Java tutorial
/************************************************************************* * Copyright 2009-2012 Eucalyptus Systems, Inc. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 3 of the License. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * aLong with this program. If not, see http://www.gnu.org/licenses/. * * Please contact Eucalyptus Systems, Inc., 6755 Hollister Ave., Goleta * CA 93117, USA or visit http://www.eucalyptus.com/licenses/ if you need * additional information or have any questions. * * This file may incorporate work covered under the following copyright * and permission notice: * * Software License Agreement (BSD License) * * Copyright (c) 2008, Regents of the University of California * All rights reserved. * * Redistribution and use of this software in source and binary forms, * with or without modification, are permitted provided that the * following conditions are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer * in the documentation and/or other materials provided with the * distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. USERS OF THIS SOFTWARE ACKNOWLEDGE * THE POSSIBLE PRESENCE OF OTHER OPEN SOURCE LICENSED MATERIAL, * COPYRIGHTED MATERIAL OR PATENTED MATERIAL IN THIS SOFTWARE, * AND IF ANY SUCH MATERIAL IS DISCOVERED THE PARTY DISCOVERING * IT MAY INFORM DR. RICH WOLSKI AT THE UNIVERSITY OF CALIFORNIA, * SANTA BARBARA WHO WILL THEN ASCERTAIN THE MOST APPROPRIATE REMEDY, * WHICH IN THE REGENTS' DISCRETION MAY INCLUDE, WITHOUT LIMITATION, * REPLACEMENT OF THE CODE SO IDENTIFIED, LICENSING OF THE CODE SO * IDENTIFIED, OR WITHDRAWAL OF THE CODE CAPABILITY TO THE EXTENT * NEEDED TO COMPLY WITH ANY SUCH LICENSES OR RIGHTS. ************************************************************************/ package com.eucalyptus.blockstorage; import java.util.concurrent.Callable; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.TimeUnit; import java.util.concurrent.TimeoutException; import java.util.concurrent.locks.ReadWriteLock; import java.util.concurrent.locks.ReentrantReadWriteLock; import java.util.regex.Matcher; import java.util.regex.Pattern; import javax.annotation.Nonnull; import org.apache.commons.lang.StringUtils; import org.apache.log4j.Logger; import com.eucalyptus.blockstorage.entities.DirectStorageInfo; import com.eucalyptus.blockstorage.util.StorageProperties; import com.eucalyptus.component.Faults; import com.eucalyptus.util.EucalyptusCloudException; import com.google.common.base.Joiner; import com.google.common.base.Splitter; import edu.ucsb.eucalyptus.util.StreamConsumer; import edu.ucsb.eucalyptus.util.SystemUtil; import edu.ucsb.eucalyptus.util.SystemUtil.CommandOutput; /** * Wraps calls to TGT for handling timeouts and error codes * Cannot always trust TGT error codes for failure status. Most calls also check the error stream. * */ public class TGTWrapper { private static final String TGTADM = "tgtadm"; final public static String TGT_SERVICE_NAME = "tgtd"; final private static Logger LOG = Logger.getLogger(TGTWrapper.class); final private static String ROOT_WRAP = StorageProperties.EUCA_ROOT_WRAPPER; private static final ReadWriteLock serviceLock = new ReentrantReadWriteLock(); private static ExecutorService service; // do not access directly, use getExecutor / getExecutorWithInit final private static int RESOURCE_NOT_FOUND = 22; //The tgt return code for resource not found. // TODO define fault IDs in a enum private static final int TGT_HOSED = 2000; private static final int TGT_CORRUPTED = 2002; private static final Joiner JOINER = Joiner.on(" ").skipNulls(); private static final Splitter LINE_SPLITTER = Splitter.on('\n').omitEmptyStrings().trimResults(); private static final Pattern LUN_PATTERN = Pattern.compile("\\s*LUN:\\s*(\\d+)\\s*"); private static final Pattern TARGET_PATTERN = Pattern.compile("\\s*Target\\s*(\\d+):\\s+(\\S+)\\s*"); private static final Pattern RESOURCE_PATTERN = Pattern.compile("\\s*Backing store path:\\s*(\\S+)\\s*"); public static class ResourceNotFoundException extends EucalyptusCloudException { private static final Long serialVersionUID = 1L; public ResourceNotFoundException() { super("Resource not found"); } public ResourceNotFoundException(String resource) { super("Resource " + resource + " not found"); } } public static class OperationFailedException extends EucalyptusCloudException { private static final Long serialVersionUID = 1L; private int errorCode = -1; private String outputContent = null; private String errorContent = null; public OperationFailedException() { super("TGT operation failed"); } public OperationFailedException(String message) { super("TGT operation failed: " + message); } public OperationFailedException(String operation, String message) { super("TGT