org.apache.openjpa.kernel
Class DelegatingStoreManager

java.lang.Object
  org.apache.openjpa.kernel.DelegatingStoreManager

All Implemented Interfaces:

StoreManager, Closeable

Direct Known Subclasses:

DataCacheStoreManager

public abstract class DelegatingStoreManager
extends Object
implements StoreManager

Base class for store manager decorators that delegate to another store manager for some operations.

Author:

Abe White

Field Summary

Fields inherited from interface org.apache.openjpa.kernel.StoreManager

FORCE_LOAD_ALL, FORCE_LOAD_DFG, FORCE_LOAD_NONE, FORCE_LOAD_REFRESH, VERSION_DIFFERENT, VERSION_EARLIER, VERSION_LATER, VERSION_SAME

Constructor Summary

DelegatingStoreManager(StoreManager store)
Constructor.

Method Summary

boolean	assignField(OpenJPAStateManager sm, int field, boolean preFlush) Assign a value to the given field.
boolean	assignObjectId(OpenJPAStateManager sm, boolean preFlush) Assign an object id to the given new instance.
void	beforeStateChange(OpenJPAStateManager sm, PCState fromState, PCState toState) Notification that the given state manager is about to change its lifecycle state.
void	begin() Begin a data store transaction.
void	beginOptimistic() Notification that an optimistic transaction has started.
boolean	cancelAll() Cancel all pending data store statements.
void	close() Free any resources this store manager is using.
void	commit() Commit the current data store transaction.
int	compareVersion(OpenJPAStateManager state, Object v1, Object v2) Compare the two version objects.
Object	copyDataStoreId(Object oid, ClassMetaData meta) Copy the given object id value.
boolean	equals(Object other)
ResultObjectProvider	executeExtent(ClassMetaData meta, boolean subclasses, FetchConfiguration fetch) Return a provider for all instances of the given candidate class, optionally including subclasses.
boolean	exists(OpenJPAStateManager sm, Object context) Verify that the given instance exists in the data store; return false if it does not.
Collection	flush(Collection sms) Flush the given state manager collection to the datastore, returning a collection of exceptions encountered during flushing.
Object	getClientConnection() Return a connection to the data store suitable for client use.
Seq	getDataStoreIdSequence(ClassMetaData forClass) Return a sequence that generates datastore identity values for the given class.
Class	getDataStoreIdType(ClassMetaData meta) Return the class used by this StoreManager for datastore identity values.
StoreManager	getDelegate() Return the wrapped store manager.
StoreManager	getInnermostDelegate() Return the base underlying native store manager.
Class	getManagedType(Object oid) Return the persistent class for the given data store identity value.
Seq	getValueSequence(FieldMetaData fmd) Return a sequence that generates values for the given field.
int	hashCode()
boolean	initialize(OpenJPAStateManager sm, PCState state, FetchConfiguration fetch, Object context) Initialize the given state manager.
boolean	load(OpenJPAStateManager sm, BitSet fields, FetchConfiguration fetch, int lockLevel, Object context) Load the given state manager.
Collection	loadAll(Collection sms, PCState state, int load, FetchConfiguration fetch, Object context) Initialize, load, or validate the existance of all of the given objects.
Object	newDataStoreId(Object oidVal, ClassMetaData meta) Create a new unique datastore identity for the given type from the given oid value (presumably pk, stringified oid, or oid instance).
FetchConfiguration	newFetchConfiguration() Return a fetch configuration suitable for this runtime.
StoreQuery	newQuery(String language) Return a query implementation suitable for this store.
void	releaseConnection() Instruct the store to release a retained connection.
void	retainConnection() Instruct the store to retain a connection for continued use.
void	rollback() Rollback the current data store transaction.
void	rollbackOptimistic() Notification that an optimistic transaction was rolled back before a data store transaction ever began.
void	setContext(StoreContext ctx) Set a reference to the corresponding context.
boolean	syncVersion(OpenJPAStateManager sm, Object context) Update the version information in the given state manager to the version stored in the data store.

