hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/fair/allocation/AllocationFileQueueParser.java - hadoop - 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.hadoop.yarn.server.resourcemanager.scheduler.fair.allocation;

 import org.apache.hadoop.security.authorize.AccessControlList;
 import org.apache.hadoop.yarn.api.records.QueueACL;
 import org.apache.hadoop.yarn.api.records.ReservationACL;
 import org.apache.hadoop.yarn.api.records.Resource;
 import org.apache.hadoop.yarn.security.AccessType;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerUtils;
 import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.*;
 import org.apache.hadoop.yarn.util.resource.Resources;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.w3c.dom.Element;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.w3c.dom.Text;

 import java.util.List;
 import java.util.Map;

 /**
  * Responsible for loading queue configuration properties
  * from a list of {@link Element}s containing queues.
  */
 public class AllocationFileQueueParser {
   private static final Logger LOG =
       LoggerFactory.getLogger(AllocationFileQueueParser.class);

   public static final String ROOT = "root";
   public static final AccessControlList EVERYBODY_ACL =
       new AccessControlList("*");
   static final AccessControlList NOBODY_ACL = new AccessControlList(" ");
   private static final String MIN_RESOURCES = "minResources";
   private static final String MAX_RESOURCES = "maxResources";
   private static final String MAX_CHILD_RESOURCES = "maxChildResources";
   private static final String MAX_RUNNING_APPS = "maxRunningApps";
   private static final String MAX_AMSHARE = "maxAMShare";
   public static final String MAX_CONTAINER_ALLOCATION =
       "maxContainerAllocation";
   private static final String WEIGHT = "weight";
   private static final String MIN_SHARE_PREEMPTION_TIMEOUT =
       "minSharePreemptionTimeout";
   private static final String FAIR_SHARE_PREEMPTION_TIMEOUT =
       "fairSharePreemptionTimeout";
   private static final String FAIR_SHARE_PREEMPTION_THRESHOLD =
       "fairSharePreemptionThreshold";
   private static final String SCHEDULING_POLICY = "schedulingPolicy";
   private static final String SCHEDULING_MODE = "schedulingMode";
   private static final String ACL_SUBMIT_APPS = "aclSubmitApps";
   private static final String ACL_ADMINISTER_APPS = "aclAdministerApps";
   private static final String ACL_ADMINISTER_RESERVATIONS =
       "aclAdministerReservations";
   private static final String ACL_LIST_RESERVATIONS = "aclListReservations";
   private static final String ACL_SUBMIT_RESERVATIONS = "aclSubmitReservations";
   private static final String RESERVATION = "reservation";
   private static final String ALLOW_PREEMPTION_FROM = "allowPreemptionFrom";
   private static final String QUEUE = "queue";
   private static final String POOL = "pool";

   private final List<Element> elements;

   public AllocationFileQueueParser(List<Element> elements) {
     this.elements = elements;
   }

   // Load queue elements. A root queue can either be included or omitted. If
   // it's included, all other queues must be inside it.
   public QueueProperties parse() throws AllocationConfigurationException {
     QueueProperties.Builder queuePropertiesBuilder =
         new QueueProperties.Builder();
     for (Element element : elements) {
       String parent = ROOT;
       if (element.getAttribute("name").equalsIgnoreCase(ROOT)) {
         if (elements.size() > 1) {
           throw new AllocationConfigurationException(
               "If configuring root queue,"
                   + " no other queues can be placed alongside it.");
         }
         parent = null;
       }
       loadQueue(parent, element, queuePropertiesBuilder);
     }

     return queuePropertiesBuilder.build();
   }

   /**
    * Loads a queue from a queue element in the configuration file.
    */
   private void loadQueue(String parentName, Element element,
       QueueProperties.Builder builder) throws AllocationConfigurationException {
     String queueName =
         FairSchedulerUtilities.trimQueueName(element.getAttribute("name"));

     if (queueName.contains(".")) {
       throw new AllocationConfigurationException("Bad fair scheduler config "
           + "file: queue name (" + queueName + ") shouldn't contain period.");
     }

     if (queueName.isEmpty()) {
       throw new AllocationConfigurationException("Bad fair scheduler config "
           + "file: queue name shouldn't be empty or "
           + "consist only of whitespace.");
     }

     if (parentName != null) {
       queueName = parentName + "." + queueName;
     }

