git.basschouten.com Git - openhab-addons.git/blob

   1 /**
   2  * Copyright (c) 2010-2020 Contributors to the openHAB project
   3  *
   4  * See the NOTICE file(s) distributed with this work for additional
   5  * information.
   6  *
   7  * This program and the accompanying materials are made available under the
   8  * terms of the Eclipse Public License 2.0 which is available at
   9  * http://www.eclipse.org/legal/epl-2.0
  10  *
  11  * SPDX-License-Identifier: EPL-2.0
  12  */
  13 package org.openhab.binding.modbus.internal.handler;
  14
  15 import static org.openhab.binding.modbus.internal.ModbusBindingConstantsInternal.*;
  16
  17 import java.math.BigDecimal;
  18 import java.time.Duration;
  19 import java.time.LocalDateTime;
  20 import java.util.*;
  21 import java.util.concurrent.TimeUnit;
  22
  23 import org.apache.commons.lang.NotImplementedException;
  24 import org.apache.commons.lang.StringUtils;
  25 import org.eclipse.jdt.annotation.NonNullByDefault;
  26 import org.eclipse.jdt.annotation.Nullable;
  27 import org.openhab.binding.modbus.handler.EndpointNotInitializedException;
  28 import org.openhab.binding.modbus.handler.ModbusEndpointThingHandler;
  29 import org.openhab.binding.modbus.handler.ModbusPollerThingHandler;
  30 import org.openhab.binding.modbus.internal.ModbusBindingConstantsInternal;
  31 import org.openhab.binding.modbus.internal.ModbusConfigurationException;
  32 import org.openhab.binding.modbus.internal.Transformation;
  33 import org.openhab.binding.modbus.internal.config.ModbusDataConfiguration;
  34 import org.openhab.core.library.items.ContactItem;
  35 import org.openhab.core.library.items.DateTimeItem;
  36 import org.openhab.core.library.items.DimmerItem;
  37 import org.openhab.core.library.items.NumberItem;
  38 import org.openhab.core.library.items.RollershutterItem;
  39 import org.openhab.core.library.items.StringItem;
  40 import org.openhab.core.library.items.SwitchItem;
  41 import org.openhab.core.library.types.DateTimeType;
  42 import org.openhab.core.library.types.DecimalType;
  43 import org.openhab.core.library.types.OnOffType;
  44 import org.openhab.core.library.types.OpenClosedType;
  45 import org.openhab.core.thing.Bridge;
  46 import org.openhab.core.thing.ChannelUID;
  47 import org.openhab.core.thing.Thing;
  48 import org.openhab.core.thing.ThingStatus;
  49 import org.openhab.core.thing.ThingStatusDetail;
  50 import org.openhab.core.thing.ThingStatusInfo;
  51 import org.openhab.core.thing.binding.BaseThingHandler;
  52 import org.openhab.core.thing.binding.BridgeHandler;
  53 import org.openhab.core.thing.binding.ThingHandlerCallback;
  54 import org.openhab.core.types.Command;
  55 import org.openhab.core.types.RefreshType;
  56 import org.openhab.core.types.State;
  57 import org.openhab.core.types.UnDefType;
  58 import org.openhab.io.transport.modbus.AsyncModbusFailure;
  59 import org.openhab.io.transport.modbus.AsyncModbusReadResult;
  60 import org.openhab.io.transport.modbus.AsyncModbusWriteResult;
  61 import org.openhab.io.transport.modbus.BitArray;
  62 import org.openhab.io.transport.modbus.ModbusBitUtilities;
  63 import org.openhab.io.transport.modbus.ModbusCommunicationInterface;
  64 import org.openhab.io.transport.modbus.ModbusConstants;
  65 import org.openhab.io.transport.modbus.ModbusConstants.ValueType;
  66 import org.openhab.io.transport.modbus.ModbusReadFunctionCode;
  67 import org.openhab.io.transport.modbus.ModbusReadRequestBlueprint;
  68 import org.openhab.io.transport.modbus.ModbusRegisterArray;
  69 import org.openhab.io.transport.modbus.ModbusWriteCoilRequestBlueprint;
  70 import org.openhab.io.transport.modbus.ModbusWriteRegisterRequestBlueprint;
  71 import org.openhab.io.transport.modbus.ModbusWriteRequestBlueprint;
  72 import org.openhab.io.transport.modbus.exception.ModbusConnectionException;
  73 import org.openhab.io.transport.modbus.exception.ModbusTransportException;
  74 import org.openhab.io.transport.modbus.json.WriteRequestJsonUtilities;
  75 import org.osgi.framework.BundleContext;
  76 import org.osgi.framework.FrameworkUtil;
  77 import org.slf4j.Logger;
  78 import org.slf4j.LoggerFactory;
  79
  80 /**
  81  * The {@link ModbusDataThingHandler} is responsible for interpreting polled modbus data, as well as handling openHAB
  82  * commands
  83  *
  84  * Thing can be re-initialized by the bridge in case of configuration changes (bridgeStatusChanged).
  85  * Because of this, initialize, dispose and all callback methods (onRegisters, onBits, onError, onWriteResponse) are
  86  * synchronized
  87  * to avoid data race conditions.
