Class ObjectStore

java.lang.Object
org.apache.cayenne.access.ObjectStore
All Implemented Interfaces:
Serializable, EventListener, SnapshotEventListener, GraphChangeHandler, GraphManager
Direct Known Subclasses:
NoSyncObjectStore

public class ObjectStore
extends Object
implements Serializable, SnapshotEventListener, GraphManager
ObjectStore stores objects using their ObjectId as a key. It works as a dedicated object cache for a DataContext. Users rarely need to access ObjectStore directly, as DataContext serves as a facade, providing cover methods for most ObjectStore operations.
Since:
1.0
See Also:
Serialized Form
  • Field Details

    • objectMap

      protected Map<Object,​Persistent> objectMap
    • changes

      protected Map<Object,​org.apache.cayenne.access.ObjectDiff> changes
    • trackedFlattenedPaths

      protected Map<Object,​Set<String>> trackedFlattenedPaths
      Map that tracks flattened paths for given object Id that is present in db. Presence of path in this map is used to separate insert from update case of flattened records.
      Since:
      4.1
    • dataRowCache

      protected transient DataRowStore dataRowCache
      Stores a reference to the DataRowStore.

      Serialization note: It is up to the owner of this ObjectStore to initialize DataRowStore after deserialization of this object. ObjectStore will not know how to restore the DataRowStore by itself.

    • dataRowCacheSet

      protected boolean dataRowCacheSet
    • context

      protected DataContext context
      The DataContext that owns this ObjectStore.
  • Constructor Details

    • ObjectStore

      public ObjectStore​(DataRowStore dataRowCache, Map<Object,​Persistent> objectMap)
      Creates an ObjectStore with DataRowStore and a map to use for storing registered objects. Passed map doesn't require any special synchronization behavior, as ObjectStore is synchronized itself.
      Since:
      3.0
  • Method Details

    • registeredObjectsCount

      public int registeredObjectsCount()
      Returns a number of objects currently registered with this ObjectStore.
      Since:
      1.2
    • getDataRowCache

      public DataRowStore getDataRowCache()
      Returns a DataRowStore associated with this ObjectStore.
    • setDataRowCache

      public void setDataRowCache​(DataRowStore dataRowCache)
      Sets parent DataRowStore. Registers to receive SnapshotEvents if the cache is configured to allow ObjectStores to receive such events.
    • objectsUnregistered

      public void objectsUnregistered​(Collection objects)
      Evicts a collection of DataObjects from the ObjectStore, invalidates the underlying cache snapshots. Changes objects state to TRANSIENT. This method can be used for manual cleanup of Cayenne cache.
    • objectsRolledBack

      public void objectsRolledBack()
      Reverts changes to all stored uncomitted objects.
      Since:
      1.1
    • getCachedSnapshot

      public DataRow getCachedSnapshot​(ObjectId oid)
      Returns a snapshot for ObjectId from the underlying snapshot cache. If cache contains no snapshot, a null is returned.
      Since:
      1.1
    • getSnapshot

      public DataRow getSnapshot​(ObjectId oid)
      Returns a snapshot for ObjectId from the underlying snapshot cache. If cache contains no snapshot, it will attempt fetching it using provided QueryEngine. If fetch attempt fails or inconsistent data is returned, underlying cache will throw a CayenneRuntimeException.
      Since:
      1.2
    • getObjectIterator

      public Iterator<Persistent> getObjectIterator()
      Returns an iterator over the registered objects.
    • hasChanges

      public boolean hasChanges()
      Returns true if there are any modified, deleted or new objects registered with this ObjectStore, false otherwise. This method will treat "phantom" modifications are real ones. I.e. if you "change" an object property to an equivalent value, this method will still think such object is modified. Phantom modifications are only detected and discarded during commit.
    • objectsInState

      public List<Persistent> objectsInState​(int state)
      Return a subset of registered objects that are in a certain persistence state. Collection is returned by copy.
    • snapshotsChanged

      public void snapshotsChanged​(SnapshotEvent event)
      SnapshotEventListener implementation that processes snapshot change event, updating DataObjects that have the changes.

      Implementation note: This method should not attempt to alter the underlying DataRowStore, since it is normally invoked *AFTER* the DataRowStore was modified as a result of some external interaction.

      Specified by:
      snapshotsChanged in interface SnapshotEventListener
      Since:
      1.1
    • getContext

      public DataContext getContext()
      Since:
      1.2
    • setContext

      public void setContext​(DataContext context)
      Since:
      1.2
    • getNode

      public Object getNode​(Object nodeId)
      Returns a registered DataObject or null of no object exists for the ObjectId.
      Specified by:
      getNode in interface GraphManager
      Since:
      1.2
    • registeredNodes

      public Collection<Object> registeredNodes()
      Returns all registered DataObjects. List is returned by copy and can be modified by the caller.
      Specified by:
      registeredNodes in interface GraphManager
      Since:
      1.2
    • registerNode

      public void registerNode​(Object nodeId, Object nodeObject)
      Description copied from interface: GraphManager
      "Registers" a graph node, usually storing the node in some internal map using its id as a key.
      Specified by:
      registerNode in interface GraphManager
      Since:
      1.2
    • unregisterNode

      public Object unregisterNode​(Object nodeId)
      Description copied from interface: GraphManager
      "Unregisters" a graph node, forgetting any information associated with nodeId.
      Specified by:
      unregisterNode in interface GraphManager
      Since:
      1.2
    • nodeIdChanged

      public void nodeIdChanged​(Object nodeId, Object newId)
      Does nothing.
      Specified by:
      nodeIdChanged in interface GraphChangeHandler
      Since:
      1.2
    • nodeCreated

      public void nodeCreated​(Object nodeId)
      Description copied from interface: GraphChangeHandler
      Notifies implementing object that a new node was created in the graph.
      Specified by:
      nodeCreated in interface GraphChangeHandler
      Since:
      1.2
    • nodeRemoved

      public void nodeRemoved​(Object nodeId)
      Description copied from interface: GraphChangeHandler
      Notifies implementing object that a node was removed from the graph.
      Specified by:
      nodeRemoved in interface GraphChangeHandler
      Since:
      1.2
    • nodePropertyChanged

      public void nodePropertyChanged​(Object nodeId, String property, Object oldValue, Object newValue)
      Records dirty object snapshot.
      Specified by:
      nodePropertyChanged in interface GraphChangeHandler
      Since:
      1.2
    • arcCreated

      public void arcCreated​(Object nodeId, Object targetNodeId, Object arcId)
      Description copied from interface: GraphChangeHandler
      Notifies implementing object that a new arc was created between two nodes.
      Specified by:
      arcCreated in interface GraphChangeHandler
      Since:
      1.2
    • arcDeleted

      public void arcDeleted​(Object nodeId, Object targetNodeId, Object arcId)
      Description copied from interface: GraphChangeHandler
      Notifies implementing object that an arc between two nodes was deleted.
      Specified by:
      arcDeleted in interface GraphChangeHandler
      Since:
      1.2