uk.org.ogsadai.persistence.file.activity
Class SimpleFileActivitySpecDAO

java.lang.Object
  uk.org.ogsadai.persistence.file.SimpleFileDAO
      uk.org.ogsadai.persistence.file.activity.SimpleFileActivitySpecDAO

All Implemented Interfaces:

java.util.EventListener, ActivityEventListener, ActivitySpecDAO, DAO, FilePersistenceConfiguration

public class SimpleFileActivitySpecDAO
extends SimpleFileDAO
implements ActivitySpecDAO, ActivityEventListener

This class manages the persistence of activity-related information within configuration files. It populates objects with state from persistence media and also persists state represented by objects. The DAO records itself as a listener to any ActivitySpec objects it provides or is given and, depending upon the persistence policy in place, will react to changes in the activity specification and persist such changes. The activity-related file is expected to be called activties.txt and be within a configuration directory provided to this class. The file is expected to have the following format:

 # Activity ID
 # A value compliant with the format of uk.org.ogsadai.activity.ActivityID.
 id=ACTIVITY-ID
 # Activity implementation class name.
 class=ACTIVITY-CLASS
 # Human-readable description.
 description=ACTIVITY-DESCRIPTION
 CONFIG
 # Activity configuration - specific to implementation class.
 # Zero or more key-value properties.
 # Key must be compliant with uk.org.ogsadai.common.Key.
 # Value can be a string, boolean or number.
 KEY1=VALUE1
 KEY2=VALUE2
 KEY3=VALUE3
 ...
 END
 ...
 

For example:

 id=uk.org.ogsadai.SQLQueryActivity
 class=uk.org.ogsadai.activity.sql.SQLQueryActivity
 description=A standard SQL query activity.
 CONFIG
 default.fetch.size=1234
 max.fetch.size=5678
 END
 id=uk.org.ogsadai.XSLTransformActivity
 class=uk.org.ogsadai.activity.transform.XSLTransformActivity
 description=An XSL transform activity.
 CONFIG
 END
 ...
 

This class does not support auto-detection of changes to configuration files.

Author:

The OGSA-DAI Project Team

Field Summary

Fields inherited from class uk.org.ogsadai.persistence.file.SimpleFileDAO

mConfigDir, mFileUtils

Constructor Summary

SimpleFileActivitySpecDAO()
Constructor.

SimpleFileActivitySpecDAO(java.io.File configDir)
Constructor.

Method Summary

void	activityUpdated(ActivityUpdateEvent event) Inform a component that an activity-related component changed state.
void	deleteActivitySpec(ActivityID activityID) Delete the specification of an activity.
ActivitySpec	getActivitySpec(ActivityID activityID) This class will register itself as a listener for changes in the ActivitySpec returned.
boolean	hasPersistedStateChanged(ActivityID activityID) This class does not support auto-detection of changes to configuration files.
void	insertActivitySpec(ActivitySpec activitySpec) If activitySpec implements ActivityEventDispatcher then this class will register itself as a listener.
boolean	isActivityKnown(ActivityID activityID) Is an activity recorded in the persistence media?
java.util.List	listActivities() Get a list of activities persisted in the persistence media.
void	setConfigDir(java.io.File configDir) Set the configuration directory.

Methods inherited from class uk.org.ogsadai.persistence.file.SimpleFileDAO

getConfigDir

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleFileActivitySpecDAO

public SimpleFileActivitySpecDAO()

Constructor.

SimpleFileActivitySpecDAO

public SimpleFileActivitySpecDAO(java.io.File configDir)

Constructor.

Parameters:

configDir - Configuration directory

Throws:

java.lang.IllegalArgumentException - If configDir is null.

Method Detail

setConfigDir

public void setConfigDir(java.io.File configDir)

Description copied from interface: FilePersistenceConfiguration

Set the configuration directory.

Specified by:

setConfigDir in interface FilePersistenceConfiguration

Overrides:

setConfigDir in class SimpleFileDAO

Parameters:

configDir - Configuration directory.

listActivities

public java.util.List listActivities()
                              throws PersistenceException

Description copied from interface: ActivitySpecDAO

Get a list of activities persisted in the persistence media.

Specified by:

listActivities in interface ActivitySpecDAO

Returns:

List<ActivityID>

Throws:

PersistenceException - If any problems arise when interacting with the persistence media.

isActivityKnown

public boolean isActivityKnown(ActivityID activityID)
                        throws PersistenceException

Description copied from interface: ActivitySpecDAO

Is an activity recorded in the persistence media?

Specified by:

isActivityKnown in interface ActivitySpecDAO

Parameters:

activityID - Activity ID

Returns:

true if the activity is known.

Throws:

java.lang.IllegalArgumentException - If activityID is null.

PersistenceException - If any problems arise when interacting with the persistence media.

getActivitySpec

public ActivitySpec getActivitySpec(ActivityID activityID)
                             throws ActivityUnknownException,
                                    PersistenceException

This class will register itself as a listener for changes in the ActivitySpec returned.

Specified by:

getActivitySpec in interface ActivitySpecDAO

Parameters:

activityID - Activity ID

Returns:

activity specification.

Throws:

java.lang.IllegalArgumentException - If activityID is null.

ActivityUnknownException - If the activity is unknown i.e. not recorded in the persistence media.

PersistenceException - If any problems arise when interacting with the persistence media.

deleteActivitySpec

public void deleteActivitySpec(ActivityID activityID)
                        throws PersistenceException

Description copied from interface: ActivitySpecDAO

Delete the specification of an activity.

Specified by:

deleteActivitySpec in interface ActivitySpecDAO

Parameters:

activityID - Activity ID

Throws:

java.lang.IllegalArgumentException - If activitySpec is null.

PersistenceException - If any problems arise when interacting with the persistence media.

insertActivitySpec

public void insertActivitySpec(ActivitySpec activitySpec)
                        throws PersistenceException

If activitySpec implements ActivityEventDispatcher then this class will register itself as a listener.

Specified by:

insertActivitySpec in interface ActivitySpecDAO

Parameters:

activitySpec - Activity specification

Throws:

java.lang.IllegalArgumentException - If activitySpec is null.

PersistenceException - If any problems arise when interacting with the persistence media.

activityUpdated

public void activityUpdated(ActivityUpdateEvent event)

Description copied from interface: ActivityEventListener

Inform a component that an activity-related component changed state.

Specified by:

activityUpdated in interface ActivityEventListener

Parameters:

event - Information on the update.

Throws:

java.lang.IllegalArgumentException - If event is null.

PersistenceException - If any problems arise when interacting with the persistence media.

hasPersistedStateChanged

public boolean hasPersistedStateChanged(ActivityID activityID)
                                 throws PersistenceException

This class does not support auto-detection of changes to configuration files.

Specified by:

hasPersistedStateChanged in interface ActivitySpecDAO

Parameters:

activityID - Activity ID

Returns:

false always.

Throws:

PersistenceException - If any problems arise when interacting with the persistence media.