  88  *
  89  * @author Sami Salonen - Initial contribution
  90  */
  91 @NonNullByDefault
  92 public class ModbusDataThingHandler extends BaseThingHandler {
  93
  94     private final Logger logger = LoggerFactory.getLogger(ModbusDataThingHandler.class);
  95
  96     private final BundleContext bundleContext;
  97
  98     private static final Duration MIN_STATUS_INFO_UPDATE_INTERVAL = Duration.ofSeconds(1);
  99     private static final Map<String, List<Class<? extends State>>> CHANNEL_ID_TO_ACCEPTED_TYPES = new HashMap<>();
 100
 101     static {
 102         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_SWITCH,
 103                 new SwitchItem("").getAcceptedDataTypes());
 104         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_CONTACT,
 105                 new ContactItem("").getAcceptedDataTypes());
 106         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_DATETIME,
 107                 new DateTimeItem("").getAcceptedDataTypes());
 108         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_DIMMER,
 109                 new DimmerItem("").getAcceptedDataTypes());
 110         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_NUMBER,
 111                 new NumberItem("").getAcceptedDataTypes());
 112         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_STRING,
 113                 new StringItem("").getAcceptedDataTypes());
 114         CHANNEL_ID_TO_ACCEPTED_TYPES.put(ModbusBindingConstantsInternal.CHANNEL_ROLLERSHUTTER,
 115                 new RollershutterItem("").getAcceptedDataTypes());
 116     }
 117     // data channels + 4 for read/write last error/success
 118     private static final int NUMER_OF_CHANNELS_HINT = CHANNEL_ID_TO_ACCEPTED_TYPES.size() + 4;
 119
 120     //
 121     // If you change the below default/initial values, please update the corresponding values in dispose()
 122     //
 123     private volatile @Nullable ModbusDataConfiguration config;
 124     private volatile @Nullable ValueType readValueType;
 125     private volatile @Nullable ValueType writeValueType;
 126     private volatile @Nullable Transformation readTransformation;
 127     private volatile @Nullable Transformation writeTransformation;
 128     private volatile Optional<Integer> readIndex = Optional.empty();
 129     private volatile Optional<Integer> readSubIndex = Optional.empty();
 130     private volatile @Nullable Integer writeStart;
 131     private volatile int pollStart;
 132     private volatile int slaveId;
 133     private volatile @Nullable ModbusReadFunctionCode functionCode;
 134     private volatile @Nullable ModbusReadRequestBlueprint readRequest;
 135     private volatile long updateUnchangedValuesEveryMillis;
 136     private volatile @NonNullByDefault({}) ModbusCommunicationInterface comms;
 137     private volatile boolean isWriteEnabled;
 138     private volatile boolean isReadEnabled;
 139     private volatile boolean writeParametersHavingTransformationOnly;
 140     private volatile boolean childOfEndpoint;
 141     private volatile @Nullable ModbusPollerThingHandler pollerHandler;
 142     private volatile Map<String, ChannelUID> channelCache = new HashMap<>();
 143     private volatile Map<ChannelUID, Long> channelLastUpdated = new HashMap<>(NUMER_OF_CHANNELS_HINT);
 144     private volatile Map<ChannelUID, State> channelLastState = new HashMap<>(NUMER_OF_CHANNELS_HINT);
 145
 146     private volatile LocalDateTime lastStatusInfoUpdate = LocalDateTime.MIN;
 147     private volatile ThingStatusInfo statusInfo = new ThingStatusInfo(ThingStatus.UNKNOWN, ThingStatusDetail.NONE,
 148             null);
 149
 150     public ModbusDataThingHandler(Thing thing) {
 151         super(thing);
 152         this.bundleContext = FrameworkUtil.getBundle(ModbusDataThingHandler.class).getBundleContext();
 153     }
 154
 155     @Override
 156     public synchronized void handleCommand(ChannelUID channelUID, Command command) {
 157         logger.trace("Thing {} '{}' received command '{}' to channel '{}'", getThing().getUID(), getThing().getLabel(),
 158                 command, channelUID);
 159         ModbusDataConfiguration config = this.config;
 160         if (config == null) {
 161             return;
 162         }
 163
 164         if (RefreshType.REFRESH == command) {
 165             ModbusPollerThingHandler poller = pollerHandler;
 166             if (poller == null) {
 167                 // Data thing must be child of endpoint, and thus write-only.
 168                 // There is no data to update
 169                 return;
 170             }
 171             // We *schedule* the REFRESH to avoid dead-lock situation where poller is trying update this
 172             // data thing with cached data (resulting in deadlock in two synchronized methods: this (handleCommand) and
 173             // onRegisters.
 174             scheduler.schedule(() -> poller.refresh(), 0, TimeUnit.SECONDS);
 175             return;
 176         } else if (hasConfigurationError()) {
 177             logger.debug(
 178                     "Thing {} '{}' command '{}' to channel '{}': Thing has configuration error so ignoring the command",
 179                     getThing().getUID(), getThing().getLabel(), command, channelUID);
 180             return;
 181         } else if (!isWriteEnabled) {
 182             logger.debug(
 183                     "Thing {} '{}' command '{}' to channel '{}': no writing configured -> aborting processing command",
 184                     getThing().getUID(), getThing().getLabel(), command, channelUID);
 185             return;
 186         }
 187
 188         Optional<Command> transformedCommand = transformCommandAndProcessJSON(channelUID, command);
 189         if (transformedCommand == null) {
 190             // We have, JSON as transform output (which has been processed) or some error. See
 191             // transformCommandAndProcessJSON javadoc
 192             return;
 193         }
 194
 195         // We did not have JSON output from the transformation, so writeStart is absolute required. Abort if it is
 196         // missing
 197         Integer writeStart = this.writeStart;
 198         if (writeStart == null) {
 199             logger.debug(
 200                     "Thing {} '{}': not processing command {} since writeStart is missing and transformation output is not a JSON",
 201                     getThing().getUID(), getThing().getLabel(), command);
 202             return;
 203         }
 204
 205         if (!transformedCommand.isPresent()) {
 206             // transformation failed, return
 207             logger.warn("Cannot process command {} (of type {}) with channel {} since transformation was unsuccessful",
 208                     command, command.getClass().getSimpleName(), channelUID);
 209             return;
 210         }
 211
 212         ModbusWriteRequestBlueprint request = requestFromCommand(channelUID, command, config, transformedCommand.get(),
 213                 writeStart);
 214         if (request == null) {
 215             return;
 216         }
 217
 218         logger.trace("Submitting write task {} to endpoint {}", request, comms.getEndpoint());
 219         comms.submitOneTimeWrite(request, this::onWriteResponse, this::handleWriteError);
 220     }
 221
 222     /**
 223      * Transform received command using the transformation.
 224      *
 225      * In case of JSON as transformation output, the output processed using {@link processJsonTransform}.
