本人在上文中提到，连接器实现了两种事件依赖的机制 ，其一是我们手动操作连接器实例时；其二是由连接器的自动更新机制

上文中分析了连接器的自动更新机制，即定时器执行定时任务

那么，如果我们手动操作连接器实例时，是怎么发出事件更新连接器实例的呢

通过eclipse开发工具，追踪调用ChangeDetector接口的detect()方法的方法

ChangeDetectorTask类的run方法里面调用我们再上文中已经分析了，其他方法便是ConnectorCoordinatorImpl实例对象的方法

即ConnectorCoordinatorImpl实例对象的如下方法，分别调用了ChangeDetector接口的detect()方法

/**   * 移除连接器实例   * Removes this {
    @link Connector} instance.  Halts traversals,   * removes the Connector instance from the known connectors,   * and removes the Connector's on-disk representation.   */  /* @Override */  public void removeConnector() {    synchronized(this) {      resetBatch();      if (instanceInfo != null) {        instanceInfo.removeConnector();      }    }    // This must not be called while holding the lock.    changeDetector.detect();  }/**   * 重启遍历   * Retraverses the {
    @link Connector}'s content from scratch.   * Halts any traversal in progress and removes any saved traversal state,   * forcing the Connector to retraverse the Repository from its start.   */  /* @Override */  public void restartConnectorTraversal() throws ConnectorNotFoundException {    // To avoid deadlock, this method calls InstanceInfo's getters and setters,    // rather than the local ones.    synchronized(this) {      resetBatch();                               // Halt any traversal.      getInstanceInfo().setConnectorState(null);  // Discard the checkpoint.      // If Schedule was 'run-once', re-enable it to run again.  But watch out -      // empty disabled Schedules could look a bit like a run-once Schedule.      Schedule schedule = getInstanceInfo().getConnectorSchedule();      if (schedule != null && schedule.isDisabled() &&            schedule.getRetryDelayMillis() == -1 &&            schedule.nextScheduledInterval() != -1) {          schedule.setDisabled(false);          getInstanceInfo().setConnectorSchedule(schedule);      }    }    // TODO: Remove this if we switch completely to JDBC PersistentStore.    // FileStore doesn't notice the deletion of a file that did not exist.    if (lister != null) {      connectorCheckpointChanged(null);    }    // This must not be called while holding the lock.    changeDetector.detect();  }/**   * 设置配置信息   * Sets the {
    @link Configuration} for this {
    @link ConnectorCoordinator}.   * If this {
    @link ConnectorCoordinator} supports persistence this will   * persist the new Configuration.   */  /* @Override */  public ConfigureResponse setConnectorConfiguration(TypeInfo newTypeInfo,      Configuration configuration, Locale locale, boolean update)      throws ConnectorNotFoundException, ConnectorExistsException,      InstantiatorException {    LOGGER.info("Configuring connector " + name);    String typeName = newTypeInfo.getConnectorTypeName();    Preconditions.checkArgument(typeName.equals(configuration.getTypeName()),        "TypeInfo must match Configuration type");    ConfigureResponse response = null;    synchronized(this) {      resetBatch();      if (instanceInfo != null) {        if (!update) {          throw new ConnectorExistsException();        }        if (typeName.equals(typeInfo.getConnectorTypeName())) {          configuration =              new Configuration(configuration, getConnectorConfiguration());          response = resetConfig(instanceInfo.getConnectorDir(), typeInfo,              configuration, locale);        } else {          // An existing connector is being given a new type - drop then add.          // TODO: This shouldn't be called from within the synchronized block          // because it will kick the change detector.          removeConnector();          response = createNewConnector(newTypeInfo, configuration, locale);          if (response != null) {            // TODO: We need to restore original Connector config. This is            // necessary once we allow update a Connector with new ConnectorType.            // However, when doing so consider: createNewConnector could have            // thrown InstantiatorException as well.  Also, you need to kick            // the changeDetector (but not in this synchronized block).            LOGGER.severe("Failed to update Connector configuration.");            //    + " Restoring original Connector configuration.");          }        }      } else {        if (update) {          throw new ConnectorNotFoundException();        }        response = createNewConnector(newTypeInfo, configuration, locale);      }    }    if (response == null) {      // This must not be called while holding the lock.      changeDetector.detect();    } else {      return new ExtendedConfigureResponse(response, configuration.getXml());    }    return response;  }/**   * 设置定时调度   * Sets the traversal {
    @link Schedule} for the {
    @link Connector}.   *   * @param connectorSchedule Schedule to store or null to unset any existing   *        Schedule.   * @throws ConnectorNotFoundException if the connector is not found   */  /* @Override */  public void setConnectorSchedule(Schedule connectorSchedule)      throws ConnectorNotFoundException {    synchronized(this) {      // Persistently store the new schedule.      getInstanceInfo().setConnectorSchedule(connectorSchedule);    }    // This must not be called while holding the lock.    changeDetector.detect();  }

接下来ChangeDetector接口的detect()方法其实又调用了自身的实现ConnectorCoordinatorImpl实例对象的实现ChangeHandler接口的方法

ConnectorCoordinatorImpl-->ChangeDetector的detect()-->ChangeListener的相关方法-->ChangeHandler(ConnectorCoordinatorImpl实例对象)的相关方法

所以手动操作与自动更新机制实际上是殊途同归，最后都是调用了ChangeHandler(ConnectorCoordinatorImpl实例对象)的相关方法

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