opendaylight/hosttracker_new/implementation/src/main/java/org/opendaylight/controller/hosttracker/internal/Device.java

   1 /*
   2  * Copyright (c) 2011,2012 Big Switch Networks, Inc.
   3  *
   4  * Licensed under the Eclipse Public License, Version 1.0 (the
   5  * "License"); you may not use this file except in compliance with the
   6  * License. You may obtain a copy of the License at
   7  *
   8  *      http://www.eclipse.org/legal/epl-v10.html
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
  13  * implied. See the License for the specific language governing
  14  * permissions and limitations under the License.
  15  *
  16  * This file incorporates work covered by the following copyright and
  17  * permission notice:
  18  *
  19  *    Originally created by David Erickson, Stanford University
  20  *
  21  *    Licensed under the Apache License, Version 2.0 (the "License");
  22  *    you may not use this file except in compliance with the
  23  *    License. You may obtain a copy of the License at
  24  *
  25  *         http://www.apache.org/licenses/LICENSE-2.0
  26  *
  27  *    Unless required by applicable law or agreed to in writing,
  28  *    software distributed under the License is distributed on an "AS
  29  *    IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
  30  *    express or implied. See the License for the specific language
  31  *    governing permissions and limitations under the License.
  32  */
  33
  34 package org.opendaylight.controller.hosttracker.internal;
  35
  36 import java.net.InetAddress;
  37 import java.util.ArrayList;
  38 import java.util.Arrays;
  39 import java.util.Collection;
  40 import java.util.Collections;
  41 import java.util.Date;
  42 import java.util.EnumSet;
  43 import java.util.HashMap;
  44 import java.util.Iterator;
  45 import java.util.List;
  46 import java.util.Map;
  47 import java.util.TreeSet;
  48
  49 import org.opendaylight.controller.hosttracker.Entity;
  50 import org.opendaylight.controller.hosttracker.IDevice;
  51 import org.opendaylight.controller.hosttracker.IDeviceService.DeviceField;
  52 import org.opendaylight.controller.hosttracker.IEntityClass;
  53 import org.opendaylight.controller.hosttracker.SwitchPort;
  54 import org.opendaylight.controller.hosttracker.SwitchPort.ErrorStatus;
  55 import org.opendaylight.controller.hosttracker.hostAware.HostNodeConnector;
  56 import org.opendaylight.controller.sal.core.NodeConnector;
  57 import org.opendaylight.controller.sal.utils.HexEncode;
  58 import org.slf4j.Logger;
  59 import org.slf4j.LoggerFactory;
  60
  61 /**
  62  * Concrete implementation of {@link IDevice}
  63  *
  64  * @author readams
  65  */
  66 public class Device implements IDevice {
  67     protected static Logger log = LoggerFactory.getLogger(Device.class);
  68     public static final short VLAN_UNTAGGED = (short) 0xffff;
  69
  70     private final Long deviceKey;
  71     protected final DeviceManagerImpl deviceManager;
  72
  73     protected final Entity[] entities;
  74     private final IEntityClass entityClass;
  75
  76     protected final String macAddressString;
  77     // the vlan Ids from the entities of this device
  78     protected final Short[] vlanIds;
  79     protected volatile String dhcpClientName;
  80
  81     private boolean staticHost;
  82
  83     /**
  84      * These are the old attachment points for the device that were valid no
  85      * more than INACTIVITY_TIME ago.
  86      */
  87     protected volatile List<AttachmentPoint> oldAPs;
  88     /**
  89      * The current attachment points for the device.