 226      *
 227      * @param channelUID channel UID corresponding to received command
 228      * @param command command to be transformed
 229      * @return transformed command. Null is returned with JSON transformation outputs and configuration errors
 230      *
 231      * @see processJsonTransform
 232      */
 233     private @Nullable Optional<Command> transformCommandAndProcessJSON(ChannelUID channelUID, Command command) {
 234         String transformOutput;
 235         Optional<Command> transformedCommand;
 236         Transformation writeTransformation = this.writeTransformation;
 237         if (writeTransformation == null || writeTransformation.isIdentityTransform()) {
 238             transformedCommand = Optional.of(command);
 239         } else {
 240             transformOutput = writeTransformation.transform(bundleContext, command.toString());
 241             if (transformOutput.contains("[")) {
 242                 processJsonTransform(command, transformOutput);
 243                 return null;
 244             } else if (writeParametersHavingTransformationOnly) {
 245                 updateStatusIfChanged(ThingStatus.OFFLINE, ThingStatusDetail.CONFIGURATION_ERROR, String.format(
 246                         "Seems to have writeTransformation but no other write parameters. Since the transformation did not return a JSON for command '%s' (channel %s), this is a configuration error",
 247                         command, channelUID));
 248                 return null;
 249             } else {
 250                 transformedCommand = Transformation.tryConvertToCommand(transformOutput);
 251                 logger.trace("Converted transform output '{}' to command '{}' (type {})", transformOutput,
 252                         transformedCommand.map(c -> c.toString()).orElse("<conversion failed>"),
 253                         transformedCommand.map(c -> c.getClass().getName()).orElse("<conversion failed>"));
 254             }
 255         }
 256         return transformedCommand;
 257     }
 258
 259     private @Nullable ModbusWriteRequestBlueprint requestFromCommand(ChannelUID channelUID, Command origCommand,
 260             ModbusDataConfiguration config, Command transformedCommand, Integer writeStart) {
 261         ModbusWriteRequestBlueprint request;
 262         boolean writeMultiple = config.isWriteMultipleEvenWithSingleRegisterOrCoil();
 263         String writeType = config.getWriteType();
 264         if (writeType == null) {
 265             return null;
 266         }
 267         if (writeType.equals(WRITE_TYPE_COIL)) {
 268             Optional<Boolean> commandAsBoolean = ModbusBitUtilities.translateCommand2Boolean(transformedCommand);
 269             if (!commandAsBoolean.isPresent()) {
 270                 logger.warn(
 271                         "Cannot process command {} with channel {} since command is not OnOffType, OpenClosedType or Decimal trying to write to coil. Do not know how to convert to 0/1. Transformed command was '{}'",
 272                         origCommand, channelUID, transformedCommand);
 273                 return null;
 274             }
 275             boolean data = commandAsBoolean.get();
 276             request = new ModbusWriteCoilRequestBlueprint(slaveId, writeStart, data, writeMultiple,
 277                     config.getWriteMaxTries());
 278         } else if (writeType.equals(WRITE_TYPE_HOLDING)) {
 279             ValueType writeValueType = this.writeValueType;
 280             if (writeValueType == null) {
 281                 // Should not happen in practice, since we are not in configuration error (checked above)
 282                 // This will make compiler happy anyways with the null checks
 283                 logger.warn("Received command but write value type not set! Ignoring command");
 284                 return null;
 285             }
 286             ModbusRegisterArray data = ModbusBitUtilities.commandToRegisters(transformedCommand, writeValueType);
 287             writeMultiple = writeMultiple || data.size() > 1;
 288             request = new ModbusWriteRegisterRequestBlueprint(slaveId, writeStart, data, writeMultiple,
 289                     config.getWriteMaxTries());
 290         } else {
 291             // Should not happen! This method is not called in case configuration errors and writeType is validated
 292             // already in initialization (validateAndParseWriteParameters).
 293             // We keep this here for future-proofing the code (new writeType values)
 294             throw new NotImplementedException(String.format(
 295                     "writeType does not equal %s or %s and thus configuration is invalid. Should not end up this far with configuration error.",
 296                     WRITE_TYPE_COIL, WRITE_TYPE_HOLDING));
 297         }
 298         return request;
 299     }
 300
 301     private void processJsonTransform(Command command, String transformOutput) {
 302         ModbusCommunicationInterface localComms = this.comms;
 303         if (localComms == null) {
 304             return;
 305         }
 306         Collection<ModbusWriteRequestBlueprint> requests;
 307         try {
 308             requests = WriteRequestJsonUtilities.fromJson(slaveId, transformOutput);
 309         } catch (IllegalArgumentException | IllegalStateException e) {
 310             logger.warn(
 311                     "Thing {} '{}' could handle transformation result '{}'. Original command {}. Error details follow",
 312                     getThing().getUID(), getThing().getLabel(), transformOutput, command, e);
 313             return;
 314         }
 315
 316         requests.stream().forEach(request -> {
 317             logger.trace("Submitting write request: {} to endpoint {} (based from transformation {})", request,
 318                     localComms.getEndpoint(), transformOutput);
 319             localComms.submitOneTimeWrite(request, this::onWriteResponse, this::handleWriteError);
 320         });
 321     }
 322
 323     @Override
 324     public synchronized void initialize() {
 325         // Initialize the thing. If done set status to ONLINE to indicate proper working.
 326         // Long running initialization should be done asynchronously in background.
