Nepomuk::ResourceWatcher Class Reference

#include <resourcewatcher.h>

Inheritance diagram for Nepomuk::ResourceWatcher:

Public Slots
void	addProperty (const Types::Property &property)
void	addResource (const Nepomuk::Resource &res)
void	addType (const Types::Class &type)
QList< Types::Property >	properties () const
int	propertyCount () const
void	removeProperty (const Types::Property &property)
void	removeResource (const Nepomuk::Resource &res)
void	removeType (const Types::Class &type)
int	resourceCount () const
QList< Nepomuk::Resource >	resources () const
void	setProperties (const QList< Types::Property > &properties_)
void	setResources (const QList< Nepomuk::Resource > &resources_)
void	setTypes (const QList< Types::Class > &types_)
bool	start ()
void	stop ()
int	typeCount () const
QList< Types::Class >	types () const

Signals
void	propertyAdded (const Nepomuk::Resource &resource, const Nepomuk::Types::Property &property, const QVariant &value)
void	propertyChanged (const Nepomuk::Resource &resource, const Nepomuk::Types::Property &property, const QVariantList &oldValue, const QVariantList &newValue)
void	propertyRemoved (const Nepomuk::Resource &resource, const Nepomuk::Types::Property &property, const QVariant &value)
void	resourceCreated (const Nepomuk::Resource &resource, const QList< QUrl > &types)
void	resourceRemoved (const QUrl &uri, const QList< QUrl > &types)
void	resourceTypeAdded (const Nepomuk::Resource &res, const Types::Class &type)
void	resourceTypeRemoved (const Nepomuk::Resource &res, const Types::Class &type)

Public Member Functions
	ResourceWatcher (QObject *parent=0)
virtual	~ResourceWatcher ()

Detailed Description

Selectively monitor the nepomuk repository for changes.

Resources may be monitored on the basis of types, properties, and uris.

Changes may be monitored in one of the following ways:

1. By resources - Specify the exact resources that should be watched. Any changes made to the specified resources (Excluding nepomuk_dms_metadata) will be notified through the propertyAdded() and propertyRemoved() signals. Notifications will also be sent if any of the watched resources is deleted.
2. By resources and properties - Specify the exact resources and their properties. Any changes made to the specified resources which touch one of the specified properties will be notified through the propertyAdded() and propertyRemoved() signals.
3. By types - Specific types may be specified via add/setType. If types are set, then notifications will be sent for all new resources of that type. This includes property changes and resource creation and removal. TODO: add flags that allow to only watch for resource creation and removal.
4. By types and properties - Both the types and properties may be specified. Notifications will be sent for property changes in resource with the specified types.

Resource Watcher Usage Example

The following code creates a new ResourceWatcher, configures it to listen to changes on the nmm:performer property on one specific resource res.

Nepomuk::ResourceWatcher* watcher = new Nepomuk::ResourceWatcher(this);
watcher->addResource(res);
watcher->addProperty(NMM:performer());
connect(watcher, SIGNAL(propertyAdded(Nepomuk::Resource, Nepomuk::Types::Property, QVariant)),
        this, SLOT(slotPropertyChanged()));
connect(watcher, SIGNAL(propertyRemoved(Nepomuk::Resource, Nepomuk::Types::Property, QVariant)),
        this, SLOT(slotPropertyChanged()));
rwatcher->start();

Author

Vishesh Handa handa.nosp@m..vis.nosp@m.h@gma.nosp@m.il.c.nosp@m.om, Sebastian Trueg trueg.nosp@m.@kde.nosp@m..org

Definition at line 78 of file resourcewatcher.h.

Constructor & Destructor Documentation

Nepomuk::ResourceWatcher::ResourceWatcher

(

QObject *

parent = 0

)

Create a new ResourceWatcher instance.

This instance will not emit any signals before it has been configured and started.

virtual Nepomuk::ResourceWatcher::~ResourceWatcher ( )

virtual

Destructor.

Member Function Documentation

void Nepomuk::ResourceWatcher::addProperty ( const Types::Property &  property )

slot

Add a property to be watched.

Every change to a value of this property will be signalled, depending on the configured resources() or types().

See also

setProperties()

void Nepomuk::ResourceWatcher::addResource ( const Nepomuk::Resource &  res )

slot

Add a resource to be watched.

Every change to this resource will be signalled, depending on the configured properties().

See also

setResources()

void Nepomuk::ResourceWatcher::addType ( const Types::Class &  type )

slot

Add a type to be watched.

Every resource of this type will be watched for changes.

See also

setTypes()

QList<Types::Property> Nepomuk::ResourceWatcher::properties ( ) const

slot

The properties that have been configured via addProperty() and setProperties().

Every change to a value of any of these properties will be signalled, depending on the configured resources() or types().

void Nepomuk::ResourceWatcher::propertyAdded ( const Nepomuk::Resource &  resource, const Nepomuk::Types::Property &  property, const QVariant &  value  )

signal

This signal is emitted when a property value is added.

