Package com.mapr.org.apache.hadoop.metrics

Interface MetricsContext

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int DEFAULT_PERIOD
      Default period in seconds at which data is sent to the metrics system.

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void close()
      Stops monitoring and also frees any buffered data, returning this object to its initial state.
      MetricsRecord createRecord​(java.lang.String recordName)
      Creates a new MetricsRecord instance with the given recordName.
      java.util.Map<java.lang.String,​java.util.Collection<OutputRecord>> getAllRecords()
      Retrieves all the records managed by this MetricsContext.
      java.lang.String getContextName()
      Returns the context name.
      int getPeriod()
      Returns the timer period.
      void init​(java.lang.String contextName, ContextFactory factory)
      Initialize this context.
      boolean isMonitoring()
      Returns true if monitoring is currently in progress.
      void registerUpdater​(Updater updater)
      Registers a callback to be called at regular time intervals, as determined by the implementation-class specific configuration.
      void startMonitoring()
      Starts or restarts monitoring, the emitting of metrics records as they are updated.
      void stopMonitoring()
      Stops monitoring.
      void unregisterUpdater​(Updater updater)
      Removes a callback, if it exists.

    • Field Detail

      • DEFAULT_PERIOD

        static final int DEFAULT_PERIOD
        Default period in seconds at which data is sent to the metrics system.
        See Also:
        Constant Field Values

    • Method Detail

      • init

        void init​(java.lang.String contextName,
          ContextFactory factory)
        Initialize this context.
        Parameters:
        contextName - The given name for this context
        factory - The creator of this context

      • getContextName

        java.lang.String getContextName()
        Returns the context name.
        Returns:
        the context name

      • startMonitoring

        void startMonitoring()
              throws java.io.IOException
        Starts or restarts monitoring, the emitting of metrics records as they are updated.
        Throws:
        java.io.IOException

      • stopMonitoring

        void stopMonitoring()
        Stops monitoring. This does not free any data that the implementation may have buffered for sending at the next timer event. It is OK to call startMonitoring() again after calling this.
        See Also:
        close()

      • isMonitoring

        boolean isMonitoring()
        Returns true if monitoring is currently in progress.

      • close

        void close()
        Stops monitoring and also frees any buffered data, returning this object to its initial state.

      • createRecord

        MetricsRecord createRecord​(java.lang.String recordName)
        Creates a new MetricsRecord instance with the given recordName. Throws an exception if the metrics implementation is configured with a fixed set of record names and recordName is not in that set.
        Parameters:
        recordName - the name of the record
        Throws:
        MetricsException - if recordName conflicts with configuration data

      • registerUpdater

        void registerUpdater​(Updater updater)
        Registers a callback to be called at regular time intervals, as determined by the implementation-class specific configuration.
        Parameters:
        updater - object to be run periodically; it should updated some metrics records and then return

      • unregisterUpdater

        void unregisterUpdater​(Updater updater)
        Removes a callback, if it exists.
        Parameters:
        updater - object to be removed from the callback list

      • getPeriod

        int getPeriod()
        Returns the timer period.

      • getAllRecords

        java.util.Map<java.lang.String,​java.util.Collection<OutputRecord>> getAllRecords()
        Retrieves all the records managed by this MetricsContext. Useful for monitoring systems that are polling-based.
        Returns:
        A non-null map from all record names to the records managed.