 327         try {
 328             logger.trace("initialize() of thing {} '{}' starting", thing.getUID(), thing.getLabel());
 329             ModbusDataConfiguration localConfig = config = getConfigAs(ModbusDataConfiguration.class);
 330             updateUnchangedValuesEveryMillis = localConfig.getUpdateUnchangedValuesEveryMillis();
 331             Bridge bridge = getBridge();
 332             if (bridge == null || !bridge.getStatus().equals(ThingStatus.ONLINE)) {
 333                 logger.debug("Thing {} '{}' has no bridge or it is not online", getThing().getUID(),
 334                         getThing().getLabel());
 335                 updateStatusIfChanged(ThingStatus.OFFLINE, ThingStatusDetail.BRIDGE_OFFLINE, "No online bridge");
 336                 return;
 337             }
 338             BridgeHandler bridgeHandler = bridge.getHandler();
 339             if (bridgeHandler == null) {
 340                 logger.warn("Bridge {} '{}' has no handler.", bridge.getUID(), bridge.getLabel());
 341                 String errmsg = String.format("Bridge %s '%s' configuration incomplete or with errors", bridge.getUID(),
 342                         bridge.getLabel());
 343                 throw new ModbusConfigurationException(errmsg);
 344             }
 345             if (bridgeHandler instanceof ModbusEndpointThingHandler) {
 346                 // Write-only thing, parent is endpoint
 347                 ModbusEndpointThingHandler endpointHandler = (ModbusEndpointThingHandler) bridgeHandler;
 348                 slaveId = endpointHandler.getSlaveId();
 349                 comms = endpointHandler.getCommunicationInterface();
 350                 childOfEndpoint = true;
 351                 functionCode = null;
 352                 readRequest = null;
 353             } else {
 354                 ModbusPollerThingHandler localPollerHandler = (ModbusPollerThingHandler) bridgeHandler;
 355                 pollerHandler = localPollerHandler;
 356                 ModbusReadRequestBlueprint localReadRequest = localPollerHandler.getRequest();
 357                 if (localReadRequest == null) {
 358                     logger.debug(
 359                             "Poller {} '{}' has no read request -- configuration is changing or bridge having invalid configuration?",
 360                             bridge.getUID(), bridge.getLabel());
 361                     updateStatusIfChanged(ThingStatus.OFFLINE, ThingStatusDetail.BRIDGE_OFFLINE,
 362                             String.format("Poller %s '%s' has no poll task", bridge.getUID(), bridge.getLabel()));
 363                     return;
 364                 }
 365                 readRequest = localReadRequest;
 366                 slaveId = localReadRequest.getUnitID();
 367                 functionCode = localReadRequest.getFunctionCode();
 368                 comms = localPollerHandler.getCommunicationInterface();
 369                 pollStart = localReadRequest.getReference();
 370                 childOfEndpoint = false;
 371             }
 372             validateAndParseReadParameters(localConfig);
 373             validateAndParseWriteParameters(localConfig);
 374             validateMustReadOrWrite();
 375
 376             updateStatusIfChanged(ThingStatus.ONLINE);
 377         } catch (ModbusConfigurationException | EndpointNotInitializedException e) {
 378             logger.debug("Thing {} '{}' initialization error: {}", getThing().getUID(), getThing().getLabel(),
 379                     e.getMessage());
 380             updateStatusIfChanged(ThingStatus.OFFLINE, ThingStatusDetail.CONFIGURATION_ERROR, e.getMessage());
 381         } finally {
 382             logger.trace("initialize() of thing {} '{}' finished", thing.getUID(), thing.getLabel());
 383         }
 384     }
 385
 386     @Override
 387     public synchronized void dispose() {
 388         config = null;
 389         readValueType = null;
 390         writeValueType = null;
 391         readTransformation = null;
 392         writeTransformation = null;
 393         readIndex = Optional.empty();
 394         readSubIndex = Optional.empty();
 395         writeStart = null;
 396         pollStart = 0;
 397         slaveId = 0;
 398         comms = null;
 399         functionCode = null;
 400         readRequest = null;
 401         isWriteEnabled = false;
 402         isReadEnabled = false;
 403         writeParametersHavingTransformationOnly = false;
 404         childOfEndpoint = false;
 405         pollerHandler = null;
 406         channelCache = new HashMap<>();
 407         lastStatusInfoUpdate = LocalDateTime.MIN;
 408         statusInfo = new ThingStatusInfo(ThingStatus.UNKNOWN, ThingStatusDetail.NONE, null);
 409         channelLastUpdated = new HashMap<>(NUMER_OF_CHANNELS_HINT);
 410         channelLastState = new HashMap<>(NUMER_OF_CHANNELS_HINT);
 411     }
 412
 413     @Override
 414     public synchronized void bridgeStatusChanged(ThingStatusInfo bridgeStatusInfo) {
 415         logger.debug("bridgeStatusChanged for {}. Reseting handler", this.getThing().getUID());
 416         this.dispose();
 417         this.initialize();
 418     }
 419
 420     private boolean hasConfigurationError() {
 421         ThingStatusInfo statusInfo = getThing().getStatusInfo();
 422         return statusInfo.getStatus() == ThingStatus.OFFLINE
 423                 && statusInfo.getStatusDetail() == ThingStatusDetail.CONFIGURATION_ERROR;
 424     }
 425
 426     private void validateMustReadOrWrite() throws ModbusConfigurationException {
 427         if (!isReadEnabled && !isWriteEnabled) {
 428             throw new ModbusConfigurationException("Should try to read or write data!");
 429         }
 430     }
 431
 432     private void validateAndParseReadParameters(ModbusDataConfiguration config) throws ModbusConfigurationException {
 433         ModbusReadFunctionCode functionCode = this.functionCode;
 434         boolean readingDiscreteOrCoil = functionCode == ModbusReadFunctionCode.READ_COILS
 435                 || functionCode == ModbusReadFunctionCode.READ_INPUT_DISCRETES;
 436         boolean readStartMissing = StringUtils.isBlank(config.getReadStart());
 437         boolean readValueTypeMissing = StringUtils.isBlank(config.getReadValueType());
 438
 439         if (childOfEndpoint && readRequest == null) {
 440             if (!readStartMissing || !readValueTypeMissing) {
 441                 String errmsg = String.format(
 442                         "Thing %s readStart=%s, and readValueType=%s were specified even though the data thing is child of endpoint (that is, write-only)!",
 443                         getThing().getUID(), config.getReadStart(), config.getReadValueType());
 444                 throw new ModbusConfigurationException(errmsg);
 445             }
 446         }
 447
 448         // we assume readValueType=bit by default if it is missing
 449         boolean allMissingOrAllPresent = (readStartMissing && readValueTypeMissing)