  90      */
  91     protected volatile List<AttachmentPoint> attachmentPoints;
  92
  93     // ************
  94     // Constructors
  95     // ************
  96
  97     /**
  98      * Create a device from an entities
  99      *
 100      * @param deviceManager
 101      *            the device manager for this device
 102      * @param deviceKey
 103      *            the unique identifier for this device object
 104      * @param entity
 105      *            the initial entity for the device
 106      * @param entityClass
 107      *            the entity classes associated with the entity
 108      */
 109     public Device(DeviceManagerImpl deviceManager, Long deviceKey,
 110             Entity entity, IEntityClass entityClass) {
 111         this.deviceManager = deviceManager;
 112         this.deviceKey = deviceKey;
 113         this.entities = new Entity[] { entity };
 114         this.macAddressString = HexEncode.longToHexString(entity
 115                 .getMacAddress());
 116         this.entityClass = entityClass;
 117         Arrays.sort(this.entities);
 118
 119         this.dhcpClientName = null;
 120         this.oldAPs = null;
 121         this.attachmentPoints = null;
 122
 123         if (entity.getPort() != null) {
 124             NodeConnector port = entity.getPort();
 125
 126             if (deviceManager.isValidAttachmentPoint(port)) {
 127                 AttachmentPoint ap;
 128                 ap = new AttachmentPoint(port, entity.getLastSeenTimestamp()
 129                         .getTime());
 130
 131                 this.attachmentPoints = new ArrayList<AttachmentPoint>();
 132                 this.attachmentPoints.add(ap);
 133             }
 134         }
 135         vlanIds = computeVlandIds();
 136     }
 137
 138     /**
 139      * Create a device from a set of entities
 140      *
 141      * @param deviceManager
 142      *            the device manager for this device
 143      * @param deviceKey
 144      *            the unique identifier for this device object
 145      * @param entities
 146      *            the initial entities for the device
 147      * @param entityClass
 148      *            the entity class associated with the entities
 149      */
 150     public Device(DeviceManagerImpl deviceManager, Long deviceKey,
 151             String dhcpClientName, Collection<AttachmentPoint> oldAPs,
 152             Collection<AttachmentPoint> attachmentPoints,
 153             Collection<Entity> entities, IEntityClass entityClass) {
 154         this.deviceManager = deviceManager;
 155         this.deviceKey = deviceKey;
 156         this.dhcpClientName = dhcpClientName;
 157         this.entities = entities.toArray(new Entity[entities.size()]);
 158         this.oldAPs = null;
 159         this.attachmentPoints = null;
 160         if (oldAPs != null) {
 161             this.oldAPs = new ArrayList<AttachmentPoint>(oldAPs);
 162         }
 163         if (attachmentPoints != null) {
 164             this.attachmentPoints = new ArrayList<AttachmentPoint>(
 165                     attachmentPoints);
 166         }
 167         this.macAddressString = HexEncode.longToHexString(this.entities[0]
 168                 .getMacAddress());
 169         this.entityClass = entityClass;
 170         Arrays.sort(this.entities);
 171         vlanIds = computeVlandIds();
 172     }
 173
 174     /**
 175      * Construct a new device consisting of the entities from the old device
 176      * plus an additional entity. The caller needs to ensure that the additional
 177      * entity is not already present in the array
 178      *
 179      * @param device
 180      *            the old device object
 181      * @param newEntity
 182      *            the entity to add. newEntity must be have the same entity
 183      *            class as device
 184      * @param if positive indicates the index in the entities array were the new
 185      *        entity should be inserted. If negative we will compute the correct
 186      *        insertion point
 187      */
 188     public Device(Device device, Entity newEntity, int insertionpoint) {
 189         this.deviceManager = device.deviceManager;
 190         this.deviceKey = device.deviceKey;
 191         this.dhcpClientName = device.dhcpClientName;
 192
 193         this.entities = new Entity[device.entities.length + 1];
