Package org.apache.hadoop.metrics2.impl

Class MetricsSystemImpl

java.lang.Object
org.apache.hadoop.metrics2.MetricsSystem
org.apache.hadoop.metrics2.impl.MetricsSystemImpl
All Implemented Interfaces:
MetricsSource, MetricsSystemMXBean
@Private @Metrics(context="metricssystem") public class MetricsSystemImpl extends MetricsSystem implements MetricsSource
A base class for metrics system singletons

  • Constructor Details

    • MetricsSystemImpl

      public MetricsSystemImpl(String prefix)
      Construct the metrics system
      Parameters:
      prefix - for the system

    • MetricsSystemImpl

      public MetricsSystemImpl()
      Construct the system but not initializing (read config etc.) it.

  • Method Details

    • init

      public MetricsSystem init(String prefix)
      Initialized the metrics system with a prefix.
      Specified by:
      init in class MetricsSystem
      Parameters:
      prefix - the system will look for configs with the prefix
      Returns:
      the metrics system object itself

    • start

      public void start()
      Description copied from interface: MetricsSystemMXBean
      Start the metrics system
      Specified by:
      start in interface MetricsSystemMXBean

    • stop

      public void stop()
      Description copied from interface: MetricsSystemMXBean
      Stop the metrics system
      Specified by:
      stop in interface MetricsSystemMXBean

    • register

      public <T> T register(String name, String desc, T source)
      Description copied from class: MetricsSystem
      Register a metrics source
      Specified by:
      register in class MetricsSystem
      Type Parameters:
      T - the actual type of the source object
      Parameters:
      name - of the source. Must be unique or null (then extracted from the annotations of the source object.)
      desc - the description of the source (or null. See above.)
      source - object to register
      Returns:
      the source object

    • unregisterSource

      public void unregisterSource(String name)
      Description copied from class: MetricsSystem
      Unregister a metrics source
      Specified by:
      unregisterSource in class MetricsSystem
      Parameters:
      name - of the source. This is the name you use to call register()

    • register

      public <T extends MetricsSink> T register(String name, String description, T sink)
      Description copied from class: MetricsSystem
      Register a metrics sink
      Specified by:
      register in class MetricsSystem
      Type Parameters:
      T - the type of the sink
      Parameters:
      name - of the sink. Must be unique.
      description - the description of the sink
      sink - to register
      Returns:
      the sink

    • register

      public void register(MetricsSystem.Callback callback)
      Description copied from class: MetricsSystem
      Register a callback interface for JMX events
      Specified by:
      register in class MetricsSystem
      Parameters:
      callback - the callback object implementing the MBean interface.

    • startMetricsMBeans

      public void startMetricsMBeans()
      Description copied from interface: MetricsSystemMXBean
      Start metrics MBeans
      Specified by:
      startMetricsMBeans in interface MetricsSystemMXBean

    • stopMetricsMBeans

      public void stopMetricsMBeans()
      Description copied from interface: MetricsSystemMXBean
      Stop metrics MBeans. Note, it doesn't stop the metrics system control MBean, i.e this interface.
      Specified by:
      stopMetricsMBeans in interface MetricsSystemMXBean

    • currentConfig

      public String currentConfig()
      Specified by:
      currentConfig in interface MetricsSystemMXBean
      Returns:
      the current config Avoided getConfig, as it'll turn into a "Config" attribute, which doesn't support multiple line values in jconsole.

    • publishMetricsNow

      public void publishMetricsNow()
      Requests an immediate publish of all metrics from sources to sinks.
      Specified by:
      publishMetricsNow in class MetricsSystem

    • sampleMetrics

      @VisibleForTesting public org.apache.hadoop.metrics2.impl.MetricsBuffer sampleMetrics()
      Sample all the sources for a snapshot of metrics/tags
      Returns:
      the metrics buffer containing the snapshot

    • getMetrics

      public void getMetrics(MetricsCollector builder, boolean all)
      Description copied from interface: MetricsSource
      Get metrics from the metrics source
      Specified by:
      getMetrics in interface MetricsSource
      Parameters:
      builder - to contain the resulting metrics snapshot
      all - if true, return all metrics even if unchanged.

    • shutdown

      public boolean shutdown()
      Description copied from class: MetricsSystem
      Shutdown the metrics system completely (usually during server shutdown.) The MetricsSystemMXBean will be unregistered.
      Specified by:
      shutdown in class MetricsSystem
      Returns:
      true if shutdown completed

    • getSource

      public MetricsSource getSource(String name)
      Specified by:
      getSource in class MetricsSystem
      Parameters:
      name - of the metrics source
      Returns:
      the metrics source (potentially wrapped) object

    • getSinkAdapter

      @VisibleForTesting public org.apache.hadoop.metrics2.impl.MetricsSinkAdapter getSinkAdapter(String name)