Methods inherited from class java.lang.Object

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

Constructor Detail

DelegatingStoreManager

public DelegatingStoreManager(StoreManager store)

Constructor. Supply delegate.

Method Detail

getDelegate

public StoreManager getDelegate()

Return the wrapped store manager.

getInnermostDelegate

public StoreManager getInnermostDelegate()

Return the base underlying native store manager.

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object other)

Overrides:

equals in class Object

setContext

public void setContext(StoreContext ctx)

Description copied from interface: StoreManager

Set a reference to the corresponding context. This method will be called before the store manager is used. The store manager is responsible for pulling any necessary configuration data from the context, including the transaction mode and connection retain mode.

Specified by:

setContext in interface StoreManager

beginOptimistic

public void beginOptimistic()

Description copied from interface: StoreManager

Notification that an optimistic transaction has started. This method does not replace the StoreManager.begin() method, which will still be called when a true data store transaction should begin.

Specified by:

beginOptimistic in interface StoreManager

rollbackOptimistic

public void rollbackOptimistic()

Description copied from interface: StoreManager

Notification that an optimistic transaction was rolled back before a data store transaction ever began.

Specified by:

rollbackOptimistic in interface StoreManager

begin

public void begin()

Description copied from interface: StoreManager

Begin a data store transaction. After this method is called, it is assumed that all further operations are operating in a single transaction that can be committed or rolled back. If optimistic transactions are in use, this method will only be called when the system requires a transactionally consistent connection due to a user request to flush or commit the transaction. In this case, it is possible that the optimistic transaction does not have the latest versions of all instances (i.e. another transaction has modified the same instances and committed since the optimistic transaction started). On commit, an exception must be thrown on any attempt to overwrite data for an instance with an older version.

Specified by:

begin in interface StoreManager

commit

public void commit()

Description copied from interface: StoreManager

Commit the current data store transaction.

Specified by:

commit in interface StoreManager

rollback

public void rollback()

Description copied from interface: StoreManager

Rollback the current data store transaction.

Specified by:

rollback in interface StoreManager

exists

public boolean exists(OpenJPAStateManager sm,
                      Object context)

Description copied from interface: StoreManager

Verify that the given instance exists in the data store; return false if it does not.

Specified by:

exists in interface StoreManager

syncVersion

public boolean syncVersion(OpenJPAStateManager sm,
                           Object context)

Description copied from interface: StoreManager

Update the version information in the given state manager to the version stored in the data store.

Specified by:

syncVersion in interface StoreManager

Parameters:

sm - the instance to check

context - the current execution data, or null if not given to the calling method of the context

Returns:

true if the instance still exists in the datastore and is up-to-date, false otherwise

initialize

public boolean initialize(OpenJPAStateManager sm,
                          PCState state,
                          FetchConfiguration fetch,
                          Object context)

Description copied from interface: StoreManager

Initialize the given state manager. The object id of the state manager will be set, and the state manager's metadata be set to the class of the instance to load, or possibly one of its superclasses. Initialization involves first calling the OpenJPAStateManager.initialize(java.lang.Class, org.apache.openjpa.kernel.PCState) method with a new instance of the correct type constructed with the PCRegistry.newInstance(Class, org.apache.openjpa.enhance.StateManager, boolean) method (this will reset the state manager's metadata if the actual type was a subclass). After instance initialization, load any the fields for the given fetch configuration that can be efficiently retrieved. If any of the configured fields are not loaded in this method, they will be loaded with a subsequent call to StoreManager.load(org.apache.openjpa.kernel.OpenJPAStateManager, java.util.BitSet, org.apache.openjpa.kernel.FetchConfiguration, int, java.lang.Object). If this method is called during a data store transaction, the instance's database record should be locked. Version information can be loaded if desired through the OpenJPAStateManager.setVersion(java.lang.Object) method.