 194         if (insertionpoint < 0) {
 195             insertionpoint = -(Arrays.binarySearch(device.entities, newEntity) + 1);
 196         }
 197         if (insertionpoint > 0) {
 198             // insertion point is not the beginning:
 199             // copy up to insertion point
 200             System.arraycopy(device.entities, 0, this.entities, 0,
 201                     insertionpoint);
 202         }
 203         if (insertionpoint < device.entities.length) {
 204             // insertion point is not the end
 205             // copy from insertion point
 206             System.arraycopy(device.entities, insertionpoint, this.entities,
 207                     insertionpoint + 1, device.entities.length - insertionpoint);
 208         }
 209         this.entities[insertionpoint] = newEntity;
 210         /*
 211          * this.entities = Arrays.<Entity>copyOf(device.entities,
 212          * device.entities.length + 1); this.entities[this.entities.length - 1]
 213          * = newEntity; Arrays.sort(this.entities);
 214          */
 215         this.oldAPs = null;
 216         if (device.oldAPs != null) {
 217             this.oldAPs = new ArrayList<AttachmentPoint>(device.oldAPs);
 218         }
 219         this.attachmentPoints = null;
 220         if (device.attachmentPoints != null) {
 221             this.attachmentPoints = new ArrayList<AttachmentPoint>(
 222                     device.attachmentPoints);
 223         }
 224
 225         this.macAddressString = HexEncode.longToHexString(this.entities[0]
 226                 .getMacAddress());
 227
 228         this.entityClass = device.entityClass;
 229         vlanIds = computeVlandIds();
 230     }
 231
 232     private Short[] computeVlandIds() {
 233         if (entities.length == 1) {
 234             if (entities[0].getVlan() != null) {
 235                 return new Short[] { entities[0].getVlan() };
 236             } else {
 237                 return new Short[] { Short.valueOf((short) -1) };
 238             }
 239         }
 240
 241         TreeSet<Short> vals = new TreeSet<Short>();
 242         for (Entity e : entities) {
 243             if (e.getVlan() == null)
 244                 vals.add((short) -1);
 245             else
 246                 vals.add(e.getVlan());
 247         }
 248         return vals.toArray(new Short[vals.size()]);
 249     }
 250
 251     /**
 252      * Given a list of attachment points (apList), the procedure would return a
 253      * map of attachment points for each L2 domain. L2 domain id is the key.
 254      *
 255      * @param apList
 256      * @return
 257      */
 258     private Map<Long, AttachmentPoint> getAPMap(List<AttachmentPoint> apList) {
 259
 260         if (apList == null)
 261             return null;
 262         // ITopologyService topology = deviceManager.topology;
 263
 264         // Get the old attachment points and sort them.
 265         List<AttachmentPoint> oldAP = new ArrayList<AttachmentPoint>();
 266         if (apList != null)
 267             oldAP.addAll(apList);
 268
 269         // Remove invalid attachment points before sorting.
 270         List<AttachmentPoint> tempAP = new ArrayList<AttachmentPoint>();
 271         for (AttachmentPoint ap : oldAP) {
 272             if (deviceManager.isValidAttachmentPoint(ap.getPort())) {
 273                 tempAP.add(ap);
 274             }
 275         }
 276         oldAP = tempAP;
 277
 278         Collections.sort(oldAP, deviceManager.apComparator);
 279
 280         // Map of attachment point by L2 domain Id.
 281         Map<Long, AttachmentPoint> apMap = new HashMap<Long, AttachmentPoint>();
 282
 283         for (int i = 0; i < oldAP.size(); ++i) {
 284             AttachmentPoint ap = oldAP.get(i);
 285             // if this is not a valid attachment point, continue
 286             if (!deviceManager.isValidAttachmentPoint(ap.getPort()))
 287                 continue;
 288
 289             // long id = topology.getL2DomainId(ap.getSw());
 290             // XXX - Missing functionality
 291             long id = 0;
 292
 293             apMap.put(id, ap);
 294         }
 295
 296         if (apMap.isEmpty())
 297             return null;
 298         return apMap;
 299     }
 300
 301     /**
 302      * Remove all attachment points that are older than INACTIVITY_INTERVAL from
 303      * the list.