 450                 || (!readStartMissing && (!readValueTypeMissing || readingDiscreteOrCoil));
 451         if (!allMissingOrAllPresent) {
 452             String errmsg = String.format(
 453                     "Thing %s readStart=%s, and readValueType=%s should be all present or all missing!",
 454                     getThing().getUID(), config.getReadStart(), config.getReadValueType());
 455             throw new ModbusConfigurationException(errmsg);
 456         } else if (!readStartMissing) {
 457             // all read values are present
 458             isReadEnabled = true;
 459             if (readingDiscreteOrCoil && readValueTypeMissing) {
 460                 readValueType = ModbusConstants.ValueType.BIT;
 461             } else {
 462                 try {
 463                     readValueType = ValueType.fromConfigValue(config.getReadValueType());
 464                 } catch (IllegalArgumentException e) {
 465                     String errmsg = String.format("Thing %s readValueType=%s is invalid!", getThing().getUID(),
 466                             config.getReadValueType());
 467                     throw new ModbusConfigurationException(errmsg);
 468                 }
 469             }
 470
 471             if (readingDiscreteOrCoil && !ModbusConstants.ValueType.BIT.equals(readValueType)) {
 472                 String errmsg = String.format(
 473                         "Thing %s invalid readValueType: Only readValueType='%s' (or undefined) supported with coils or discrete inputs. Value type was: %s",
 474                         getThing().getUID(), ModbusConstants.ValueType.BIT, config.getReadValueType());
 475                 throw new ModbusConfigurationException(errmsg);
 476             }
 477         } else {
 478             isReadEnabled = false;
 479         }
 480
 481         if (isReadEnabled) {
 482             String readStart = config.getReadStart();
 483             if (readStart == null) {
 484                 throw new ModbusConfigurationException(
 485                         String.format("Thing %s invalid readStart: %s", getThing().getUID(), config.getReadStart()));
 486             }
 487             String[] readParts = readStart.split("\\.", 2);
 488             try {
 489                 readIndex = Optional.of(Integer.parseInt(readParts[0]));
 490                 if (readParts.length == 2) {
 491                     readSubIndex = Optional.of(Integer.parseInt(readParts[1]));
 492                 } else {
 493                     readSubIndex = Optional.empty();
 494                 }
 495             } catch (IllegalArgumentException e) {
 496                 String errmsg = String.format("Thing %s invalid readStart: %s", getThing().getUID(),
 497                         config.getReadStart());
 498                 throw new ModbusConfigurationException(errmsg);
 499             }
 500         }
 501         readTransformation = new Transformation(config.getReadTransform());
 502         validateReadIndex();
 503     }
 504
 505     private void validateAndParseWriteParameters(ModbusDataConfiguration config) throws ModbusConfigurationException {
 506         boolean writeTypeMissing = StringUtils.isBlank(config.getWriteType());
 507         boolean writeStartMissing = StringUtils.isBlank(config.getWriteStart());
 508         boolean writeValueTypeMissing = StringUtils.isBlank(config.getWriteValueType());
 509         boolean writeTransformationMissing = StringUtils.isBlank(config.getWriteTransform());
 510         writeTransformation = new Transformation(config.getWriteTransform());
 511         boolean writingCoil = WRITE_TYPE_COIL.equals(config.getWriteType());
 512         writeParametersHavingTransformationOnly = (writeTypeMissing && writeStartMissing && writeValueTypeMissing
 513                 && !writeTransformationMissing);
 514         boolean allMissingOrAllPresentOrOnlyNonDefaultTransform = //
 515                 // read-only thing, no write specified
 516                 (writeTypeMissing && writeStartMissing && writeValueTypeMissing)
 517                         // mandatory write parameters provided. With coils one can drop value type
 518                         || (!writeTypeMissing && !writeStartMissing && (!writeValueTypeMissing || writingCoil))
 519                         // only transformation provided
 520                         || writeParametersHavingTransformationOnly;
 521         if (!allMissingOrAllPresentOrOnlyNonDefaultTransform) {
 522             String errmsg = String.format(
 523                     "writeType=%s, writeStart=%s, and writeValueType=%s should be all present, or all missing! Alternatively, you can provide just writeTransformation, and use transformation returning JSON.",
 524                     config.getWriteType(), config.getWriteStart(), config.getWriteValueType());
 525             throw new ModbusConfigurationException(errmsg);
 526         } else if (!writeTypeMissing || writeParametersHavingTransformationOnly) {
 527             isWriteEnabled = true;
 528             // all write values are present
 529             if (!writeParametersHavingTransformationOnly && !WRITE_TYPE_HOLDING.equals(config.getWriteType())
 530                     && !WRITE_TYPE_COIL.equals(config.getWriteType())) {
 531                 String errmsg = String.format("Invalid writeType=%s. Expecting %s or %s!", config.getWriteType(),
 532                         WRITE_TYPE_HOLDING, WRITE_TYPE_COIL);
 533                 throw new ModbusConfigurationException(errmsg);
 534             }
 535             final ValueType localWriteValueType;
 536             if (writeParametersHavingTransformationOnly) {
 537                 // Placeholder for further checks
 538                 localWriteValueType = writeValueType = ModbusConstants.ValueType.INT16;
 539             } else if (writingCoil && writeValueTypeMissing) {
 540                 localWriteValueType = writeValueType = ModbusConstants.ValueType.BIT;
 541             } else {
 542                 try {
 543                     localWriteValueType = writeValueType = ValueType.fromConfigValue(config.getWriteValueType());
 544                 } catch (IllegalArgumentException e) {
 545                     String errmsg = String.format("Invalid writeValueType=%s!", config.getWriteValueType());
 546                     throw new ModbusConfigurationException(errmsg);
 547                 }
 548             }
 549
 550             if (writingCoil && !ModbusConstants.ValueType.BIT.equals(localWriteValueType)) {
 551                 String errmsg = String.format(
 552                         "Invalid writeValueType: Only writeValueType='%s' (or undefined) supported with coils. Value type was: %s",
 553                         ModbusConstants.ValueType.BIT, config.getWriteValueType());
 554                 throw new ModbusConfigurationException(errmsg);
 555             } else if (!writingCoil && localWriteValueType.getBits() < 16) {
