org.apache.excalibur.instrument

Class ValueInstrument

java.lang.Object

org.apache.excalibur.instrument.AbstractInstrument

org.apache.excalibur.instrument.ValueInstrument

All Implemented Interfaces:

Instrument

public class ValueInstrument
extends AbstractInstrument

Objects implementing Instrumentable can create Instruments with integer values using a ValueInstrument. ValueInstruments are perfect for profiling things like system memory, or the size of a pool or cache.

Since:

4.1

Version:

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

Author:

Avalon Development Team

Constructor Summary

Constructors

Constructor and Description
ValueInstrument(java.lang.String name) Creates a new ValueInstrument.

Method Summary

Methods

Modifier and Type	Method and Description
void	setValue(int value) Sets the current value of the Instrument.

Methods inherited from class org.apache.excalibur.instrument.AbstractInstrument

getInstrumentName, getInstrumentProxy, isActive, setInstrumentProxy

Methods inherited from class java.lang.Object

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

Constructor Detail

ValueInstrument

public ValueInstrument(java.lang.String name)

Creates a new ValueInstrument.

Parameters:

name - The name of the Instrument. The value should be a string which does not contain spaces or periods.

Method Detail

setValue

public void setValue(int value)

Sets the current value of the Instrument. This method is optimized to be extremely light weight when an InstrumentManager is not present and there are no registered ValueInstrumentListeners.

Note that in many cases is best to call this method even if the isActive() method returns false. This is because the InstrumentManager will remember the last value set and use it if the instrument ever becomes active. For things like pool sizes which do not change often, this behavior is critical so that users can begin monitoring the value and see what it was before they connected. Setting the value is very light weight, but its calculation may not be. It is up to the user to weigh the benefits and consequences one way or the other.

Parameters:

value - The new value for the Instrument.