 304      *
 305      * @param apList
 306      * @return
 307      */
 308     private boolean removeExpiredAttachmentPoints(List<AttachmentPoint> apList) {
 309
 310         List<AttachmentPoint> expiredAPs = new ArrayList<AttachmentPoint>();
 311
 312         if (apList == null)
 313             return false;
 314
 315         for (AttachmentPoint ap : apList) {
 316             if (ap.getLastSeen() + AttachmentPoint.INACTIVITY_INTERVAL < System
 317                     .currentTimeMillis())
 318                 expiredAPs.add(ap);
 319         }
 320         if (expiredAPs.size() > 0) {
 321             apList.removeAll(expiredAPs);
 322             return true;
 323         } else
 324             return false;
 325     }
 326
 327     /**
 328      * Get a list of duplicate attachment points, given a list of old attachment
 329      * points and one attachment point per L2 domain. Given a true attachment
 330      * point in the L2 domain, say trueAP, another attachment point in the same
 331      * L2 domain, say ap, is duplicate if: 1. ap is inconsistent with trueAP,
 332      * and 2. active time of ap is after that of trueAP; and 3. last seen time
 333      * of ap is within the last INACTIVITY_INTERVAL
 334      *
 335      * @param oldAPList
 336      * @param apMap
 337      * @return
 338      */
 339     List<AttachmentPoint> getDuplicateAttachmentPoints(
 340             List<AttachmentPoint> oldAPList, Map<Long, AttachmentPoint> apMap) {
 341         // ITopologyService topology = deviceManager.topology;
 342         List<AttachmentPoint> dupAPs = new ArrayList<AttachmentPoint>();
 343         long timeThreshold = System.currentTimeMillis()
 344                 - AttachmentPoint.INACTIVITY_INTERVAL;
 345
 346         if (oldAPList == null || apMap == null)
 347             return dupAPs;
 348
 349         for (AttachmentPoint ap : oldAPList) {
 350             // XXX - Missing functionality
 351             // long id = topology.getL2DomainId(ap.getSw());
 352             long id = 0;
 353             AttachmentPoint trueAP = apMap.get(id);
 354
 355             if (trueAP == null)
 356                 continue;
 357             // XXX - Missing functionality
 358             // boolean c = (topology.isConsistent(trueAP.getSw(),
 359             // trueAP.getPort(),
 360             // ap.getSw(), ap.getPort()));
 361             boolean c = true;
 362             boolean active = (ap.getActiveSince() > trueAP.getActiveSince());
 363             boolean last = ap.getLastSeen() > timeThreshold;
 364             if (!c && active && last) {
 365                 dupAPs.add(ap);
 366             }
 367         }
 368
 369         return dupAPs;
 370     }
 371
 372     /**
 373      * Update the known attachment points. This method is called whenever
 374      * topology changes. The method returns true if there's any change to the
 375      * list of attachment points -- which indicates a possible device move.
 376      *
 377      * @return
 378      */
 379     protected boolean updateAttachmentPoint() {
 380         boolean moved = false;
 381         this.oldAPs = attachmentPoints;
 382         if (attachmentPoints == null || attachmentPoints.isEmpty())
 383             return false;
 384
 385         List<AttachmentPoint> apList = new ArrayList<AttachmentPoint>();
 386         if (attachmentPoints != null)
 387             apList.addAll(attachmentPoints);
 388         Map<Long, AttachmentPoint> newMap = getAPMap(apList);
 389         if (newMap == null || newMap.size() != apList.size()) {
 390             moved = true;
 391         }
 392
 393         // Prepare the new attachment point list.
 394         if (moved) {
 395             log.info("updateAttachmentPoint: ap {}  newmap {} ",
 396                     attachmentPoints, newMap);
 397             List<AttachmentPoint> newAPList = new ArrayList<AttachmentPoint>();
 398             if (newMap != null)
 399                 newAPList.addAll(newMap.values());
 400             this.attachmentPoints = newAPList;
 401         }
 402
 403         // Set the oldAPs to null.
