploymentUnitDir dud = new DeploymentUnitDir(dudir);
dud.scan();
ArrayList<ProcessConfImpl> loaded = new ArrayList<ProcessConfImpl>();
_rw.writeLock().lock();
try {
_deploymentUnits.put(dud.getName(), dud);
long version = 0;
for (ProcessConfDAO p : dudao.getProcesses()) {
TDeployment.Process pinfo = dud.getProcessDeployInfo(p.getType());
if (pinfo == null) {
__log.warn("Cannot load " + p.getPID() + "; cannot find descriptor.");
continue;
}
Map<QName, Node> props = calcInitialProperties(pinfo);
// TODO: update the props based on the values in the DB.
ProcessConfImpl pconf = new ProcessConfImpl(p.getPID(), p.getType(), p.getVersion(), dud, pinfo, dudao
.getDeployDate(), props, p.getState(), eprContext, _configDir);
version = p.getVersion();
_processes.put(pconf.getProcessId(), pconf);
loaded.add(pconf);
}
// All processes and the DU have the same version
dud.setVersion(version);
} finally {
_rw.writeLock().unlock();
}
return loaded;
}
protected File findDeployDir(DeploymentUnitDAO dudao) {
File f = new File(dudao.getDeploymentUnitDir());
if (f.exists())
return f;
f = new File(_deployDir, dudao.getName());
if (f.exists())
return f;
return null;
}
/**
* Make sure that the deployment unit is loaded.
*
* @param duName
* deployment unit name
*/
protected boolean load(final String duName) {
_rw.writeLock().lock();
try {
if (_deploymentUnits.containsKey(duName))
return true;
} finally {
_rw.writeLock().unlock();
}
try {
return exec(new Callable<Boolean>() {
public Boolean call(ConfStoreConnection conn) {
DeploymentUnitDAO dudao = conn.getDeploymentUnit(duName);
if (dudao == null)
return false;
load(dudao);
return true;
}
});
} catch (Exception ex) {
__log.error("Error loading deployment unit: " + duName);
return false;
}
}
/**
* Wrapper for database transactions.
*
* @author Maciej Szefler
*
* @param <V>
* return type
*/
abstract class Callable<V> implements java.util.concurrent.Callable<V> {
public V call() {
boolean success = false;
ConfStoreConnection conn = getConnection();
try {
conn.begin();
V r = call(conn);
conn.commit();
success = true;
return r;
} finally {
if (!success)
try {
conn.rollback();
} catch (Exception ex) {
__log.error("DbError", ex);
}
try {
conn.close();
} catch (Exception ex) {
__log.error("DbError", ex);
}
}
}
abstract V call(ConfStoreConnection conn);
}
public void setDeployDir(File depDir) {
if (depDir != null && !depDir.isDirectory())
throw new IllegalArgumentException("Deploy directory is not a directory or does not exist: " + depDir);
_deployDir = depDir;
}
public File getDeployDir() {
return _deployDir;
}
public File getConfigDir() {
return _configDir;
}
public void setConfigDir(File configDir) {
if (configDir != null && !configDir.isDirectory())
throw new IllegalArgumentException("Config directory is not a directory or does not exist: " + configDir);
this._configDir = configDir;
}
public static DataSource createInternalDS(String guid) {
jdbcDataSource hsqlds = new jdbcDataSource();
hsqlds.setDatabase("jdbc:hsqldb:mem:" + guid);
hsqlds.setUser("sa");
hsqlds.setPassword("");
return hsqlds;
}
public static void shutdownInternalDB(DataSource ds) {
try {
ds.getConnection().createStatement().execute("SHUTDOWN;");
} catch (SQLException e) {
__log.error("Error shutting down.", e);
}
}
private List<QName> toPids(Collection<QName> processTypes, long version) {
ArrayList<QName> result = new ArrayList<QName>();
for (QName pqName : processTypes) {
result.add(toPid(pqName, version));
}
return result;
}
private QName toPid(QName processType, long version) {
return new QName(processType.getNamespaceURI(), processType.getLocalPart() + "-" + version);
}
private DeploymentUnitDir findOldDU(String newName) {
DeploymentUnitDir old = null;
int dashIdx = newName.lastIndexOf("-");
if (dashIdx > 0 && dashIdx + 1 < newName.length()) {
String radical = newName.substring(0, dashIdx);
int newVersion = -1;
try {
newVersion = Integer.parseInt(newName.substring(newName.lastIndexOf("-") + 1));
} catch (NumberFormatException e) {
// Swallowing, if we can't parse then we just can't find an old version
}
while (old == null && newVersion >= 0)
old = _deploymentUnits.get(radical + "-" + (newVersion--));
}
return old;
}
private class SimpleThreadFactory implements ThreadFactory {
int threadNumber = 0;
public Thread newThread(Runnable r) {
threadNumber += 1;
Thread t = new Thread(r, "ProcessStoreImpl-"+threadNumber);
t.setDaemon(true);
return t;
}
}
}