ObjectStore (Cayenne Server 4.0.M2 API)

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 Summary

Fields
Modifier and Type	Field and Description
`protected Map<Object,org.apache.cayenne.access.ObjectDiff>`	`changes`
`protected DataContext`	`context` The DataContext that owns this ObjectStore.
`protected DataRowStore`	`dataRowCache` Stores a reference to the DataRowStore.
`protected boolean`	`dataRowCacheSet`
`protected Map<Object,Persistent>`	`objectMap`

Constructor Summary

Constructors
Constructor and Description
`ObjectStore(DataRowStore dataRowCache, Map<Object,Persistent> objectMap)` Creates an ObjectStore with `DataRowStore` and a map to use for storing registered objects.

Method Summary

Methods
Modifier and Type	Method and Description
`void`	`arcCreated(Object nodeId, Object targetNodeId, Object arcId)` Notifies implementing object that a new arc was created between two nodes.
`void`	`arcDeleted(Object nodeId, Object targetNodeId, Object arcId)` Notifies implementing object that an arc between two nodes was deleted.
`DataRow`	`getCachedSnapshot(ObjectId oid)` Returns a snapshot for ObjectId from the underlying snapshot cache.
`DataContext`	`getContext()`
`DataRowStore`	`getDataRowCache()` Returns a DataRowStore associated with this ObjectStore.
`Object`	`getNode(Object nodeId)` Returns a registered DataObject or null of no object exists for the ObjectId.
`Iterator`	`getObjectIterator()` Returns an iterator over the registered objects.
`DataRow`	`getSnapshot(ObjectId oid)` Returns a snapshot for ObjectId from the underlying snapshot cache.
`boolean`	`hasChanges()` Returns `true` if there are any modified, deleted or new objects registered with this ObjectStore, `false` otherwise.
`void`	`nodeCreated(Object nodeId)` Notifies implementing object that a new node was created in the graph.
`void`	`nodeIdChanged(Object nodeId, Object newId)` Does nothing.
`void`	`nodePropertyChanged(Object nodeId, String property, Object oldValue, Object newValue)` Records dirty object snapshot.
`void`	`nodeRemoved(Object nodeId)` Notifies implementing object that a node was removed from the graph.
`List<Persistent>`	`objectsInState(int state)` Return a subset of registered objects that are in a certain persistence state.
`void`	`objectsRolledBack()` Reverts changes to all stored uncomitted objects.
`void`	`objectsUnregistered(Collection objects)` Evicts a collection of DataObjects from the ObjectStore, invalidates the underlying cache snapshots.
`Collection<Object>`	`registeredNodes()` Returns all registered DataObjects.
`int`	`registeredObjectsCount()` Returns a number of objects currently registered with this ObjectStore.
`void`	`registerNode(Object nodeId, Object nodeObject)` "Registers" a graph node, usually storing the node in some internal map using its id as a key.
`void`	`setContext(DataContext context)`
`void`	`setDataRowCache(DataRowStore dataRowCache)` Sets parent DataRowStore.
`void`	`snapshotsChanged(SnapshotEvent event)` SnapshotEventListener implementation that processes snapshot change event, updating DataObjects that have the changes.
`Object`	`unregisterNode(Object nodeId)` "Unregisters" a graph node, forgetting any information associated with nodeId.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - objectMap
```
protected Map<Object,Persistent> objectMap
```
  - changes
```
protected Map<Object,org.apache.cayenne.access.ObjectDiff> changes
```
  - 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 Detail
  - 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 Detail
  - 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 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

Class ObjectStore

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

objectMap

changes

dataRowCache

dataRowCacheSet

context

Constructor Detail

ObjectStore

Method Detail

registeredObjectsCount

getDataRowCache

setDataRowCache

objectsUnregistered

objectsRolledBack

getCachedSnapshot

getSnapshot

getObjectIterator

hasChanges

objectsInState

snapshotsChanged

getContext

setContext

getNode

registeredNodes

registerNode

unregisterNode

nodeIdChanged

nodeCreated

nodeRemoved

nodePropertyChanged

arcCreated

arcDeleted