Implementation of the metrics package that writes the metrics to a file. Programmers should not normally need to use this package directly. Instead they should use org.hadoop.metrics.

These are the implementation specific factory attributes (See ContextFactory.getFactory()):

contextName.fileName
  The path of the file to which metrics in context contextName are to be appended. If this attribute is not specified, the metrics are written to standard output by default.
contextName.period
  The period in seconds on which the metric data is written to the file.