 556                 // trying to write holding registers with < 16 bit value types. Not supported
 557                 String errmsg = String.format(
 558                         "Invalid writeValueType: Only writeValueType with larger or equal to 16 bits are supported holding registers. Value type was: %s",
 559                         config.getWriteValueType());
 560                 throw new ModbusConfigurationException(errmsg);
 561             }
 562
 563             try {
 564                 if (!writeParametersHavingTransformationOnly) {
 565                     String localWriteStart = config.getWriteStart();
 566                     if (localWriteStart == null) {
 567                         String errmsg = String.format("Thing %s invalid writeStart: %s", getThing().getUID(),
 568                                 config.getWriteStart());
 569                         throw new ModbusConfigurationException(errmsg);
 570                     }
 571                     writeStart = Integer.parseInt(localWriteStart.trim());
 572                 }
 573             } catch (IllegalArgumentException e) {
 574                 String errmsg = String.format("Thing %s invalid writeStart: %s", getThing().getUID(),
 575                         config.getWriteStart());
 576                 throw new ModbusConfigurationException(errmsg);
 577             }
 578         } else {
 579             isWriteEnabled = false;
 580         }
 581     }
 582
 583     private void validateReadIndex() throws ModbusConfigurationException {
 584         @Nullable
 585         ModbusReadRequestBlueprint readRequest = this.readRequest;
 586         ValueType readValueType = this.readValueType;
 587         if (!readIndex.isPresent() || readRequest == null) {
 588             return;
 589         }
 590         assert readValueType != null;
 591         // bits represented by the value type, e.g. int32 -> 32
 592         int valueTypeBitCount = readValueType.getBits();
 593         int dataElementBits;
 594         switch (readRequest.getFunctionCode()) {
 595             case READ_INPUT_REGISTERS:
 596             case READ_MULTIPLE_REGISTERS:
 597                 dataElementBits = 16;
 598                 break;
 599             case READ_COILS:
 600             case READ_INPUT_DISCRETES:
 601                 dataElementBits = 1;
 602                 break;
 603             default:
 604                 throw new IllegalStateException(readRequest.getFunctionCode().toString());
 605         }
 606
 607         boolean bitQuery = dataElementBits == 1;
 608         if (bitQuery && readSubIndex.isPresent()) {
 609             String errmsg = String.format("readStart=X.Y is not allowed to be used with coils or discrete inputs!");
 610             throw new ModbusConfigurationException(errmsg);
 611         }
 612
 613         if (valueTypeBitCount >= 16 && readSubIndex.isPresent()) {
 614             String errmsg = String
 615                     .format("readStart=X.Y is not allowed to be used with value types larger than 16bit!");
 616             throw new ModbusConfigurationException(errmsg);
 617         } else if (!bitQuery && valueTypeBitCount < 16 && !readSubIndex.isPresent()) {
 618             String errmsg = String.format("readStart=X.Y must be used with value types less than 16bit!");
 619             throw new ModbusConfigurationException(errmsg);
 620         } else if (readSubIndex.isPresent() && (readSubIndex.get() + 1) * valueTypeBitCount > 16) {
 621             // the sub index Y (in X.Y) is above the register limits
 622             String errmsg = String.format("readStart=X.Y, the value Y is too large");
 623             throw new ModbusConfigurationException(errmsg);
 624         }
 625
 626         // Determine bit positions polled, both start and end inclusive
 627         int pollStartBitIndex = readRequest.getReference() * dataElementBits;
 628         int pollEndBitIndex = pollStartBitIndex + readRequest.getDataLength() * dataElementBits - 1;
 629
 630         // Determine bit positions read, both start and end inclusive
 631         int readStartBitIndex = readIndex.get() * dataElementBits + readSubIndex.orElse(0) * valueTypeBitCount;
 632         int readEndBitIndex = readStartBitIndex + valueTypeBitCount - 1;
 633
 634         if (readStartBitIndex < pollStartBitIndex || readEndBitIndex > pollEndBitIndex) {
 635             String errmsg = String.format(
 636                     "Out-of-bounds: Poller is reading from index %d to %d (inclusive) but this thing configured to read '%s' starting from element %d. Exceeds polled data bounds.",
 637                     pollStartBitIndex / dataElementBits, pollEndBitIndex / dataElementBits, readValueType,
 638                     readIndex.get());
 639             throw new ModbusConfigurationException(errmsg);
 640         }
 641     }
 642
 643     private boolean containsOnOff(List<Class<? extends State>> channelAcceptedDataTypes) {
 644         return channelAcceptedDataTypes.stream().anyMatch(clz -> {
 645             return clz.equals(OnOffType.class);
 646         });
 647     }
 648
 649     private boolean containsOpenClosed(List<Class<? extends State>> acceptedDataTypes) {
 650         return acceptedDataTypes.stream().anyMatch(clz -> {
 651             return clz.equals(OpenClosedType.class);
 652         });
 653     }
 654
 655     public synchronized void onReadResult(AsyncModbusReadResult result) {
 656         result.getRegisters().ifPresent(registers -> onRegisters(result.getRequest(), registers));
 657         result.getBits().ifPresent(bits -> onBits(result.getRequest(), bits));
 658     }
 659
 660     public synchronized void handleReadError(AsyncModbusFailure<ModbusReadRequestBlueprint> failure) {
 661         onError(failure.getRequest(), failure.getCause());
 662     }
 663
 664     public synchronized void handleWriteError(AsyncModbusFailure<ModbusWriteRequestBlueprint> failure) {
 665         onError(failure.getRequest(), failure.getCause());
 666     }
 667
 668     private synchronized void onRegisters(ModbusReadRequestBlueprint request, ModbusRegisterArray registers) {
 669         if (hasConfigurationError()) {
 670             return;
 671         } else if (!isReadEnabled) {
 672             return;
 673         }
 674         ValueType readValueType = this.readValueType;
 675         if (readValueType == null) {
 676             return;
 677         }
 678         State numericState;
 679
 680         // extractIndex:
 681         // e.g. with bit, extractIndex=4 means 5th bit (from right) ("10.4" -> 5th bit of register 10, "10.4" -> 5th bit
 682         // of register 10)
 683         // bit of second register)
 684         // e.g. with 8bit integer, extractIndex=3 means high byte of second register
 685         //
 686         // with <16 bit types, this is the index of the N'th 1-bit/8-bit item. Each register has 16/2 items,
 687         // respectively.
