uk.org.retep.util.monitor
Class ProgressListenerSet

java.lang.Object
  uk.org.retep.util.concurrent.ReadWriteConcurrencySupport
      uk.org.retep.util.concurrent.ConcurrencySupport
          uk.org.retep.util.monitor.ProgressListenerSet

All Implemented Interfaces:

ProgressListener

@ThreadSafe
public class ProgressListenerSet
extends ConcurrencySupport
implements ProgressListener

A set of ProgressListener's that will receive the same events as received by this class. This enables more than one ProgressListener to be attached to a monitored process.

Author:

peter

Constructor Summary

ProgressListenerSet()

ProgressListenerSet(ProgressListener... listeners)

Method Summary

boolean	add(ProgressListener l) Add a ProgressListener to the set
static ProgressListener	add(ProgressListener current, ProgressListener listener) Utility method that allows a ProgressListener to be added to an existing ProgressListener using the following schematics: If the current listener is null then this returns the new listener.
ProgressListener[]	getListeners() Returns a snapshot of the ProgressListener's currently in the set
boolean	isEmpty() Is the set empty.
boolean	remove(ProgressListener l) Remove a ProgressListener from the set
static ProgressListener	remove(ProgressListener current, ProgressListener listener) Utility method that removes a ProgressListener from the current ProgressListener if that instance is a ProgressListenerSet.
void	setMaximum(long maximum) Notify the listeners that the maximum value has changed
void	setMaximum(long inputMaximum, long outputMaximum) Notify the listeners that the maximum value has changed
void	showProgress(int progress) Notify listeners of the current progress.
void	showProgress(long inputSize, long outputSize) Notify listners of the current progress.
int	size() The number of ProgressListener's in this set.

Methods inherited from class uk.org.retep.util.concurrent.ConcurrencySupport

getLog

Methods inherited from class uk.org.retep.util.concurrent.ReadWriteConcurrencySupport

readLock, writeLock

Methods inherited from class java.lang.Object

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

Constructor Detail

ProgressListenerSet

public ProgressListenerSet()

ProgressListenerSet

public ProgressListenerSet(ProgressListener... listeners)

Method Detail

add

public static ProgressListener add(ProgressListener current,
                                   ProgressListener listener)

Utility method that allows a ProgressListener to be added to an existing ProgressListener using the following schematics:

1. If the current listener is null then this returns the new listener.
2. If the current listener is an instance of ProgressListenerSet then the new listener is added to it and the current listener is returned.
3. If neither of the above are met a new ProgressListenerSet is created, and both the current and new listeners are added to it and the set is returned.

For example, a monotored process has an addProgressListener() method:

 private ProgressListener listener;

 public void addProgressListener( final ProgressListener newListener )
 {
      listener = ProgressListenerSet.add( listener, newListener );
 }
 

Parameters:

current - The current ProgressListener

listener - The ProgressListener to add

Returns:

a ProgressListener

Throws:

java.lang.IllegalArgumentException - if newListener is null

remove

public static ProgressListener remove(ProgressListener current,
                                      ProgressListener listener)

Utility method that removes a ProgressListener from the current ProgressListener if that instance is a ProgressListenerSet.

For example, a monotored process has an removeProgressListener() method:

 private ProgressListener listener;

 public void removeProgressListener( final ProgressListener newListener )
 {
      listener = ProgressListenerSet.remove( listener, newListener );
 }
 

Parameters:

current -

listener -

Returns:

add

@WriteLock
public boolean add(ProgressListener l)

Add a ProgressListener to the set

Parameters:

l - ProgressListener to add

Returns:

true if the set was modified

remove

@WriteLock
public boolean remove(ProgressListener l)

Remove a ProgressListener from the set

Parameters:

l - ProgressListener to remove

Returns:

true if the set was modified

isEmpty

@ReadLock
public boolean isEmpty()

Is the set empty. This value is a snapshot so is for informational use only.

Returns:

true if the set is empty

size

@ReadLock
public int size()

The number of ProgressListener's in this set. This value is a snapshot so is for informational use only.

Returns:

getListeners

@ReadLock
public ProgressListener[] getListeners()

Returns a snapshot of the ProgressListener's currently in the set

Returns:

array of ProgressListener's

showProgress

public void showProgress(int progress)

Description copied from interface: ProgressListener

Notify listeners of the current progress.

Specified by:

showProgress in interface ProgressListener

Parameters:

progress - The current value of the process

showProgress

public void showProgress(long inputSize,
                         long outputSize)

Description copied from interface: ProgressListener

Notify listners of the current progress. This method is normall used by compression routines so the listener knows how much the input has been compressed by

Specified by:

showProgress in interface ProgressListener

Parameters:

inputSize - The current size of the input, possibly the amount read so far

outputSize - The current size of the output, probably the total size of the compressed output

setMaximum

public void setMaximum(long maximum)

Description copied from interface: ProgressListener

Notify the listeners that the maximum value has changed

Specified by:

setMaximum in interface ProgressListener

Parameters:

maximum - The new maximum

setMaximum

public void setMaximum(long inputMaximum,
                       long outputMaximum)

Description copied from interface: ProgressListener

Notify the listeners that the maximum value has changed

Specified by:

setMaximum in interface ProgressListener

Parameters:

inputMaximum - The new maximum for the input

outputMaximum - The new maximum for the output.