Parameters

resource	The changed resource.
property	The property which has a new value.
value	The newly added property value.

void Nepomuk::ResourceWatcher::propertyChanged ( const Nepomuk::Resource &  resource, const Nepomuk::Types::Property &  property, const QVariantList &  oldValue, const QVariantList &  newValue  )

signal

This signal is emitted when a property value is changed.

This signal cannot be emitted for all changes. It doesn't work if a property is first removed and then set, cause the Data Mangement Service does not maintain an internal cache for the purpose of emitting the propertyChanged signal.

Specially, since one could theoretically take forever between the removal and the setting of the property.

Parameters

resource	The changed resource.
property	The property which was changed.
oldValue	The removed property value.

int Nepomuk::ResourceWatcher::propertyCount ( ) const

slot

Return the number of properties that are being watched.

This method is slightly faster than called properties().count()

See also

properties addProperty setProperty

void Nepomuk::ResourceWatcher::propertyRemoved ( const Nepomuk::Resource &  resource, const Nepomuk::Types::Property &  property, const QVariant &  value  )

signal

This signal is emitted when a property value is removed.

Parameters

resource	The changed resource.
property	The property which was changed.
value	The removed property value.

void Nepomuk::ResourceWatcher::removeProperty ( const Types::Property &  property )

slot

Remove a property to be watched.

Every change to a value of this property will be signalled, depending on the configured resources() or types().

See also

setProperties()

void Nepomuk::ResourceWatcher::removeResource ( const Nepomuk::Resource &  res )

slot

Remove a resource to be watched.

Every change to this resource will be signalled, depending on the configured properties().

See also

setResources()

void Nepomuk::ResourceWatcher::removeType ( const Types::Class &  type )

slot

Remove a type to be watched.

Every resource of this type will be watched for changes.

See also

setTypes()

int Nepomuk::ResourceWatcher::resourceCount ( ) const

slot

Return the number of resources that are being watched.

This method is slightly faster than called resources().count()

See also

resources addResource setResources

void Nepomuk::ResourceWatcher::resourceCreated ( const Nepomuk::Resource &  resource, const QList< QUrl > &  types  )

signal

This signal is emitted when a new resource is created.

Parameters

resource	The newly created resource.
types	The types the new resource has. If types() have been configured this list will always contain one of the configured types.

void Nepomuk::ResourceWatcher::resourceRemoved ( const QUrl &  uri, const QList< QUrl > &  types  )

signal

This signal is emitted when a resource is deleted.

Parameters

uri	The resource URI of the removed resource.
types	The types the removed resource had. If types() have been configured this list will always contain one of the configured types.

QList<Nepomuk::Resource> Nepomuk::ResourceWatcher::resources ( ) const

slot

The resources that have been configured via addResource() and setResources().

Every change to one of these resources will be signalled, depending on the configured properties().

void Nepomuk::ResourceWatcher::resourceTypeAdded ( const Nepomuk::Resource &  res, const Types::Class &  type  )

signal

This signal is emitted when a type has been added to a resource.

This does not include creation which is signalled via resourceCreated(). It only applies to changes in a resource's types.

Parameters

res	The changed resource.
type	The newly added type. If types() have been configured it will be one of them.

void Nepomuk::ResourceWatcher::resourceTypeRemoved ( const Nepomuk::Resource &  res, const Types::Class &  type  )

signal

This signal is emitted when a type has been removed from a resource.

This does not include removal of entire resources which is signalled via resourceRemoved(). It only applies to changes in a resource's types.

Parameters

res	The changed resource.
type	The removed type. If types() have been configured it will be one of them.

void Nepomuk::ResourceWatcher::setProperties ( const QList< Types::Property > &  properties_ )

slot

Set the properties to be watched.

Every change to a value of any of these properties will be signalled, depending on the configured resources() or types().

See also

addProperty()

void Nepomuk::ResourceWatcher::setResources ( const QList< Nepomuk::Resource > &  resources_ )

slot

Set the resources to be watched.

Every change to one of these resources will be signalled, depending on the configured properties().

See also

addResource()

void Nepomuk::ResourceWatcher::setTypes ( const QList< Types::Class > &  types_ )

slot

Set the types to be watched.

Every resource having one of these types will be watched for changes.

See also

addType()

bool Nepomuk::ResourceWatcher::start ( )

slot

Start the signalling of changes.

Before calling this method no signal will be emitted. In combination with stop() this allows to suspend the watching. Calling start() multiple times has no effect.

void Nepomuk::ResourceWatcher::stop ( )

slot

Stop the signalling of changes.

Allows to stop the watcher which has been started via start(). Calling stop() multiple times has no effect.

int Nepomuk::ResourceWatcher::typeCount ( ) const

slot

Return the number of types that are being watched.

This method is slightly faster than called types().count()

See also

types addType setType

QList<Types::Class> Nepomuk::ResourceWatcher::types ( ) const

slot

The types that have been configured via addType() and setTypes().

Every resource having one of these types will be watched for changes.

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The documentation for this class was generated from the following file:

• resourcewatcher.h