operation " + operation + " failed: " + message); } public OperationFailedException(String output, String errorOutput, int errorCode) { super("TGT operation failed"); this.outputContent = output; this.errorCode = errorCode; this.errorContent = errorOutput; } public OperationFailedException(EucalyptusCloudException e) { super(e); } public int getErrorCode() { return errorCode; } public void setErrorCode(int errorCode) { this.errorCode = errorCode; } public String getOutputContent() { return outputContent; } public void setOutput(String output) { this.outputContent = output; } public String getErrorContent() { return errorContent; } public void setErrorContent(String errorOutput) { this.errorContent = errorOutput; } } public static class CallTimeoutException extends EucalyptusCloudException { private static final long serialVersionUID = 1L; public CallTimeoutException() { super("Call timed out"); } public CallTimeoutException(String command) { super("Call timed for " + command); } } /** * Idempotent start */ public static void start() { serviceLock.writeLock().lock(); try { if (service == null) { service = Executors.newFixedThreadPool(10); } } finally { serviceLock.writeLock().unlock(); } } public static void stop() { serviceLock.writeLock().lock(); try { ExecutorService toShutdown = service; service = null; toShutdown.shutdownNow(); } catch (Exception e) { LOG.warn("Unable to shutdown thread pool", e); } finally { serviceLock.writeLock().unlock(); } } private static ExecutorService getExecutor() { serviceLock.readLock().lock(); try { if (service == null) { throw new IllegalStateException("Not started"); } return service; } finally { serviceLock.readLock().unlock(); } } private static ExecutorService getExecutorWithInit() { ExecutorService service; try { service = getExecutor(); } catch (IllegalStateException e) { start(); service = getExecutor(); } return service; } /** * Separate thread to wait for {@link java.lang.Process Process} to * complete and return its exit value * */ public static class ProcessMonitor implements Callable<Integer> { private Process process; ProcessMonitor(Process process) { this.process = process; } public Integer call() throws Exception { process.waitFor(); return process.exitValue(); } } // Implementation of EUCA-3597 /** * executeTGTs the specified tgt command in a separate process. * A {@link DirectStorageInfo#timeoutInMillis timeout} is enforced on * the process using {@link java.util.concurrent.ExecutorService ExecutorService} * framework. If the process does not complete with in the timeout, it is cancelled. * * @param command * @param timeout * @return CommandOutput * @throws EucalyptusCloudException */ private static CommandOutput execute(@Nonnull String[] command, @Nonnull Long timeout) throws EucalyptusCloudException, CallTimeoutException { try { Integer returnValue = -999999; Runtime runtime = Runtime.getRuntime(); Process process = runtime.exec(command); StreamConsumer error = new StreamConsumer(process.getErrorStream()); StreamConsumer output = new StreamConsumer(process.getInputStream()); error.start(); output.start(); Callable<Integer> processMonitor = new ProcessMonitor(process); Future<Integer> processController = getExecutorWithInit().submit(processMonitor); try { returnValue = processController.get(timeout, TimeUnit.MILLISECONDS); } catch (TimeoutException tex) { String commandStr = buildCommand(command); LOG.error(commandStr + " timed out. Cancelling the process, logging a fault and exceptioning out"); processController.cancel(true); Faults.forComponent(Storage.class).havingId(TGT_HOSED).withVar("component", "Storage Controller") .withVar("timeout", Long.toString(timeout)).log(); throw new CallTimeoutException("No response from the command " + commandStr + ". Process timed out after waiting for " + timeout + " milliseconds"); } output.join(); error.join(); LOG.debug("TGTWrapper executed: " + JOINER.join(command) + "\n return=" + returnValue + "\n stdout=" + output.getReturnValue() + "\n stderr=" + error.getReturnValue()); return new CommandOutput(returnValue, output.getReturnValue(), error.getReturnValue()); } catch (CallTimeoutException e) { throw e; } catch (Exception ex) { throw new EucalyptusCloudException(ex); } } /** * Calls exclusively for TGT commands, does some analysis of return code and error stream to send better exceptions * @param command * @param timeout * @return * * @throws CallTimeoutException * @throws OperationFailedException * @throws ResourceNotFoundException */ private static CommandOutput executeTGT(@Nonnull String[] command, @Nonnull Long timeout) throws OperationFailedException, CallTimeoutException, ResourceNotFoundException { CommandOutput output = null; try { output = execute(command, timeout); } catch (ResourceNotFoundException e) { throw e; } catch (CallTimeoutException e) { throw e; } catch (EucalyptusCloudException e) { throw new OperationFailedException(e); } if (output.returnValue == 22) { if (output.error.contains("target")) throw new ResourceNotFoundException("target"); if (output.error.contains("account")) throw new ResourceNotFoundException("account"); if (output.error.contains("logicalunit")) throw new ResourceNotFoundException("logicalunit"); throw new ResourceNotFoundException(); } return output; } private static String buildCommand(@Nonnull String[] command) { StringBuilder builder = new StringBuilder(); for (String part : command) { builder.append(part).append(' '); } return builder.toString(); } /** * Runs pre-checks for startup etc. * @param timeout * @throws EucalyptusCloudException */ public static void precheckService(Long timeout) throws EucalyptusCloudException { CommandOutput output = null; output = execute(new String[] { ROOT_WRAP, "tgtadm", "--help" }, timeout); if (output.returnValue != 0 || StringUtils.isNotBlank(output.error)) { Faults.forComponent(Storage.class).havingId(TGT_CORRUPTED).withVar("component", "Storage Controller") .withVar("operation", "tgtadm --help").withVar("error", output.error).log(); throw new EucalyptusCloudException("tgtadm not found: Is tgt installed?"); } output = execute(new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--mode", "target", "--op", "show" }, timeout); if (output.returnValue != 0 || StringUtils.isNotBlank(output.error)) { LOG.warn("Unable to connect to tgt daemon. Is tgtd loaded?"); LOG.info("Attempting to start tgtd ISCSI daemon"); output = execute(new String[] { ROOT_WRAP, "service", TGT_SERVICE_NAME, "status" }, timeout); if (output.returnValue != 0 || StringUtils.isNotBlank(output.error)) { output = execute(new String[] { ROOT_WRAP, "service", TGT_SERVICE_NAME, "start" }, timeout); if (output.returnValue != 0 || StringUtils.isNotBlank(output.error)) { Faults.forComponent(Storage.class).havingId(TGT_CORRUPTED) .withVar("component", "Storage Controller").withVar("operation", "service tgt start") .withVar("error", output.error).log(); throw new EucalyptusCloudException("Unable to start tgt daemon. Cannot proceed."); } } else { output = execute(new String[] { ROOT_WRAP, "service", "tgt", "start" }, timeout); if (output.returnValue != 0 || StringUtils.isNotBlank(output.error)) { Faults.forComponent(Storage.class).havingId(TGT_CORRUPTED) .withVar("component", "Storage Controller").withVar("operation", "service tgt start") .withVar("error", output.error).log(); throw new EucalyptusCloudException("Unable to start tgt daemon. Cannot proceed."); } } } } /** * Runs a service check on TGT. * @param timeout * @throws EucalyptusCloudException */ public static void checkService(Long timeout) throws EucalyptusCloudException { try { CommandOutput output = execute(new String[] { ROOT_WRAP, "service", TGT_SERVICE_NAME, "status" }, timeout); if (StringUtils.isNotBlank(output.error)) { Faults.forComponent(Storage.class).havingId(TGT_CORRUPTED) .withVar("component", "Storage Controller").withVar("operation", "service tgt status") .withVar("error", output.error).log(); throw new EucalyptusCloudException("tgt service check failed with error: " + output.error); } } catch (CallTimeoutException e) { LOG.error("Call timed out checking service.", e); throw e; } catch (EucalyptusCloudException e) { LOG.error("Check service failed", e); throw e; } } /** * Creates a new target with the given name and target ID * @param volumeId * @param tid * @param name * @param timeout * @return true on success, false on failure * @throws CallTimeoutException * @throws EucalyptusCloudException */ public static void createTarget(@Nonnull String volumeId, int tid, @Nonnull String name, @Nonnull Long timeout) throws CallTimeoutException, OperationFailedException, ResourceNotFoundException { CommandOutput output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "new", "--mode", "target", "--tid", String.valueOf(tid), "-T", name }, timeout); if (output.failed() || StringUtils.isNotBlank(output.error)) { throw new OperationFailedException(output.output, output.error, output.returnValue); } } /** * Removes the target from TGT, only operates on the given target * * @param volumeId * @param tid * @param timeout * @param force * @return * @throws EucalyptusCloudException */ public static void deleteTarget(@Nonnull String volumeId, int tid, @Nonnull Long timeout, boolean force) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { LOG.debug("Tearing down target " + tid + " for volume " + volumeId); CommandOutput output = null; if (force) { output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "delete", "--mode", "target", "--tid", String.valueOf(tid), "--force" }, timeout); } else { output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "delete", "--mode", "target", "--tid", String.valueOf(tid) }, timeout); } if (output.failed() || StringUtils.isNotBlank(output.error)) { throw new OperationFailedException(output.output, output.error, output.returnValue); } } /** * Creates a lun in the given target that is backed by the resource in resourcePath (file/block device) * @param volumeId * @param tid * @param lun * @param resourcePath * @param timeout * @throws ResourceNotFoundException * @throws CallTimeoutException * @throws EucalyptusCloudException */ public static void createLun(@Nonnull String volumeId, int tid, int lun, @Nonnull String resourcePath, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { CommandOutput output = executeTGT( new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "new", "--mode", "logicalunit", "--tid", String.valueOf(tid), "--lun", String.valueOf(lun), "-b", resourcePath }, timeout); if (output.failed() || StringUtils.isNotBlank(output.error)) { if (output.returnValue == 22) { throw new ResourceNotFoundException(String.valueOf(tid)); } throw new OperationFailedException("Create lun operation failed"); } } /** * Removes the target from TGT, only operates on the given target * @param volumeId * @param tid * @param lun * @param timeout */ public static void deleteLun(@Nonnull String volumeId, int tid, int lun, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { LOG.debug("Removing LUN " + lun + " from target " + tid + " for volume " + volumeId); CommandOutput output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "delete", "--mode", "logicalunit", "--tid", String.valueOf(tid), "--lun", String.valueOf(lun) }, timeout); if (output.failed() || StringUtils.isNotBlank(output.error)) { //If the logical unit is not found, return true, since it is not in the target. if (output.returnValue == RESOURCE_NOT_FOUND && output.error.contains("can't find the logical unit")) { LOG.debug("Volume: " + volumeId + " logical unit already removed."); } throw new OperationFailedException("Delete lun operation failed"); } } /** * Binds a chap user/account to the target, requiring initiators to use chap to connect * @param volumeId * @param user * @param tid * @param timeout * @throws ResourceNotFoundException * @throws CallTimeoutException * @throws EucalyptusCloudException */ public static void bindUser(@Nonnull String volumeId, @Nonnull String user, int tid, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { CommandOutput output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "bind", "--mode", "account", "--tid", String.valueOf(tid), "--user", user }, timeout); if (output.failed() || StringUtils.isNotBlank(output.error)) { if (output.returnValue == 22 && output.error.contains("account")) { throw new ResourceNotFoundException(user); } else if (output.returnValue == 22 && output.error.contains("target")) { throw new ResourceNotFoundException("Target " + String.valueOf(tid)); } throw new OperationFailedException("Bind user operation failed"); } } /** * Binds the target to all host initiators (permits connections) * @param volumeId * @param tid * @param timeout * @return * @throws ResourceNotFoundException * @throws CallTimeoutException * @throws EucalyptusCloudException */ public static void bindTarget(@Nonnull String volumeId, int tid, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { try { CommandOutput output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "bind", "--mode", "target", "--tid", String.valueOf(tid), "-I", "ALL" }, timeout); } catch (EucalyptusCloudException e) { } } /** * Unbinds all initiators from the given target. * @param volumeId * @param tid * @param lun * @param timeout * @return */ public static void unbindTarget(String volumeId, int tid, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { LOG.debug("Unbinding target " + tid + " for volume " + volumeId); CommandOutput output = executeTGT(new String[] { ROOT_WRAP, TGTADM, "--lld", "iscsi", "--op", "unbind", "--mode", "target", "--tid", String.valueOf(tid), "-I", "ALL" }, timeout); if (output.failed() || StringUtils.isNotBlank(output.error)) { if (output.returnValue == RESOURCE_NOT_FOUND && output.error.contains("can't find the target")) { LOG.debug("Volume: " + volumeId + " target not found, cannot unbind, returning unbind success."); throw new ResourceNotFoundException("target " + tid); } LOG.error("Volume: " + volumeId + " Unable to unbind tid: " + tid); throw new OperationFailedException(output.output, output.error, output.returnValue); } } /** * Checks if the target exists. If resource is not null then returns true iff the target exists, and exports a lun backed * by the specified resource. A LUN id check