org.apache.excalibur.instrument.manager.impl
Class InstrumentProxy

java.lang.Object
  org.apache.avalon.framework.logger.AbstractLogEnabled
      org.apache.excalibur.instrument.manager.impl.InstrumentProxy

All Implemented Interfaces:

Configurable, InstrumentProxy, LogEnabled

public class InstrumentProxy

extends AbstractLogEnabled

implements InstrumentProxy, Configurable

Instrumentables which do not implement ThreadSafe may have multiple instances created by the ComponentLocator. Each of these Instruments will share a common key and are instrumented as a group. The InstrumentProxy is used make it easy for the InstrumentManager to control groups of Instruments as one.

The type of a Instrument can not be determined at configuration time. It is resolved when the Instrumentable actually registers the Instrument.

Since:

4.1

Version:

CVS $Revision: 1.4 $ $Date: 2004/02/28 11:47:25 $

Author:

Avalon Development Team

Method Summary

void	configure(Configuration configuration) Configures the Instrument.
void	enableLogging(Logger logger) Set the components logger.
static java.lang.String	getTypeName(int type) Returns the name of a Instrument type.
void	increment(int count) Increments the Instrument by a specified count.
boolean	isActive() Used by classes being instrumented so that they can avoid unnecessary code when the data from a Instrument is not being used.
void	setValue(int value) Sets the current value of the Instrument.
protected void	stateChanged() Called whenever the state of the instrument is changed.

Methods inherited from class org.apache.avalon.framework.logger.AbstractLogEnabled

getLogger, setupLogger, setupLogger, setupLogger

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

enableLogging

public void enableLogging(Logger logger)

Description copied from class: AbstractLogEnabled

Set the components logger.

Specified by:

enableLogging in interface LogEnabled

Overrides:

enableLogging in class AbstractLogEnabled

Parameters:

logger - the logger

configure

public void configure(Configuration configuration)
               throws ConfigurationException

Configures the Instrument. Called from the InstrumentManager's configure method. The class does not need to be configured to function correctly.

Specified by:

configure in interface Configurable

Parameters:

configuration - Instrument configuration element from the InstrumentManager's configuration.

Throws:

ConfigurationException - If there are any configuration problems.

isActive

public boolean isActive()

Used by classes being instrumented so that they can avoid unnecessary code when the data from a Instrument is not being used.

Specified by:

isActive in interface InstrumentProxy

Returns:

True if listeners are registered with the Instrument.

increment

public void increment(int count)

Increments the Instrument by a specified count. This method should be optimized to be extremely light weight when there are no registered CounterInstrumentListeners.

Specified by:

increment in interface InstrumentProxy

Parameters:

count - A positive integer to increment the counter by.

setValue

public void setValue(int value)

Sets the current value of the Instrument. This method is optimized to be extremely light weight when there are no registered ValueInstrumentListeners.

Specified by:

setValue in interface InstrumentProxy

Parameters:

value - The new value for the Instrument.

stateChanged

protected void stateChanged()

Called whenever the state of the instrument is changed.

getTypeName

public static java.lang.String getTypeName(int type)

Returns the name of a Instrument type.

Parameters:

type - Type whose name is wanted.

Returns:

The name of a Instrument type.