 404         return moved;
 405     }
 406
 407     /**
 408      * Update the list of attachment points given that a new packet-in was seen
 409      * from (sw, port) at time (lastSeen). The return value is true if there was
 410      * any change to the list of attachment points for the device -- which
 411      * indicates a device move.
 412      *
 413      * @param sw
 414      * @param port
 415      * @param lastSeen
 416      * @return
 417      */
 418     protected boolean updateAttachmentPoint(NodeConnector port, long lastSeen) {
 419         // ITopologyService topology = deviceManager.topology;
 420         List<AttachmentPoint> oldAPList;
 421         List<AttachmentPoint> apList;
 422         boolean oldAPFlag = false;
 423
 424         if (!deviceManager.isValidAttachmentPoint(port))
 425             return false;
 426         AttachmentPoint newAP = new AttachmentPoint(port, lastSeen);
 427         // Copy the oldAP and ap list.
 428         apList = new ArrayList<AttachmentPoint>();
 429         if (attachmentPoints != null)
 430             apList.addAll(attachmentPoints);
 431         oldAPList = new ArrayList<AttachmentPoint>();
 432         if (oldAPs != null)
 433             oldAPList.addAll(oldAPs);
 434
 435         // if the sw, port is in old AP, remove it from there
 436         // and update the lastSeen in that object.
 437         if (oldAPList.contains(newAP)) {
 438             int index = oldAPList.indexOf(newAP);
 439             newAP = oldAPList.remove(index);
 440             newAP.setLastSeen(lastSeen);
 441             this.oldAPs = oldAPList;
 442             oldAPFlag = true;
 443         }
 444
 445         // newAP now contains the new attachment point.
 446
 447         // Get the APMap is null or empty.
 448         Map<Long, AttachmentPoint> apMap = getAPMap(apList);
 449         if (apMap == null || apMap.isEmpty()) {
 450             apList.add(newAP);
 451             attachmentPoints = apList;
 452             // there are no old attachment points - since the device exists,
 453             // this
 454             // may be because the host really moved (so the old AP port went
 455             // down);
 456             // or it may be because the switch restarted (so old APs were
 457             // nullified).
 458             // For now we will treat both cases as host moved.
 459             return true;
 460         }
 461
 462         // XXX - Missing functionality
 463         // long id = topology.getL2DomainId(sw);
 464         long id = 0;
 465         AttachmentPoint oldAP = apMap.get(id);
 466
 467         if (oldAP == null) // No attachment on this L2 domain.
 468         {
 469             apList = new ArrayList<AttachmentPoint>();
 470             apList.addAll(apMap.values());
 471             apList.add(newAP);
 472             this.attachmentPoints = apList;
 473             return true; // new AP found on an L2 island.
 474         }
 475
 476         // There is already a known attachment point on the same L2 island.
 477         // we need to compare oldAP and newAP.
 478         if (oldAP.equals(newAP)) {
 479             // nothing to do here. just the last seen has to be changed.
 480             if (newAP.lastSeen > oldAP.lastSeen) {
 481                 oldAP.setLastSeen(newAP.lastSeen);
 482             }
 483             this.attachmentPoints = new ArrayList<AttachmentPoint>(
 484                     apMap.values());
 485             return false; // nothing to do here.
 486         }
 487
 488         int x = deviceManager.apComparator.compare(oldAP, newAP);
 489         if (x < 0) {
 490             // newAP replaces oldAP.
 491             apMap.put(id, newAP);
 492             this.attachmentPoints = new ArrayList<AttachmentPoint>(
 493                     apMap.values());
 494
 495             oldAPList = new ArrayList<AttachmentPoint>();
 496             if (oldAPs != null)
 497                 oldAPList.addAll(oldAPs);
 498             oldAPList.add(oldAP);
 499             this.oldAPs = oldAPList;
 500             // XXX - Missing functionality
 501             // if (!topology.isInSameBroadcastDomain(oldAP.getSw(),
 502             // oldAP.getPort(),
 503             // newAP.getSw(), newAP.getPort()))
 504             // return true; // attachment point changed.