Specified by:

initialize in interface StoreManager

Parameters:

sm - the instance to initialize

state - the lifecycle state to initialize the state manager with

fetch - configuration for how to load the instance

context - the current execution data, or null if not given to the calling method of the broker

Returns:

true if the matching instance exists in the data store, false otherwise

load

public boolean load(OpenJPAStateManager sm,
                    BitSet fields,
                    FetchConfiguration fetch,
                    int lockLevel,
                    Object context)

Description copied from interface: StoreManager

Load the given state manager. Note that any collection or map types loaded into the state manager will be proxied with the correct type; therefore the store manager does not have to load the same concrete collection/map types as the instance declares. However, array types must be consistent with the array type stored by the persistence capable instance. If this method is called during a data store transaction, the instance should be locked. If the given state manager does not have its version set already, version information can be loaded if desired through the OpenJPAStateManager.setVersion(java.lang.Object) method.

Specified by:

load in interface StoreManager

Parameters:

sm - the instance to load

fields - set of fields to load; all field indexes in this set must be loaded; this set is mutable

fetch - the fetch configuration to use when loading related objects

lockLevel - attempt to load simple fields at this lock level; relations should be loaded at the read lock level of the fetch configuration

context - the current execution data, or null if not given to the calling method of the broker

Returns:

false if the object no longer exists in the database, true otherwise

loadAll

public Collection loadAll(Collection sms,
                          PCState state,
                          int load,
                          FetchConfiguration fetch,
                          Object context)

Description copied from interface: StoreManager

Initialize, load, or validate the existance of all of the given objects. This method is called from various broker methods that act on multiple objects, such as StoreContext.retrieveAll(java.util.Collection, boolean, org.apache.openjpa.kernel.OpCallbacks). It gives the store manager an opportunity to efficiently batch-load data for several objects. Each of the given state managers will be in one of three states, each requiring a different action:

• stateManager.getO () == null: An uninitialized state manager. Perform the same actions as in StoreManager.initialize(org.apache.openjpa.kernel.OpenJPAStateManager, org.apache.openjpa.kernel.PCState, org.apache.openjpa.kernel.FetchConfiguration, java.lang.Object).
• load != FORCE_LOAD_NONE || stateManager.getPCState () == PCState.HOLLOW: A hollow state manager, or one whose fields must be loaded because this is a refresh or retrieve action. Peform the same actions as in StoreManager.load(org.apache.openjpa.kernel.OpenJPAStateManager, java.util.BitSet, org.apache.openjpa.kernel.FetchConfiguration, int, java.lang.Object), choosing the fields to load based on the fetch configuration, or loading all fields if load == FORCE_LOAD_ALL. Any required fields left unloaded will cause a subsequent invocation of StoreManager.load(org.apache.openjpa.kernel.OpenJPAStateManager, java.util.BitSet, org.apache.openjpa.kernel.FetchConfiguration, int, java.lang.Object) on the individual object in question.
• load == FORCE_LOAD_NONE && stateManager.getPCState () != PCState.HOLLOW: A non-hollow state manager. Perform the same actions as in StoreManager.exists(org.apache.openjpa.kernel.OpenJPAStateManager, java.lang.Object), and load additional state if desired. Non-hollow objects will only be included outside of refresh invocations if a user calls findAll with the validate parameter set to true.

Store managers that cannot efficiently batch load can simply test for these conditions and delegate to the proper methods.

Specified by:

loadAll in interface StoreManager

Parameters:

sms - the state manager instances to load

state - the lifecycle state to initialize uninitialized state managers with; may be null if no uninitialized instances are included in sms

load - one of the FORCE_LOAD_* constants describing the fields to force-load if this is a refresh or retrieve action

fetch - the current fetch configuration to use when loading related objects

context - the current execution data, or null if not given to the calling method of the broker

Returns:

a collection of the state manager identities for which no data store record exists

See Also:

ImplHelper.loadAll(java.util.Collection, org.apache.openjpa.kernel.StoreManager, org.apache.openjpa.kernel.PCState, int, org.apache.openjpa.kernel.FetchConfiguration, java.lang.Object)

beforeStateChange

public void beforeStateChange(OpenJPAStateManager sm,
                              PCState fromState,
                              PCState toState)

Description copied from interface: StoreManager

Notification that the given state manager is about to change its lifecycle state. The store manager is not required to do anything in this method, but some back ends may need to.

