File	Doc	Category	Size	Date	Package
MutableCountStatisticImpl.java	API Doc	Glassfish v2 API	6861	Fri May 04 22:25:48 BST 2007	com.sun.enterprise.admin.monitor.stats

MutableCountStatisticImpl

• java.lang.Object

Fields Summary
private final javax.management.j2ee.statistics.CountStatistic	initial
private long	count
private long	lastSampleTime
private long	startTime

Constructors Summary

public MutableCountStatisticImpl(javax.management.j2ee.statistics.CountStatistic initial) Constructs an instance of MutableCountStatistic that encapsulates the given Statistic. The only parameter denotes the initial state of this statistic. It is guaranteed that the initial state is preserved internally, so that one can reset to the initial state. param initial an instance of CountStatistic that represents initial state this.initial = initial; this.count = initial.getCount(); this.lastSampleTime = initial.getLastSampleTime(); this.startTime = lastSampleTime;

Methods Summary
public long	getCount() return ( this.count );
public java.lang.String	getDescription() return ( initial.getDescription() );
public long	getLastSampleTime() return ( this.lastSampleTime );
public java.lang.String	getName() return ( initial.getName() );
public long	getStartTime() return ( this.startTime );
public java.lang.String	getUnit() return ( initial.getUnit());
public javax.management.j2ee.statistics.Statistic	modifiableView() return ( this );
public void	reset() Resets to the initial state. It is guaranteed that following changes occur to the statistic if this method is called: The current value is reset to its initial value. The lastSampleTime is reset to current time in milliseconds. The startTime is reset to lastSampleTime. The remaining meta data in the statistic is unchanged. this.count = initial.getCount(); this.lastSampleTime = System.currentTimeMillis(); this.startTime = this.lastSampleTime;
public void	setCount(long count) Changes the value of the encapsulated CountStatistic to the given value. Since this is the only mutator exposed here, here are the other side effects of calling this method: lastSampleTime is set to current time in milliseconds. In a real-time system with actual probes for measurement, the lastSampleTime could be different from the instant when this method is called, but that is deemed insignificant. param count long that represents the current value of the Statistic. this.count = count; this.lastSampleTime = System.currentTimeMillis();
public void	setDescription(java.lang.String s) try { ((StatisticImpl)this.initial).setDescription(s); } catch(final Exception e) { }
public javax.management.j2ee.statistics.Statistic	unmodifiableView() This method is the essence of this class. It provides the read-only view of encapsulated Statistic. If the clients have to know the Statistic, this is what should be called by actual data collecting component to return the value to them. The principle advantage is from the data collecting component's standpoint, in that it does not have to create instances of CountStatistic when its current value is queried/measured. see #reset see #setCount return instance of CountStatistic return ( new CountStatisticImpl( this.count, // this is the actual changing statistic initial.getName(), // name does not change initial.getUnit(), // unit does not change initial.getDescription(), // description does not change this.lastSampleTime, // changes all the time! this.startTime // changes if reset is called earlier ));