 505             return true;
 506         } else if (oldAPFlag) {
 507             // retain oldAP as is. Put the newAP in oldAPs for flagging
 508             // possible duplicates.
 509             oldAPList = new ArrayList<AttachmentPoint>();
 510             if (oldAPs != null)
 511                 oldAPList.addAll(oldAPs);
 512             // Add to oldAPList only if it was picked up from the oldAPList
 513             oldAPList.add(newAP);
 514             this.oldAPs = oldAPList;
 515             // XXX - Missing functionality
 516             // if (!topology.isInSameBroadcastDomain(oldAP.getSw(),
 517             // oldAP.getPort(),
 518             // newAP.getSw(), newAP.getPort()))
 519             // return true; // attachment point changed.
 520             return true;
 521         }
 522         return false;
 523     }
 524
 525     /**
 526      * Delete (sw,port) from the list of list of attachment points and oldAPs.
 527      *
 528      * @param sw
 529      * @param port
 530      * @return
 531      */
 532     public boolean deleteAttachmentPoint(NodeConnector port) {
 533         AttachmentPoint ap = new AttachmentPoint(port, 0);
 534
 535         if (this.oldAPs != null) {
 536             ArrayList<AttachmentPoint> apList = new ArrayList<AttachmentPoint>();
 537             apList.addAll(this.oldAPs);
 538             int index = apList.indexOf(ap);
 539             if (index > 0) {
 540                 apList.remove(index);
 541                 this.oldAPs = apList;
 542             }
 543         }
 544
 545         if (this.attachmentPoints != null) {
 546             ArrayList<AttachmentPoint> apList = new ArrayList<AttachmentPoint>();
 547             apList.addAll(this.attachmentPoints);
 548             int index = apList.indexOf(ap);
 549             if (index > 0) {
 550                 apList.remove(index);
 551                 this.attachmentPoints = apList;
 552                 return true;
 553             }
 554         }
 555         return false;
 556     }
 557
 558     // *******
 559     // IDevice
 560     // *******
 561
 562     @Override
 563     public SwitchPort[] getOldAP() {
 564         List<SwitchPort> sp = new ArrayList<SwitchPort>();
 565         SwitchPort[] returnSwitchPorts = new SwitchPort[] {};
 566         if (oldAPs == null)
 567             return returnSwitchPorts;
 568         if (oldAPs.isEmpty())
 569             return returnSwitchPorts;
 570
 571         // copy ap list.
 572         List<AttachmentPoint> oldAPList;
 573         oldAPList = new ArrayList<AttachmentPoint>();
 574
 575         if (oldAPs != null)
 576             oldAPList.addAll(oldAPs);
 577         removeExpiredAttachmentPoints(oldAPList);
 578
 579         if (oldAPList != null) {
 580             for (AttachmentPoint ap : oldAPList) {
 581                 SwitchPort swport = new SwitchPort(ap.getPort());
 582                 sp.add(swport);
 583             }
 584         }
 585         return sp.toArray(new SwitchPort[sp.size()]);
 586     }
 587
 588     @Override
 589     public SwitchPort[] getAttachmentPoints() {
 590         return getAttachmentPoints(false);
 591     }
 592
 593     @Override
 594     public SwitchPort[] getAttachmentPoints(boolean includeError) {
 595         List<SwitchPort> sp = new ArrayList<SwitchPort>();
 596         SwitchPort[] returnSwitchPorts = new SwitchPort[] {};
 597         if (attachmentPoints == null)
 598             return returnSwitchPorts;
 599         if (attachmentPoints.isEmpty())
 600             return returnSwitchPorts;
 601
 602         // copy ap list.
