org.eclipse.rwt.service
Class FileSettingStore

java.lang.Object
  org.eclipse.rwt.service.FileSettingStore

All Implemented Interfaces:

ISettingStore

public final class FileSettingStore
extends java.lang.Object
implements ISettingStore

This ISettingStore implementation persists all settings on the file system using Java Properties.

Since:

1.1

Field Summary

static java.lang.String

FILE_SETTING_STORE_DIR This key (value "org.eclipse.rwt.service.FileSettingStore.dir") can be used to configure the working directory for file settings stores.

Constructor Summary

FileSettingStore(java.io.File workDir)
Create a FileSettingStore instance.

Method Summary

void	addSettingStoreListener(SettingStoreListener listener) Attaches an SettingStoreListener to this ISettingStore.
java.lang.String	getAttribute(java.lang.String name) Returns the attribute stored under the specified name in this ISettingStore, or null if no attribute is stored under that name.
java.util.Enumeration	getAttributeNames() Returns an Enumeration of String objects with the names of all attributes in this ISettingStore.
java.lang.String	getId() Returns the unique identifier of this setting store
void	loadById(java.lang.String id) Replace the contents of this setting store with all attributes persisted under the given id.
void	removeAttribute(java.lang.String name) Removes the attribute stored under the specified name from this ISettingStore.
void	removeSettingStoreListener(SettingStoreListener listener) Removes an SettingStoreListener from this ISettingStore.
void	setAttribute(java.lang.String name, java.lang.String value) Stores an attribute to this ISettingStore, using the name specified.

Methods inherited from class java.lang.Object

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

Field Detail

FILE_SETTING_STORE_DIR

public static final java.lang.String FILE_SETTING_STORE_DIR

This key (value "org.eclipse.rwt.service.FileSettingStore.dir") can be used to configure the working directory for file settings stores. See RWTFileSettingStoreFactory and WorkbenchFileSettingStoreFactory.

See Also:

Constant Field Values

Constructor Detail

FileSettingStore

public FileSettingStore(java.io.File workDir)

Create a FileSettingStore instance. The store will be initialized with a unique random id and will contain no attributes. Use loadById(String) to initialize an existing store with previously persisted attributes.

Parameters:

workDir - a non-null File instance denoting an existing directory, which will be used by this class persist its settings.

Throws:

java.lang.NullPointerException - if the argument workDir is null

java.lang.IllegalArgumentException - if the argument workDir is not a directory

See Also:

loadById(String)

Method Detail

getId

public java.lang.String getId()

Description copied from interface: ISettingStore

Returns the unique identifier of this setting store

Specified by:

getId in interface ISettingStore

Returns:

a non-empty String value; never null

getAttribute

public java.lang.String getAttribute(java.lang.String name)

Description copied from interface: ISettingStore

Returns the attribute stored under the specified name in this ISettingStore, or null if no attribute is stored under that name.

Specified by:

getAttribute in interface ISettingStore

Parameters:

name - a non-null String specifying the name of the attribute

Returns:

a String value or null

setAttribute

public void setAttribute(java.lang.String name,
                         java.lang.String value)
                  throws SettingStoreException

Description copied from interface: ISettingStore

Stores an attribute to this ISettingStore, using the name specified. If an attribute with the same name is already stored in that ISettingStore the previous value is replaced.

Any attribute stored to this ISettingStore using this method is considered persisted from that point on.

If the value argument is null, this has the same effect as calling ISettingStore.removeAttribute(String).

SettingStoreListeners attached to this instance will be notified after an attribute has been stored.

Specified by:

setAttribute in interface ISettingStore

Parameters:

name - the name of the attribute; cannot be null

value - the String to store; may be null

Throws:

SettingStoreException - if the load operation failed to complete normally

getAttributeNames

public java.util.Enumeration getAttributeNames()

Description copied from interface: ISettingStore

Returns an Enumeration of String objects with the names of all attributes in this ISettingStore.

Specified by:

getAttributeNames in interface ISettingStore

Returns:

an Enumeration; never null

loadById

public void loadById(java.lang.String id)
              throws SettingStoreException

Description copied from interface: ISettingStore

Replace the contents of this setting store with all attributes persisted under the given id.

The attributes of this setting store before the load operation will remain associated with the old id, but will be removed from this store instance. SettingStoreListeners attached to this store will receive a notification for each removed attribute.

During the load operation this store will be filled with the attributes associated with the new id value. SettingStoreListeners attached to this store will receive a notification for each added attribute.

After the load operation this store will only hold attributes associated with the new id value.

It is important to note that this operation does not create a new setting store, so that listeners still remain associated with the same store instance. Instead the contents of this setting store are replaced with the contents associated with the given id.

Specified by:

loadById in interface ISettingStore

Parameters:

id - a non-null; non-empty; non-whitespace-only String

Throws:

SettingStoreException - if the load operation failed to complete normally

removeAttribute

public void removeAttribute(java.lang.String name)
                     throws SettingStoreException

Description copied from interface: ISettingStore

Removes the attribute stored under the specified name from this ISettingStore. If no attribute is stored under the specified name, this method does nothing.

SettingStoreListeners attached to this instance will be notified after an attribute has been removed.

Specified by:

removeAttribute in interface ISettingStore

Parameters:

name - the name of the attribute to remove; cannot be null

Throws:

SettingStoreException - if the remove operation failed to complete normally

addSettingStoreListener

public void addSettingStoreListener(SettingStoreListener listener)

Description copied from interface: ISettingStore

Attaches an SettingStoreListener to this ISettingStore.

Listeners attached to this instance will notified of changes in the store.

Specified by:

addSettingStoreListener in interface ISettingStore

Parameters:

listener - the SettingStoreListener to add; non-null

removeSettingStoreListener

public void removeSettingStoreListener(SettingStoreListener listener)

Description copied from interface: ISettingStore

Removes an SettingStoreListener from this ISettingStore.

Specified by:

removeSettingStoreListener in interface ISettingStore

Parameters:

listener - the SettingStoreListener to remove; non-null