     NodeList fields = element.getChildNodes();
     boolean isLeaf = true;
     boolean isReservable = false;
     boolean isMaxAMShareSet = false;

     for (int j = 0; j < fields.getLength(); j++) {
       Node fieldNode = fields.item(j);
       if (!(fieldNode instanceof Element)) {
         continue;
       }
       Element field = (Element) fieldNode;
       if (MIN_RESOURCES.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         ConfigurableResource val =
             FairSchedulerConfiguration.parseResourceConfigValue(text, 0L);
         builder.minQueueResources(queueName, val.getResource());
       } else if (MAX_RESOURCES.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         ConfigurableResource val =
             FairSchedulerConfiguration.parseResourceConfigValue(text);
         builder.maxQueueResources(queueName, val);
       } else if (MAX_CHILD_RESOURCES.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         ConfigurableResource val =
             FairSchedulerConfiguration.parseResourceConfigValue(text);
         builder.maxChildQueueResources(queueName, val);
       } else if (MAX_RUNNING_APPS.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         int val = Integer.parseInt(text);
         builder.queueMaxApps(queueName, val);
       } else if (MAX_AMSHARE.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         float val = Float.parseFloat(text);
         val = Math.min(val, 1.0f);
         builder.queueMaxAMShares(queueName, val);
         isMaxAMShareSet = true;
       } else if (MAX_CONTAINER_ALLOCATION.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         ConfigurableResource val =
             FairSchedulerConfiguration.parseResourceConfigValue(text);
         builder.queueMaxContainerAllocation(queueName, val.getResource());
       } else if (WEIGHT.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         double val = Double.parseDouble(text);
         builder.queueWeights(queueName, (float) val);
       } else if (MIN_SHARE_PREEMPTION_TIMEOUT.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         long val = Long.parseLong(text) * 1000L;
         builder.minSharePreemptionTimeouts(queueName, val);
       } else if (FAIR_SHARE_PREEMPTION_TIMEOUT.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         long val = Long.parseLong(text) * 1000L;
         builder.fairSharePreemptionTimeouts(queueName, val);
       } else if (FAIR_SHARE_PREEMPTION_THRESHOLD.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         float val = Float.parseFloat(text);
         val = Math.max(Math.min(val, 1.0f), 0.0f);
         builder.fairSharePreemptionThresholds(queueName, val);
       } else if (SCHEDULING_POLICY.equals(field.getTagName())
           || SCHEDULING_MODE.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         SchedulingPolicy policy = SchedulingPolicy.parse(text);
         builder.queuePolicies(queueName, policy);
       } else if (ACL_SUBMIT_APPS.equals(field.getTagName())) {
         String text = ((Text) field.getFirstChild()).getData();
         builder.queueAcls(queueName, AccessType.SUBMIT_APP,
             new AccessControlList(text));
       } else if (ACL_ADMINISTER_APPS.equals(field.getTagName())) {
         String text = ((Text) field.getFirstChild()).getData();
         builder.queueAcls(queueName, AccessType.ADMINISTER_QUEUE,
             new AccessControlList(text));
       } else if (ACL_ADMINISTER_RESERVATIONS.equals(field.getTagName())) {
         String text = ((Text) field.getFirstChild()).getData();
         builder.reservationAcls(queueName,
             ReservationACL.ADMINISTER_RESERVATIONS,
             new AccessControlList(text));
       } else if (ACL_LIST_RESERVATIONS.equals(field.getTagName())) {
         String text = ((Text) field.getFirstChild()).getData();
         builder.reservationAcls(queueName, ReservationACL.LIST_RESERVATIONS,
             new AccessControlList(text));
       } else if (ACL_SUBMIT_RESERVATIONS.equals(field.getTagName())) {
         String text = ((Text) field.getFirstChild()).getData();
         builder.reservationAcls(queueName, ReservationACL.SUBMIT_RESERVATIONS,
             new AccessControlList(text));
       } else if (RESERVATION.equals(field.getTagName())) {
         isReservable = true;
         builder.reservableQueues(queueName);
         builder.configuredQueues(FSQueueType.PARENT, queueName);
       } else if (ALLOW_PREEMPTION_FROM.equals(field.getTagName())) {
         String text = getTrimmedTextData(field);
         if (!Boolean.parseBoolean(text)) {
           builder.nonPreemptableQueues(queueName);
         }
       } else if (QUEUE.endsWith(field.getTagName())
           || POOL.equals(field.getTagName())) {
         loadQueue(queueName, field, builder);
         isLeaf = false;
       }
     }
     // if a leaf in the alloc file is marked as type='parent'
     // then store it as a parent queue
     if (isLeaf && !"parent".equals(element.getAttribute("type"))) {
       // reservable queue has been already configured as parent
       if (!isReservable) {
         builder.configuredQueues(FSQueueType.LEAF, queueName);
       }
     } else {
       if (isReservable) {
         throw new AllocationConfigurationException(
             getErrorString(queueName, RESERVATION));
       } else if (isMaxAMShareSet) {
         throw new AllocationConfigurationException(
             getErrorString(queueName, MAX_AMSHARE));
       }
       builder.configuredQueues(FSQueueType.PARENT, queueName);
     }