 603         List<AttachmentPoint> apList = attachmentPoints;
 604
 605         if (apList != null) {
 606             for (AttachmentPoint ap : apList) {
 607                 SwitchPort swport = new SwitchPort(ap.getPort());
 608                 sp.add(swport);
 609             }
 610         }
 611
 612         if (!includeError)
 613             return sp.toArray(new SwitchPort[sp.size()]);
 614
 615         List<AttachmentPoint> oldAPList;
 616         oldAPList = new ArrayList<AttachmentPoint>();
 617
 618         if (oldAPs != null)
 619             oldAPList.addAll(oldAPs);
 620
 621         if (removeExpiredAttachmentPoints(oldAPList))
 622             this.oldAPs = oldAPList;
 623
 624         List<AttachmentPoint> dupList;
 625         // get AP map.
 626         Map<Long, AttachmentPoint> apMap = getAPMap(apList);
 627         dupList = this.getDuplicateAttachmentPoints(oldAPList, apMap);
 628         if (dupList != null) {
 629             for (AttachmentPoint ap : dupList) {
 630                 SwitchPort swport = new SwitchPort(ap.getPort(),
 631                         ErrorStatus.DUPLICATE_DEVICE);
 632                 sp.add(swport);
 633             }
 634         }
 635         return sp.toArray(new SwitchPort[sp.size()]);
 636     }
 637
 638     @Override
 639     public Long getDeviceKey() {
 640         return deviceKey;
 641     }
 642
 643     @Override
 644     public long getMACAddress() {
 645         // we assume only one MAC per device for now.
 646         return entities[0].getMacAddress();
 647     }
 648
 649     @Override
 650     public String getMACAddressString() {
 651         return macAddressString;
 652     }
 653
 654     @Override
 655     public Short[] getVlanId() {
 656         return Arrays.copyOf(vlanIds, vlanIds.length);
 657     }
 658
 659     static final EnumSet<DeviceField> ipv4Fields = EnumSet.of(DeviceField.IPV4);
 660
 661     @Override
 662     public Integer[] getIPv4Addresses() {
 663         // XXX - TODO we can cache this result. Let's find out if this
 664         // is really a performance bottleneck first though.
 665
 666         TreeSet<Integer> vals = new TreeSet<Integer>();
 667         for (Entity e : entities) {
 668             if (e.getIpv4Address() == null)
 669                 continue;
 670
 671             // We have an IP address only if among the devices within the class
 672             // we have the most recent entity with that IP.
 673             boolean validIP = true;
 674             Iterator<Device> devices = deviceManager.queryClassByEntity(
 675                     entityClass, ipv4Fields, e);
 676             while (devices.hasNext()) {
 677                 Device d = devices.next();
 678                 if (deviceKey.equals(d.getDeviceKey()))
 679                     continue;
 680                 for (Entity se : d.entities) {
 681                     if (se.getIpv4Address() != null
 682                             && se.getIpv4Address().equals(e.getIpv4Address())
 683                             && se.getLastSeenTimestamp() != null
 684                             && 0 < se.getLastSeenTimestamp().compareTo(
 685                                     e.getLastSeenTimestamp())) {
 686                         validIP = false;
 687                         break;
 688                     }
 689                 }
 690                 if (!validIP)
 691                     break;
 692             }
 693
 694             if (validIP)
 695                 vals.add(e.getIpv4Address());
 696         }
 697
 698         return vals.toArray(new Integer[vals.size()]);
 699     }
 700
 701     @Override
 702     public Short[] getSwitchPortVlanIds(SwitchPort swp) {
 703         TreeSet<Short> vals = new TreeSet<Short>();
 704         for (Entity e : entities) {
 705             if (e.getPort().equals(swp.getPort())) {
 706                 if (e.getVlan() == null)
 707                     vals.add(VLAN_UNTAGGED);
 708                 else
 709                     vals.add(e.getVlan());
 710             }
 711         }
 712         return vals.toArray(new Short[vals.size()]);
 713     }
 714
 715     @Override
 716     public Date getLastSeen() {
