org.hibernate

Interface Interceptor

Known Implementing Classes:
EmptyInterceptor

public interface Interceptor

Allows user code to inspect and/or change property values.

Inspection occurs before property values are written and after they are read from the database.

There might be a single instance of Interceptor for a SessionFactory, or a new instance might be specified for each Session. Whichever approach is used, the interceptor must be serializable if the Session is to be serializable. This means that SessionFactory-scoped interceptors should implement readResolve().

The Session may not be invoked from a callback (nor may a callback cause a collection or proxy to be lazily initialized).

Instead of implementing this interface directly, it is usually better to extend EmptyInterceptor and override only the callback methods of interest.
Author:
Gavin King
See Also:
SessionFactory.openSession(Interceptor), Configuration.setInterceptor(Interceptor), EmptyInterceptor

Method Summary

void
afterTransactionBegin(Transaction tx)
Called when a Hibernate transaction is begun via the Hibernate Transaction API.
void
afterTransactionCompletion(Transaction tx)
Called after a transaction is committed or rolled back.
void
beforeTransactionCompletion(Transaction tx)
Called before a transaction is committed (but not before rollback).
int[]
findDirty(Object entity, Serializable id, Object[] currentState, Object[] previousState, String[] propertyNames, Type[] types)
Called from flush().
Object
getEntity(String entityName, Serializable id)
Get a fully loaded entity instance that is cached externally
String
getEntityName(Object object)
Get the entity name for a persistent or transient instance
Object
instantiate(String entityName, EntityMode entityMode, Serializable id)
Instantiate the entity class.
Boolean
isTransient(Object entity)
Called to distinguish between transient and detached entities.
void
onCollectionRecreate(Object collection, Serializable key)
Called before a collection is (re)created.
void
onCollectionRemove(Object collection, Serializable key)
Called before a collection is deleted.
void
onCollectionUpdate(Object collection, Serializable key)
Called before a collection is updated.
void
onDelete(Object entity, Serializable id, Object[] state, String[] propertyNames, Type[] types)
Called before an object is deleted.
boolean
onFlushDirty(Object entity, Serializable id, Object[] currentState, Object[] previousState, String[] propertyNames, Type[] types)
Called when an object is detected to be dirty, during a flush.
boolean
onLoad(Object entity, Serializable id, Object[] state, String[] propertyNames, Type[] types)
Called just before an object is initialized.
String
onPrepareStatement(String sql)
Called when sql string is being prepared.
boolean
onSave(Object entity, Serializable id, Object[] state, String[] propertyNames, Type[] types)
Called before an object is saved.
void
postFlush(Iterator entities)
Called after a flush that actually ends in execution of the SQL statements required to synchronize in-memory state with the database.
void
preFlush(Iterator entities)
Called before a flush

Method Details

afterTransactionBegin

public void afterTransactionBegin(Transaction tx)
Called when a Hibernate transaction is begun via the Hibernate Transaction API. Will not be called if transactions are being controlled via some other mechanism (CMT, for example).

afterTransactionCompletion

public void afterTransactionCompletion(Transaction tx)
Called after a transaction is committed or rolled back.

beforeTransactionCompletion

public void beforeTransactionCompletion(Transaction tx)
Called before a transaction is committed (but not before rollback).

findDirty

public int[] findDirty(Object entity,
                       Serializable id,
                       Object[] currentState,
                       Object[] previousState,
                       String[] propertyNames,
                       Type[] types)
Called from flush(). The return value determines whether the entity is updated
  • an array of property indices - the entity is dirty
  • an empty array - the entity is not dirty
  • null - use Hibernate's default dirty-checking algorithm
Parameters:
entity - a persistent entity
Returns:
array of dirty property indices or null to choose default behaviour

getEntity

public Object getEntity(String entityName,
                        Serializable id)
            throws CallbackException
Get a fully loaded entity instance that is cached externally
Parameters:
entityName - the name of the entity
id - the instance identifier
Returns:
a fully initialized entity

getEntityName

public String getEntityName(Object object)
            throws CallbackException
Get the entity name for a persistent or transient instance
Parameters:
object - an entity instance
Returns:
the name of the entity

instantiate

public Object instantiate(String entityName,
                          EntityMode entityMode,
                          Serializable id)
            throws CallbackException
Instantiate the entity class. Return null to indicate that Hibernate should use the default constructor of the class. The identifier property of the returned instance should be initialized with the given identifier.
Parameters:
entityName - the name of the entity
entityMode - The type of entity instance to be returned.
id - the identifier of the new instance
Returns:
an instance of the class, or null to choose default behaviour

isTransient

public Boolean isTransient(Object entity)
Called to distinguish between transient and detached entities. The return value determines the state of the entity with respect to the current session.
  • Boolean.TRUE - the entity is transient
  • Boolean.FALSE - the entity is detached
  • null - Hibernate uses the unsaved-value mapping and other heuristics to determine if the object is unsaved
Parameters:
entity - a transient or detached entity
Returns:
Boolean or null to choose default behaviour

onCollectionRecreate

public void onCollectionRecreate(Object collection,
                                 Serializable key)
            throws CallbackException
Called before a collection is (re)created.

onCollectionRemove

public void onCollectionRemove(Object collection,
                               Serializable key)
            throws CallbackException
Called before a collection is deleted.

onCollectionUpdate

public void onCollectionUpdate(Object collection,
                               Serializable key)
            throws CallbackException
Called before a collection is updated.

onDelete

public void onDelete(Object entity,
                     Serializable id,
                     Object[] state,
                     String[] propertyNames,
                     Type[] types)
            throws CallbackException
Called before an object is deleted. It is not recommended that the interceptor modify the state.

onFlushDirty

public boolean onFlushDirty(Object entity,
                            Serializable id,
                            Object[] currentState,
                            Object[] previousState,
                            String[] propertyNames,
                            Type[] types)
            throws CallbackException
Called when an object is detected to be dirty, during a flush. The interceptor may modify the detected currentState, which will be propagated to both the database and the persistent object. Note that not all flushes end in actual synchronization with the database, in which case the new currentState will be propagated to the object, but not necessarily (immediately) to the database. It is strongly recommended that the interceptor not modify the previousState.
Returns:
true if the user modified the currentState in any way.

onLoad

public boolean onLoad(Object entity,
                      Serializable id,
                      Object[] state,
                      String[] propertyNames,
                      Type[] types)
            throws CallbackException
Called just before an object is initialized. The interceptor may change the state, which will be propagated to the persistent object. Note that when this method is called, entity will be an empty uninitialized instance of the class.
Returns:
true if the user modified the state in any way.

onPrepareStatement

public String onPrepareStatement(String sql)
Called when sql string is being prepared.
Parameters:
sql - sql to be prepared
Returns:
original or modified sql

onSave

public boolean onSave(Object entity,
                      Serializable id,
                      Object[] state,
                      String[] propertyNames,
                      Type[] types)
            throws CallbackException
Called before an object is saved. The interceptor may modify the state, which will be used for the SQL INSERT and propagated to the persistent object.
Returns:
true if the user modified the state in any way.

postFlush

public void postFlush(Iterator entities)
            throws CallbackException
Called after a flush that actually ends in execution of the SQL statements required to synchronize in-memory state with the database.

preFlush

public void preFlush(Iterator entities)
            throws CallbackException
Called before a flush