     // Set default acls if not defined
     // The root queue defaults to all access
     for (QueueACL acl : QueueACL.values()) {
       AccessType accessType = SchedulerUtils.toAccessType(acl);
       if (!builder.isAclDefinedForAccessType(queueName, accessType)) {
         AccessControlList defaultAcl =
             queueName.equals(ROOT) ? EVERYBODY_ACL : NOBODY_ACL;
         builder.queueAcls(queueName, accessType, defaultAcl);
       }
     }

     checkMinAndMaxResource(builder.getMinQueueResources(),
         builder.getMaxQueueResources(), queueName);
   }

   /**
    * Set up the error string based on the supplied parent queueName and element.
    * @param parentQueueName the parent queue name.
    * @param element the element that should not be present for the parent queue.
    * @return the error string.
    */
   private String getErrorString(String parentQueueName, String element) {
     return "The configuration settings"
         + " for " + parentQueueName + " are invalid. A queue element that "
         + "contains child queue elements or that has the type='parent' "
         + "attribute cannot also include a " + element + " element.";
   }

   private String getTrimmedTextData(Element element) {
     return ((Text) element.getFirstChild()).getData().trim();
   }

   private void checkMinAndMaxResource(Map<String, Resource> minResources,
       Map<String, ConfigurableResource> maxResources, String queueName) {

     ConfigurableResource maxConfigurableResource = maxResources.get(queueName);
     Resource minResource = minResources.get(queueName);

     if (maxConfigurableResource != null && minResource != null) {
       Resource maxResource = maxConfigurableResource.getResource();

       // check whether max resource is greater or equals to min resource when
       // max resource are absolute values
       if (maxResource != null && !Resources.fitsIn(minResource, maxResource)) {
         LOG.warn(String.format(
             "Queue %s has max resources %s less than " + "min resources %s",
             queueName, maxResource, minResource));
       }
     }
   }
 }
	/*
	* 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.hadoop.yarn.server.resourcemanager.scheduler.fair.allocation;

	import org.apache.hadoop.security.authorize.AccessControlList;
	import org.apache.hadoop.yarn.api.records.QueueACL;
	import org.apache.hadoop.yarn.api.records.ReservationACL;
	import org.apache.hadoop.yarn.api.records.Resource;
	import org.apache.hadoop.yarn.security.AccessType;
	import org.apache.hadoop.yarn.server.resourcemanager.scheduler.SchedulerUtils;
	import org.apache.hadoop.yarn.server.resourcemanager.scheduler.fair.*;
	import org.apache.hadoop.yarn.util.resource.Resources;
	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;
	import org.w3c.dom.Element;
	import org.w3c.dom.Node;
	import org.w3c.dom.NodeList;
	import org.w3c.dom.Text;

	import java.util.List;
	import java.util.Map;

	/**
	* Responsible for loading queue configuration properties
	* from a list of {@link Element}s containing queues.
	*/
	public class AllocationFileQueueParser {
	private static final Logger LOG =
	LoggerFactory.getLogger(AllocationFileQueueParser.class);

	public static final String ROOT = "root";
	public static final AccessControlList EVERYBODY_ACL =
	new AccessControlList("*");
	static final AccessControlList NOBODY_ACL = new AccessControlList(" ");
	private static final String MIN_RESOURCES = "minResources";
	private static final String MAX_RESOURCES = "maxResources";
	private static final String MAX_CHILD_RESOURCES = "maxChildResources";
	private static final String MAX_RUNNING_APPS = "maxRunningApps";
	private static final String MAX_AMSHARE = "maxAMShare";
	public static final String MAX_CONTAINER_ALLOCATION =
	"maxContainerAllocation";
	private static final String WEIGHT = "weight";
	private static final String MIN_SHARE_PREEMPTION_TIMEOUT =
	"minSharePreemptionTimeout";
	private static final String FAIR_SHARE_PREEMPTION_TIMEOUT =
	"fairSharePreemptionTimeout";
	private static final String FAIR_SHARE_PREEMPTION_THRESHOLD =
	"fairSharePreemptionThreshold";
	private static final String SCHEDULING_POLICY = "schedulingPolicy";
	private static final String SCHEDULING_MODE = "schedulingMode";
	private static final String ACL_SUBMIT_APPS = "aclSubmitApps";
	private static final String ACL_ADMINISTER_APPS = "aclAdministerApps";
	private static final String ACL_ADMINISTER_RESERVATIONS =
	"aclAdministerReservations";
	private static final String ACL_LIST_RESERVATIONS = "aclListReservations";
	private static final String ACL_SUBMIT_RESERVATIONS = "aclSubmitReservations";
	private static final String RESERVATION = "reservation";
	private static final String ALLOW_PREEMPTION_FROM = "allowPreemptionFrom";
	private static final String QUEUE = "queue";
	private static final String POOL = "pool";

	private final List<Element> elements;

	public AllocationFileQueueParser(List<Element> elements) {
	this.elements = elements;
	}