is not done, any LUN in the target will match. * @param volumeId * @param tid * @param resource the backing resource. If null just the tid is checked, otherwise both the tid and resource are checked * @param timeout * @return */ public static boolean targetExists(@Nonnull String volumeId, int tid, String resource, @Nonnull Long timeout) throws EucalyptusCloudException { try { CommandOutput output = executeTGT(new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--op", "show", "--mode", "target", "--tid", String.valueOf(tid) }, timeout); if (StringUtils.isBlank(output.error)) { if (resource != null) { output = executeTGT(new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--op", "show", "--mode", "target" }, timeout); return hasResource(output.output, tid, resource); } else { LOG.debug("Volume " + volumeId + " check for target " + tid + " returning true. Target exists"); return true; } } else { LOG.debug("Volume: " + volumeId + " Target: " + tid + " not found"); } } catch (ResourceNotFoundException e) { //Fall through, return false } catch (EucalyptusCloudException e) { //This case includes call timeouts LOG.error("Caught unexpected exception checking for target existence for volume " + volumeId, e); throw e; } return false; } /** * Returns true if target found had the requested lun * @param volumeId * @param tid * @param lun * @param timeout * @return * @throws EucalyptusCloudException */ public static boolean targetHasLun(@Nonnull String volumeId, int tid, int lun, @Nonnull Long timeout) throws EucalyptusCloudException { try { CommandOutput output = executeTGT(new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--op", "show", "--mode", "target", "--tid", String.valueOf(tid) }, timeout); output = executeTGT( new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--op", "show", "--mode", "target" }, timeout); return hasLun(output.output, tid, lun); } catch (ResourceNotFoundException e) { //Fall through, return false } catch (EucalyptusCloudException e) { //This case includes call timeouts LOG.error("Caught unexpected exception checking for target existence for volume " + volumeId, e); throw e; } return false; } /** * Check the output for the given resource string, but only if the tid matches * @param output * @param resource * @return */ private static boolean hasResource(@Nonnull String output, int tid, @Nonnull String resource) { Matcher targetMatcher = null; Matcher resourceMatcher = null; String target = null; for (String line : LINE_SPLITTER.split(output)) { targetMatcher = TARGET_PATTERN.matcher(line); if (targetMatcher.matches()) { target = targetMatcher.group(1); if (Integer.parseInt(targetMatcher.group(1)) != tid) { target = null; continue; } } else { if (target != null) { //Only try lun match if found the target we're looking for resourceMatcher = RESOURCE_PATTERN.matcher(line); if (resourceMatcher.matches() && resourceMatcher.group(1).equals(resource)) { return true; } } } } return false; } /** * Check the output for the given lun * @param output * @param lun * @param tid the target to look in * @return */ private static boolean hasLun(@Nonnull String output, int tid, int lun) { Matcher targetMatcher = null; Matcher lunMatcher = null; String target = null; for (String line : LINE_SPLITTER.split(output)) { targetMatcher = TARGET_PATTERN.matcher(line); if (targetMatcher.matches()) { target = targetMatcher.group(1); if (Integer.parseInt(targetMatcher.group(1)) != tid) { target = null; continue; } } else { if (target != null) { //Only try lun match if found the target we're looking for lunMatcher = LUN_PATTERN.matcher(line); if (lunMatcher.matches() && lunMatcher.group(1).equals(String.valueOf(lun))) { return true; } } } } return false; } public static void addUser(@Nonnull String username, @Nonnull String password, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { executeTGT(new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--op", "new", "--mode", "account", "--user", username, "--password", password }, timeout); } public static void deleteUser(@Nonnull String username, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { executeTGT(new String[] { ROOT_WRAP, "tgtadm", "--lld", "iscsi", "--op", "delete", "--mode", "account", "--user", username }, timeout); } public static boolean userExists(@Nonnull String username, @Nonnull Long timeout) throws OperationFailedException, ResourceNotFoundException, CallTimeoutException { CommandOutput output = executeTGT(new String[] { ROOT_WRAP, "tgtadm", "--op", "show", "--mode", "account" }, timeout); String returnValue = output.output; if (returnValue.length() > 0) { Pattern p = Pattern.compile(username); Matcher m = p.matcher(returnValue); if (m.find()) return true; else return false; } return false; } }