rs.baselib.prefs

Class AbstractPreferencesService

java.lang.Object

rs.baselib.prefs.AbstractPreferencesService

All Implemented Interfaces:

IPreferencesService

Direct Known Subclasses:

PreferencesService

public abstract class AbstractPreferencesService
extends Object
implements IPreferencesService

Common functionality of a preferences service. The service organizes all preferences in this scheme:

    /@application1/@USER   - user preferences of application 1
    /@application1/@SYSTEM - system preferences of application 1
    /@application2/@USER   - user preferences of application 2
    /@application2/@SYSTEM - system preferences of application 2
 

Author:

ralph

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	AbstractPreferencesService.FlushingThread A thread running all flushs.

Constructor Summary

Constructors

Constructor and Description
AbstractPreferencesService() Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
protected static void	checkNodeName(String s) Checks the name of the node to be correct.
protected ReadWriteLock	createReadWriteLock() Creates a new ReadWriteLock.
protected abstract IPreferences	createRootNode() Creates the root node.
void	flush(IPreferences node) Flushes any changes made in this node.
protected abstract void	flushSystemPreferences(IPreferences node, String applicationName) Flushes the system preferences from the given node.
protected abstract void	flushUserPreferences(IPreferences node, String applicationName) Flushes the user preferences from the given node.
protected String	getApplicationName(IPreferences node) Returns the application name of the given node.
protected IPreferences	getApplicationNode(IPreferences node) Returns the application node rom the given node
protected IPreferences	getApplicationPreferences(String applicationName) Returns the application preferences.
protected IPreferences	getLockNode(IPreferences node) Returns the node where locks will be placed upon.
Lock	getReadLock(IPreferences node) Returns the read lock object for the given node.
protected ReadWriteLock	getReadWriteLock(IPreferences node) Returns the correct lock for the given node.
IPreferences	getSystemPreferences(String applicationName) Returns the system preferences for the given application.
IPreferences	getUserPreferences(String applicationName) Returns the user preferences for the given application.
Lock	getWriteLock(IPreferences node) Returns the write lock object for the given node.
protected abstract void	loadSystemPreferences(IPreferences node, String applicationName) Loads the system preferences into the given node.
protected abstract void	loadUserPreferences(IPreferences node, String applicationName) Loads the user preferences into the given node.
void	nodeChanged(IPreferences node) A node changed.
void	sync(IPreferences node) Wait for any modifications to be flushed.

Methods inherited from class java.lang.Object

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

Methods inherited from interface rs.baselib.prefs.IPreferencesService

getSystemPreferencesHome, getUserPreferencesHome

Constructor Detail

AbstractPreferencesService

public AbstractPreferencesService()

Constructor.

Method Detail

createRootNode

protected abstract IPreferences createRootNode()

Creates the root node.

Returns:

the root node for the service

getApplicationPreferences

protected IPreferences getApplicationPreferences(String applicationName)
                                          throws BackingStoreException

Returns the application preferences.

Parameters:

applicationName - name of application

Returns:

the root node for this application

Throws:

BackingStoreException

createReadWriteLock

protected ReadWriteLock createReadWriteLock()

Creates a new ReadWriteLock.

Returns:

a new ReentrantReadWriteLock

getReadLock

public Lock getReadLock(IPreferences node)

Returns the read lock object for the given node.

Specified by:

getReadLock in interface IPreferencesService

Parameters:

node - the node that requires a read lock

Returns:

the responsible Lock object

getWriteLock

public Lock getWriteLock(IPreferences node)

Returns the write lock object for the given node.

Specified by:

getWriteLock in interface IPreferencesService

Parameters:

node - the node that requires a write lock

Returns:

the responsible Lock object

getReadWriteLock

protected ReadWriteLock getReadWriteLock(IPreferences node)

Returns the correct lock for the given node.

Parameters:

node - node to get the lock for

Returns:

the ReadWriteLock

getLockNode

protected IPreferences getLockNode(IPreferences node)

Returns the node where locks will be placed upon.

Parameters:

node - the node where a lock is required

Returns:

the node that needs to be locked

loadUserPreferences

protected abstract void loadUserPreferences(IPreferences node,
                       String applicationName)
                                     throws BackingStoreException

Loads the user preferences into the given node.

Parameters:

node - node that shall be populated

applicationName - name of application to be loaded

Throws:

BackingStoreException

loadSystemPreferences

protected abstract void loadSystemPreferences(IPreferences node,
                         String applicationName)
                                       throws BackingStoreException

Loads the system preferences into the given node.

Parameters:

node - node that shall be populated

applicationName - name of application to be loaded

Throws:

BackingStoreException

flushUserPreferences

protected abstract void flushUserPreferences(IPreferences node,
                        String applicationName)
                                      throws BackingStoreException

Flushes the user preferences from the given node.

Parameters:

node - node that shall be flushed

applicationName - name of application to be flushed

Throws:

BackingStoreException

flushSystemPreferences

protected abstract void flushSystemPreferences(IPreferences node,
                          String applicationName)
                                        throws BackingStoreException

Flushes the system preferences from the given node.

Parameters:

node - node that shall be flushed

applicationName - name of application to be flushed

Throws:

BackingStoreException

getUserPreferences

public IPreferences getUserPreferences(String applicationName)
                                throws BackingStoreException

Returns the user preferences for the given application.

Specified by:

getUserPreferences in interface IPreferencesService

Parameters:

applicationName - name of application

Throws:

BackingStoreException

getSystemPreferences

public IPreferences getSystemPreferences(String applicationName)
                                  throws BackingStoreException

Returns the system preferences for the given application.

Specified by:

getSystemPreferences in interface IPreferencesService

Parameters:

applicationName - name of application

Throws:

BackingStoreException

checkNodeName

protected static void checkNodeName(String s)

Checks the name of the node to be correct. A node name must not contain whitespaces or special characters other than '@', '-' or '-' or '.'.

Parameters:

s - string to be checked

nodeChanged

public void nodeChanged(IPreferences node)

A node changed. Schedules a flush.

Parameters:

node - the node that changed

flush

public void flush(IPreferences node)
           throws BackingStoreException

Flushes any changes made in this node. The method does not return before the flush has been completed.

Specified by:

flush in interface IPreferencesService

Parameters:

node - the node to be flushed

Throws:

BackingStoreException - when there has been a communication problem with the backing store.

getApplicationNode

protected IPreferences getApplicationNode(IPreferences node)

Returns the application node rom the given node

Parameters:

node - child node

Returns:

the application node

getApplicationName

protected String getApplicationName(IPreferences node)

Returns the application name of the given node.

Parameters:

node - any child node

Returns:

the application name this node belongs to

sync

public void sync(IPreferences node)
          throws BackingStoreException

Wait for any modifications to be flushed. The method does not return before the next flush has been completed (in case modifications are pending).

Specified by:

sync in interface IPreferencesService

Parameters:

node - the node to be flushed

Throws:

BackingStoreException - when there has been a communication problem with the backing store.