	// Load queue elements. A root queue can either be included or omitted. If
	// it's included, all other queues must be inside it.
	public QueueProperties parse() throws AllocationConfigurationException {
	QueueProperties.Builder queuePropertiesBuilder =
	new QueueProperties.Builder();
	for (Element element : elements) {
	String parent = ROOT;
	if (element.getAttribute("name").equalsIgnoreCase(ROOT)) {
	if (elements.size() > 1) {
	throw new AllocationConfigurationException(
	"If configuring root queue,"
	+ " no other queues can be placed alongside it.");
	}
	parent = null;
	}
	loadQueue(parent, element, queuePropertiesBuilder);
	}

	return queuePropertiesBuilder.build();
	}

	/**
	* Loads a queue from a queue element in the configuration file.
	*/
	private void loadQueue(String parentName, Element element,
	QueueProperties.Builder builder) throws AllocationConfigurationException {
	String queueName =
	FairSchedulerUtilities.trimQueueName(element.getAttribute("name"));

	if (queueName.contains(".")) {
	throw new AllocationConfigurationException("Bad fair scheduler config "
	+ "file: queue name (" + queueName + ") shouldn't contain period.");
	}

	if (queueName.isEmpty()) {
	throw new AllocationConfigurationException("Bad fair scheduler config "
	+ "file: queue name shouldn't be empty or "
	+ "consist only of whitespace.");
	}

	if (parentName != null) {
	queueName = parentName + "." + queueName;
	}

	NodeList fields = element.getChildNodes();
	boolean isLeaf = true;
	boolean isReservable = false;
	boolean isMaxAMShareSet = false;

