Class NullContextWithUpdateThread

  extended by org.apache.hadoop.metrics.spi.AbstractMetricsContext
      extended by org.apache.hadoop.metrics.spi.NullContextWithUpdateThread
All Implemented Interfaces:

public class NullContextWithUpdateThread
extends AbstractMetricsContext

A null context which has a thread calling periodically when monitoring is started. This keeps the data sampled correctly. In all other respects, this is like the NULL context: No data is emitted. This is suitable for Monitoring systems like JMX which reads the metrics when someone reads the data from JMX. The default impl of start and stop monitoring: is the AbstractMetricsContext is good enough.

Field Summary
Fields inherited from interface org.apache.hadoop.metrics.MetricsContext
Constructor Summary
          Creates a new instance of NullContextWithUpdateThread
Method Summary
Methods inherited from class org.apache.hadoop.metrics.spi.AbstractMetricsContext
close, createRecord, flush, getAllRecords, getAttribute, getAttributeTable, getContextFactory, getContextName, getPeriod, isMonitoring, newRecord, parseAndSetPeriod, registerUpdater, setPeriod, startMonitoring, stopMonitoring, unregisterUpdater
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


public NullContextWithUpdateThread()
Creates a new instance of NullContextWithUpdateThread

Copyright © 2013 Apache Software Foundation. All Rights Reserved.