 717         Date d = null;
 718         for (int i = 0; i < entities.length; i++) {
 719             if (d == null
 720                     || entities[i].getLastSeenTimestamp().compareTo(d) > 0)
 721                 d = entities[i].getLastSeenTimestamp();
 722         }
 723         return d;
 724     }
 725
 726     // ***************
 727     // Getters/Setters
 728     // ***************
 729
 730     @Override
 731     public IEntityClass getEntityClass() {
 732         return entityClass;
 733     }
 734
 735     public Entity[] getEntities() {
 736         return entities;
 737     }
 738
 739     public String getDHCPClientName() {
 740         return dhcpClientName;
 741     }
 742
 743     // ***************
 744     // Utility Methods
 745     // ***************
 746
 747     /**
 748      * Check whether the device contains the specified entity
 749      *
 750      * @param entity
 751      *            the entity to search for
 752      * @return the index of the entity, or <0 if not found
 753      */
 754     protected int entityIndex(Entity entity) {
 755         return Arrays.binarySearch(entities, entity);
 756     }
 757
 758     // ******
 759     // Object
 760     // ******
 761
 762     @Override
 763     public int hashCode() {
 764         final int prime = 31;
 765         int result = 1;
 766         result = prime * result + Arrays.hashCode(entities);
 767         return result;
 768     }
 769
 770     @Override
 771     public boolean equals(Object obj) {
 772         if (this == obj)
 773             return true;
 774         if (obj == null)
 775             return false;
 776         if (getClass() != obj.getClass())
 777             return false;
 778         Device other = (Device) obj;
 779         if (!deviceKey.equals(other.deviceKey))
 780             return false;
 781         if (!Arrays.equals(entities, other.entities))
 782             return false;
 783         return true;
 784     }
 785
 786     public HostNodeConnector toHostNodeConnector() {
 787         Integer[] ipv4s = this.getIPv4Addresses();
 788         try {
 789             Entity e = this.entities[this.entities.length-1];
 790             NodeConnector n = null;
 791             if(e!=null)
 792                  n = e.getPort();
 793             InetAddress ip = InetAddress.getByName(ipv4s[ipv4s.length - 1]
 794                     .toString());
 795             byte[] macAddr = macLongToByte(this.getMACAddress());
 796             HostNodeConnector nc = new HostNodeConnector(macAddr, ip, n,
 797                     (short) 0);
 798             nc.setStaticHost(this.isStaticHost());
 799             return nc;
 800         } catch (Exception e) {
 801             return null;
 802         }
 803     }
 804
 805     private byte[] macLongToByte(long mac) {
 806         byte[] macAddr = new byte[6];
 807         for (int i = 0; i < 6; i++) {
 808             macAddr[5 - i] = (byte) (mac >> (8 * i));
 809         }
 810         return macAddr;
 811     }
 812
 813     public boolean isStaticHost(){
 814         return this.staticHost;
 815     }
 816
 817     public void setStaticHost(boolean isStatic){
 818         this.staticHost = isStatic;
 819     }
 820
 821     @Override
 822     public String toString() {
 823         StringBuilder builder = new StringBuilder();
 824         builder.append("Device [deviceKey=");
 825         builder.append(deviceKey);
 826         builder.append(", entityClass=");
 827         builder.append(entityClass.getName());
 828         builder.append(", MAC=");
 829         builder.append(macAddressString);
 830         builder.append(", IPs=[");
 831         boolean isFirst = true;
 832         for (Integer ip : getIPv4Addresses()) {
 833             if (!isFirst)
 834                 builder.append(", ");
 835             isFirst = false;
 836             // builder.append(IPv4.fromIPv4Address(ip));
 837             builder.append(ip);
 838         }
 839         builder.append("], APs=");
 840         builder.append(Arrays.toString(getAttachmentPoints(true)));
 841         builder.append("]");
 842         return builder.toString();
 843     }
 844 }