	for (int j = 0; j < fields.getLength(); j++) {
	Node fieldNode = fields.item(j);
	if (!(fieldNode instanceof Element)) {
	continue;
	}
	Element field = (Element) fieldNode;
	if (MIN_RESOURCES.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	ConfigurableResource val =
	FairSchedulerConfiguration.parseResourceConfigValue(text, 0L);
	builder.minQueueResources(queueName, val.getResource());
	} else if (MAX_RESOURCES.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	ConfigurableResource val =
	FairSchedulerConfiguration.parseResourceConfigValue(text);
	builder.maxQueueResources(queueName, val);
	} else if (MAX_CHILD_RESOURCES.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	ConfigurableResource val =
	FairSchedulerConfiguration.parseResourceConfigValue(text);
	builder.maxChildQueueResources(queueName, val);
	} else if (MAX_RUNNING_APPS.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	int val = Integer.parseInt(text);
	builder.queueMaxApps(queueName, val);
	} else if (MAX_AMSHARE.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	float val = Float.parseFloat(text);
	val = Math.min(val, 1.0f);
	builder.queueMaxAMShares(queueName, val);
	isMaxAMShareSet = true;
	} else if (MAX_CONTAINER_ALLOCATION.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	ConfigurableResource val =
	FairSchedulerConfiguration.parseResourceConfigValue(text);
	builder.queueMaxContainerAllocation(queueName, val.getResource());
	} else if (WEIGHT.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	double val = Double.parseDouble(text);
	builder.queueWeights(queueName, (float) val);
	} else if (MIN_SHARE_PREEMPTION_TIMEOUT.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	long val = Long.parseLong(text) * 1000L;
	builder.minSharePreemptionTimeouts(queueName, val);
	} else if (FAIR_SHARE_PREEMPTION_TIMEOUT.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	long val = Long.parseLong(text) * 1000L;
	builder.fairSharePreemptionTimeouts(queueName, val);
	} else if (FAIR_SHARE_PREEMPTION_THRESHOLD.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	float val = Float.parseFloat(text);
	val = Math.max(Math.min(val, 1.0f), 0.0f);
	builder.fairSharePreemptionThresholds(queueName, val);
	} else if (SCHEDULING_POLICY.equals(field.getTagName())
	\|\| SCHEDULING_MODE.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	SchedulingPolicy policy = SchedulingPolicy.parse(text);
	builder.queuePolicies(queueName, policy);
	} else if (ACL_SUBMIT_APPS.equals(field.getTagName())) {
	String text = ((Text) field.getFirstChild()).getData();
	builder.queueAcls(queueName, AccessType.SUBMIT_APP,
	new AccessControlList(text));
	} else if (ACL_ADMINISTER_APPS.equals(field.getTagName())) {
	String text = ((Text) field.getFirstChild()).getData();
	builder.queueAcls(queueName, AccessType.ADMINISTER_QUEUE,
	new AccessControlList(text));
	} else if (ACL_ADMINISTER_RESERVATIONS.equals(field.getTagName())) {
	String text = ((Text) field.getFirstChild()).getData();
	builder.reservationAcls(queueName,
	ReservationACL.ADMINISTER_RESERVATIONS,
	new AccessControlList(text));
	} else if (ACL_LIST_RESERVATIONS.equals(field.getTagName())) {
	String text = ((Text) field.getFirstChild()).getData();
	builder.reservationAcls(queueName, ReservationACL.LIST_RESERVATIONS,
	new AccessControlList(text));
	} else if (ACL_SUBMIT_RESERVATIONS.equals(field.getTagName())) {
	String text = ((Text) field.getFirstChild()).getData();
	builder.reservationAcls(queueName, ReservationACL.SUBMIT_RESERVATIONS,
	new AccessControlList(text));
	} else if (RESERVATION.equals(field.getTagName())) {
	isReservable = true;
	builder.reservableQueues(queueName);
	builder.configuredQueues(FSQueueType.PARENT, queueName);
	} else if (ALLOW_PREEMPTION_FROM.equals(field.getTagName())) {
	String text = getTrimmedTextData(field);
	if (!Boolean.parseBoolean(text)) {
	builder.nonPreemptableQueues(queueName);
	}
	} else if (QUEUE.endsWith(field.getTagName())
	\|\| POOL.equals(field.getTagName())) {
	loadQueue(queueName, field, builder);
	isLeaf = false;
	}
	}
	// if a leaf in the alloc file is marked as type='parent'
	// then store it as a parent queue
	if (isLeaf && !"parent".equals(element.getAttribute("type"))) {
	// reservable queue has been already configured as parent
	if (!isReservable) {
	builder.configuredQueues(FSQueueType.LEAF, queueName);
	}
	} else {
	if (isReservable) {
	throw new AllocationConfigurationException(
	getErrorString(queueName, RESERVATION));
	} else if (isMaxAMShareSet) {
	throw new AllocationConfigurationException(
	getErrorString(queueName, MAX_AMSHARE));
	}
	builder.configuredQueues(FSQueueType.PARENT, queueName);
	}

	// Set default acls if not defined
	// The root queue defaults to all access
	for (QueueACL acl : QueueACL.values()) {
	AccessType accessType = SchedulerUtils.toAccessType(acl);
	if (!builder.isAclDefinedForAccessType(queueName, accessType)) {
	AccessControlList defaultAcl =
	queueName.equals(ROOT) ? EVERYBODY_ACL : NOBODY_ACL;
	builder.queueAcls(queueName, accessType, defaultAcl);
	}
	}

	checkMinAndMaxResource(builder.getMinQueueResources(),
	builder.getMaxQueueResources(), queueName);
	}

	/**
	* Set up the error string based on the supplied parent queueName and element.
	* @param parentQueueName the parent queue name.
	* @param element the element that should not be present for the parent queue.
	* @return the error string.
	*/
	private String getErrorString(String parentQueueName, String element) {
	return "The configuration settings"
	+ " for " + parentQueueName + " are invalid. A queue element that "
	+ "contains child queue elements or that has the type='parent' "
	+ "attribute cannot also include a " + element + " element.";
	}

	private String getTrimmedTextData(Element element) {
	return ((Text) element.getFirstChild()).getData().trim();
	}

	private void checkMinAndMaxResource(Map<String, Resource> minResources,
	Map<String, ConfigurableResource> maxResources, String queueName) {

	ConfigurableResource maxConfigurableResource = maxResources.get(queueName);
	Resource minResource = minResources.get(queueName);

	if (maxConfigurableResource != null && minResource != null) {
	Resource maxResource = maxConfigurableResource.getResource();

	// check whether max resource is greater or equals to min resource when
	// max resource are absolute values
	if (maxResource != null && !Resources.fitsIn(minResource, maxResource)) {
	LOG.warn(String.format(
	"Queue %s has max resources %s less than " + "min resources %s",
	queueName, maxResource, minResource));
	}
	}
	}
	}