Specified by:

beforeStateChange in interface StoreManager

flush

public Collection flush(Collection sms)

Description copied from interface: StoreManager

Flush the given state manager collection to the datastore, returning a collection of exceptions encountered during flushing. The given collection may include states that do not require data store action, such as persistent-clean instances or persistent-dirty instances that have not been modified since they were last flushed. For datastore updates and inserts, the dirty, non-flushed fields of each state should be flushed. New instances without an assigned object id should be given one via OpenJPAStateManager.setObjectId(java.lang.Object). New instances with value-strategy fields that have not been assigned yet should have their fields set. Datastore version information should be updated during flush, and the state manager's version indicator updated through the OpenJPAStateManager.setNextVersion(java.lang.Object) method. The current version will roll over to this next version upon successful commit.

Specified by:

flush in interface StoreManager

See Also:

org.apache.openjpa.util.ApplicationIds#assign()

assignObjectId

public boolean assignObjectId(OpenJPAStateManager sm,
                              boolean preFlush)

Description copied from interface: StoreManager

Assign an object id to the given new instance. Return false if the instance cannot be assigned an identity because a flush is required (for example, the identity is determined by the datastore on insert). For application identity instances, the assigned object id should be based on field state. The implementation is responsible for using the proper value strategy according to the instance metadata. This method is called the first time a user requests the oid of a new instance before flush.

Specified by:

assignObjectId in interface StoreManager

preFlush - whether this assignment is being requested by the system as part of pre-flush activities, and can be ignored if it is more efficient to assign within StoreManager.flush(java.util.Collection)

See Also:

ImplHelper.generateFieldValue(org.apache.openjpa.kernel.StoreContext, org.apache.openjpa.meta.FieldMetaData), ImplHelper.generateIdentityValue(org.apache.openjpa.kernel.StoreContext, org.apache.openjpa.meta.ClassMetaData, int), org.apache.openjpa.util.ApplicationIds#assign()

assignField

public boolean assignField(OpenJPAStateManager sm,
                           int field,
                           boolean preFlush)

Description copied from interface: StoreManager

Assign a value to the given field. Return false if the value cannot be assigned because a flush is required (for example, the field value is determined by the datastore on insert). This method is called the first time a user requests the value of a field with a value-strategy on a new instance before flush.

Specified by:

assignField in interface StoreManager

preFlush - whether this assignment is being requested by the system as part of pre-flush activities, and can be ignored if it is more efficient to assign within StoreManager.flush(java.util.Collection)

See Also:

ImplHelper.generateFieldValue(org.apache.openjpa.kernel.StoreContext, org.apache.openjpa.meta.FieldMetaData)

getManagedType

public Class getManagedType(Object oid)

Description copied from interface: StoreManager

Return the persistent class for the given data store identity value. If the given value is not a datastore identity object, return null.

Specified by:

getManagedType in interface StoreManager

getDataStoreIdType

public Class getDataStoreIdType(ClassMetaData meta)

Description copied from interface: StoreManager

Return the class used by this StoreManager for datastore identity values. The given metadata may be null, in which case the return value should the common datastore identity class for all classes, or null if this store manager does not use a common identity class.

Specified by:

getDataStoreIdType in interface StoreManager

copyDataStoreId

public Object copyDataStoreId(Object oid,
                              ClassMetaData meta)

Description copied from interface: StoreManager

Copy the given object id value. Use the described type of the given metadata, which may be a subclass of the given oid's described type.