 688         // with >=16 bit types, this is index of first register
 689         int extractIndex;
 690         if (readValueType.getBits() >= 16) {
 691             // Invariant, checked in initialize
 692             assert readSubIndex.orElse(0) == 0;
 693             extractIndex = readIndex.get() - pollStart;
 694         } else {
 695             int subIndex = readSubIndex.orElse(0);
 696             int itemsPerRegister = 16 / readValueType.getBits();
 697             extractIndex = (readIndex.get() - pollStart) * itemsPerRegister + subIndex;
 698         }
 699         numericState = ModbusBitUtilities.extractStateFromRegisters(registers, extractIndex, readValueType)
 700                 .map(state -> (State) state).orElse(UnDefType.UNDEF);
 701         boolean boolValue = !numericState.equals(DecimalType.ZERO);
 702         Map<ChannelUID, State> values = processUpdatedValue(numericState, boolValue);
 703         logger.debug(
 704                 "Thing {} channels updated: {}. readValueType={}, readIndex={}, readSubIndex(or 0)={}, extractIndex={} -> numeric value {} and boolValue={}. Registers {} for request {}",
 705                 thing.getUID(), values, readValueType, readIndex, readSubIndex.orElse(0), extractIndex, numericState,
 706                 boolValue, registers, request);
 707     }
 708
 709     private synchronized void onBits(ModbusReadRequestBlueprint request, BitArray bits) {
 710         if (hasConfigurationError()) {
 711             return;
 712         } else if (!isReadEnabled) {
 713             return;
 714         }
 715         boolean boolValue = bits.getBit(readIndex.get() - pollStart);
 716         DecimalType numericState = boolValue ? new DecimalType(BigDecimal.ONE) : DecimalType.ZERO;
 717         Map<ChannelUID, State> values = processUpdatedValue(numericState, boolValue);
 718         logger.debug(
 719                 "Thing {} channels updated: {}. readValueType={}, readIndex={} -> numeric value {} and boolValue={}. Bits {} for request {}",
 720                 thing.getUID(), values, readValueType, readIndex, numericState, boolValue, bits, request);
 721     }
 722
 723     private synchronized void onError(ModbusReadRequestBlueprint request, Exception error) {
 724         if (hasConfigurationError()) {
 725             return;
 726         } else if (!isReadEnabled) {
 727             return;
 728         }
 729         if (error instanceof ModbusConnectionException) {
 730             logger.trace("Thing {} '{}' had {} error on read: {}", getThing().getUID(), getThing().getLabel(),
 731                     error.getClass().getSimpleName(), error.toString());
 732         } else if (error instanceof ModbusTransportException) {
 733             logger.trace("Thing {} '{}' had {} error on read: {}", getThing().getUID(), getThing().getLabel(),
 734                     error.getClass().getSimpleName(), error.toString());
 735         } else {
 736             logger.error(
 737                     "Thing {} '{}' had {} error on read: {} (message: {}). Stack trace follows since this is unexpected error.",
 738                     getThing().getUID(), getThing().getLabel(), error.getClass().getName(), error.toString(),
 739                     error.getMessage(), error);
 740         }
 741         Map<ChannelUID, State> states = new HashMap<>();
 742         ChannelUID lastReadErrorUID = getChannelUID(ModbusBindingConstantsInternal.CHANNEL_LAST_READ_ERROR);
 743         if (isLinked(lastReadErrorUID)) {
 744             states.put(lastReadErrorUID, new DateTimeType());
 745         }
 746
 747         synchronized (this) {
 748             // Update channels
 749             states.forEach((uid, state) -> {
 750                 tryUpdateState(uid, state);
 751             });
 752
 753             updateStatusIfChanged(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR,
 754                     String.format("Error (%s) with read. Request: %s. Description: %s. Message: %s",
 755                             error.getClass().getSimpleName(), request, error.toString(), error.getMessage()));
 756         }
 757     }
 758
 759     private synchronized void onError(ModbusWriteRequestBlueprint request, Exception error) {
 760         if (hasConfigurationError()) {
 761             return;
 762         } else if (!isWriteEnabled) {
 763             return;
 764         }
 765         if (error instanceof ModbusConnectionException) {
 766             logger.debug("Thing {} '{}' had {} error on write: {}", getThing().getUID(), getThing().getLabel(),
 767                     error.getClass().getSimpleName(), error.toString());
 768         } else if (error instanceof ModbusTransportException) {
 769             logger.debug("Thing {} '{}' had {} error on write: {}", getThing().getUID(), getThing().getLabel(),
 770                     error.getClass().getSimpleName(), error.toString());
 771         } else {
 772             logger.error(
 773                     "Thing {} '{}' had {} error on write: {} (message: {}). Stack trace follows since this is unexpected error.",
 774                     getThing().getUID(), getThing().getLabel(), error.getClass().getName(), error.toString(),
 775                     error.getMessage(), error);
 776         }
 777         Map<ChannelUID, State> states = new HashMap<>();
 778         ChannelUID lastWriteErrorUID = getChannelUID(ModbusBindingConstantsInternal.CHANNEL_LAST_WRITE_ERROR);
 779         if (isLinked(lastWriteErrorUID)) {
 780             states.put(lastWriteErrorUID, new DateTimeType());
 781         }
 782
 783         synchronized (this) {
 784             // Update channels
 785             states.forEach((uid, state) -> {
 786                 tryUpdateState(uid, state);
 787             });
 788
 789             updateStatusIfChanged(ThingStatus.OFFLINE, ThingStatusDetail.COMMUNICATION_ERROR,
 790                     String.format("Error (%s) with write. Request: %s. Description: %s. Message: %s",
 791                             error.getClass().getSimpleName(), request, error.toString(), error.getMessage()));
 792         }
 793     }
 794
 795     public synchronized void onWriteResponse(AsyncModbusWriteResult result) {
 796         if (hasConfigurationError()) {
 797             return;
 798         } else if (!isWriteEnabled) {
 799             return;
 800         }
 801         logger.debug("Successful write, matching request {}", result.getRequest());
 802         updateStatusIfChanged(ThingStatus.ONLINE);
 803         ChannelUID lastWriteSuccessUID = getChannelUID(ModbusBindingConstantsInternal.CHANNEL_LAST_WRITE_SUCCESS);
 804         if (isLinked(lastWriteSuccessUID)) {
 805             updateState(lastWriteSuccessUID, new DateTimeType());
 806         }
 807     }
 808
 809     /**
 810      * Update linked channels
 811      *
 812      * @param numericState numeric state corresponding to polled data (or UNDEF with floating point NaN or infinity)
 813      * @param boolValue boolean value corresponding to polled data
 814      * @return updated channel data
 815      */
 816     private Map<ChannelUID, State> processUpdatedValue(State numericState, boolean boolValue) {
 817         Transformation localReadTransformation = readTransformation;
 818         if (localReadTransformation == null) {
 819             // We should always have transformation available if thing is initalized properly
 820             logger.trace("No transformation available, aborting processUpdatedValue");
 821             return Collections.emptyMap();
 822         }
 823         Map<ChannelUID, State> states = new HashMap<>();
 824         CHANNEL_ID_TO_ACCEPTED_TYPES.keySet().stream().forEach(channelId -> {
 825             ChannelUID channelUID = getChannelUID(channelId);
 826             if (!isLinked(channelUID)) {
 827                 return;
 828             }
 829             List<Class<? extends State>> acceptedDataTypes = CHANNEL_ID_TO_ACCEPTED_TYPES.get(channelId);
 830             if (acceptedDataTypes.isEmpty()) {
 831                 return;
 832             }
 833
 834             State boolLikeState;
 835             if (containsOnOff(acceptedDataTypes)) {
 836                 boolLikeState = boolValue ? OnOffType.ON : OnOffType.OFF;
 837             } else if (containsOpenClosed(acceptedDataTypes)) {
 838                 boolLikeState = boolValue ? OpenClosedType.OPEN : OpenClosedType.CLOSED;
 839             } else {
 840                 boolLikeState = null;
 841             }
 842
 843             State transformedState;
 844             if (localReadTransformation.isIdentityTransform()) {
 845                 if (boolLikeState != null) {
 846                     // A bit of smartness for ON/OFF and OPEN/CLOSED with boolean like items
 847                     transformedState = boolLikeState;
 848                 } else {
 849                     // Numeric states always go through transformation. This allows value of 17.5 to be
 850                     // converted to
 851                     // 17.5% with percent types (instead of raising error)
 852                     transformedState = localReadTransformation.transformState(bundleContext, acceptedDataTypes,
 853                             numericState);
 854                 }
 855             } else {
 856                 transformedState = localReadTransformation.transformState(bundleContext, acceptedDataTypes,
 857                         numericState);
 858             }
 859
 860             if (transformedState != null) {
 861                 logger.trace(
 862                         "Channel {} will be updated to '{}' (type {}). Input data: number value {} (value type '{}' taken into account) and bool value {}. Transformation: {}",
 863                         channelId, transformedState, transformedState.getClass().getSimpleName(), numericState,
 864                         readValueType, boolValue,
 865                         localReadTransformation.isIdentityTransform() ? "<identity>" : localReadTransformation);
 866                 states.put(channelUID, transformedState);
 867             } else {
 868                 String types = StringUtils.join(acceptedDataTypes.stream().map(cls -> cls.getSimpleName()).toArray(),
 869                         ", ");
 870                 logger.warn(
 871                         "Channel {} will not be updated since transformation was unsuccessful. Channel is expecting the following data types [{}]. Input data: number value {} (value type '{}' taken into account) and bool value {}. Transformation: {}",
 872                         channelId, types, numericState, readValueType, boolValue,
 873                         localReadTransformation.isIdentityTransform() ? "<identity>" : localReadTransformation);
 874             }
 875         });
 876
 877         ChannelUID lastReadSuccessUID = getChannelUID(ModbusBindingConstantsInternal.CHANNEL_LAST_READ_SUCCESS);
 878         if (isLinked(lastReadSuccessUID)) {
 879             states.put(lastReadSuccessUID, new DateTimeType());
 880         }
 881         updateExpiredChannels(states);
 882         return states;
 883     }
 884
 885     private void updateExpiredChannels(Map<ChannelUID, State> states) {
 886         synchronized (this) {
 887             updateStatusIfChanged(ThingStatus.ONLINE);
 888             long now = System.currentTimeMillis();
 889             // Update channels that have not been updated in a while, or when their values has changed
 890             states.forEach((uid, state) -> updateExpiredChannel(now, uid, state));
 891             channelLastState = states;
 892         }
 893     }
 894
 895     // since lastState can be null, and "lastState == null" in conditional is not useless
 896     @SuppressWarnings("null")
 897     private void updateExpiredChannel(long now, ChannelUID uid, State state) {
 898         @Nullable
 899         State lastState = channelLastState.get(uid);
 900         long lastUpdatedMillis = channelLastUpdated.getOrDefault(uid, 0L);
 901         long millisSinceLastUpdate = now - lastUpdatedMillis;
 902         if (lastUpdatedMillis <= 0L || lastState == null || updateUnchangedValuesEveryMillis <= 0L
 903                 || millisSinceLastUpdate > updateUnchangedValuesEveryMillis || !lastState.equals(state)) {
 904             tryUpdateState(uid, state);
 905             channelLastUpdated.put(uid, now);
 906         }
 907     }
 908
 909     private void tryUpdateState(ChannelUID uid, State state) {
 910         try {
 911             updateState(uid, state);
 912         } catch (IllegalArgumentException e) {
 913             logger.warn("Error updating state '{}' (type {}) to channel {}: {} {}", state,
 914                     Optional.ofNullable(state).map(s -> s.getClass().getName()).orElse("null"), uid,
 915                     e.getClass().getName(), e.getMessage());
 916         }
 917     }
 918
 919     private ChannelUID getChannelUID(String channelID) {
 920         return Objects
 921                 .requireNonNull(channelCache.computeIfAbsent(channelID, id -> new ChannelUID(getThing().getUID(), id)));
 922     }
 923
 924     private void updateStatusIfChanged(ThingStatus status) {
 925         updateStatusIfChanged(status, ThingStatusDetail.NONE, null);
 926     }
 927
 928     private void updateStatusIfChanged(ThingStatus status, ThingStatusDetail statusDetail,
 929             @Nullable String description) {
 930         ThingStatusInfo newStatusInfo = new ThingStatusInfo(status, statusDetail, description);
 931         Duration durationSinceLastUpdate = Duration.between(lastStatusInfoUpdate, LocalDateTime.now());
 932         boolean intervalElapsed = MIN_STATUS_INFO_UPDATE_INTERVAL.minus(durationSinceLastUpdate).isNegative();
 933         if (statusInfo.getStatus() == ThingStatus.UNKNOWN || !statusInfo.equals(newStatusInfo) || intervalElapsed) {
 934             statusInfo = newStatusInfo;
 935             lastStatusInfoUpdate = LocalDateTime.now();
 936             updateStatus(newStatusInfo);
 937         }
 938     }
 939
 940     /**
 941      * Update status using pre-constructed ThingStatusInfo
 942      *
 943      * Implementation adapted from BaseThingHandler updateStatus implementations
 944      *
 945      * @param statusInfo new status info
 946      */
 947     protected void updateStatus(ThingStatusInfo statusInfo) {
 948         synchronized (this) {
 949             ThingHandlerCallback callback = getCallback();
 950             if (callback != null) {
 951                 callback.statusUpdated(this.thing, statusInfo);
 952             } else {
 953                 logger.warn("Handler {} tried updating the thing status although the handler was already disposed.",
 954                         this.getClass().getSimpleName());
 955             }
 956         }
 957     }
 958 }