Specified by:

copyDataStoreId in interface StoreManager

newDataStoreId

public Object newDataStoreId(Object oidVal,
                             ClassMetaData meta)

Description copied from interface: StoreManager

Create a new unique datastore identity for the given type from the given oid value (presumably pk, stringified oid, or oid instance).

Specified by:

newDataStoreId in interface StoreManager

getClientConnection

public Object getClientConnection()

Description copied from interface: StoreManager

Return a connection to the data store suitable for client use. If this method is called during a data store transaction, thie connection must be transactional. If no connection is in use, this method should create one to return.

Specified by:

getClientConnection in interface StoreManager

retainConnection

public void retainConnection()

Description copied from interface: StoreManager

Instruct the store to retain a connection for continued use. This will be invoked automatically based on the user's configured connection retain mode.

Specified by:

retainConnection in interface StoreManager

releaseConnection

public void releaseConnection()

Description copied from interface: StoreManager

Instruct the store to release a retained connection. This will be invoked automatically based on the user's configured connection retain mode.

Specified by:

releaseConnection in interface StoreManager

executeExtent

public ResultObjectProvider executeExtent(ClassMetaData meta,
                                          boolean subclasses,
                                          FetchConfiguration fetch)

Description copied from interface: StoreManager

Return a provider for all instances of the given candidate class, optionally including subclasses. The given candidate may be an unmapped type with mapped subclasses. If the provider is iterated within a data store transaction, returned instances should be locked.

Specified by:

executeExtent in interface StoreManager

newQuery

public StoreQuery newQuery(String language)

Description copied from interface: StoreManager

Return a query implementation suitable for this store. If the query is iterated within a data store transaction, returned instances should be locked. Return null if this store does not support native execution of the given language. OpenJPA can execute JPQL in memory even without back end support.

Specified by:

newQuery in interface StoreManager

Parameters:

language - the query language

newFetchConfiguration

public FetchConfiguration newFetchConfiguration()

Description copied from interface: StoreManager

Return a fetch configuration suitable for this runtime. Typically will be or extend FetchConfigurationImpl.

Specified by:

newFetchConfiguration in interface StoreManager

close

public void close()

Description copied from interface: StoreManager

Free any resources this store manager is using.

Specified by:

close in interface StoreManager

Specified by:

close in interface Closeable

compareVersion

public int compareVersion(OpenJPAStateManager state,
                          Object v1,
                          Object v2)

Description copied from interface: StoreManager

Compare the two version objects.

Specified by:

compareVersion in interface StoreManager

Parameters:

state - the state manager for the object

v1 - the first version object to compare

v2 - the second version object to compare

Returns:

• StoreManager.VERSION_LATER if v1 is later than v2
• StoreManager.VERSION_EARLIER if v1 is earlier than v2
• StoreManager.VERSION_SAME if v1 is the same as v2
• StoreManager.VERSION_DIFFERENT if v1 is different from v2, but the time difference of the versions cannot be determined

getDataStoreIdSequence

public Seq getDataStoreIdSequence(ClassMetaData forClass)

Description copied from interface: StoreManager

Return a sequence that generates datastore identity values for the given class. This method will only be called when the identity strategy for the class is one of:

• ValueStrategies.NATIVE
• ValueStrategies.AUTOASSIGN
• ValueStrategies.INCREMENT

If the identity strategy cannot be represented as a sequence, return null.

Specified by:

getDataStoreIdSequence in interface StoreManager

getValueSequence

public Seq getValueSequence(FieldMetaData fmd)

Description copied from interface: StoreManager

Return a sequence that generates values for the given field. This method will only be called when the value strategy for the field is one of:

• ValueStrategies.NATIVE
• ValueStrategies.AUTOASSIGN
• ValueStrategies.INCREMENT

If the value strategy cannot be represented as a sequence, return null.

Specified by:

getValueSequence in interface StoreManager

cancelAll

public boolean cancelAll()

Description copied from interface: StoreManager

Cancel all pending data store statements.

Specified by:

cancelAll in interface StoreManager

Returns:

true if any statements cancelled, false otherwise