Package org.eclipse.persistence.queries

Class DeleteAllQuery

java.lang.Object
org.eclipse.persistence.queries.DatabaseQuery
org.eclipse.persistence.queries.ModifyQuery
org.eclipse.persistence.queries.ModifyAllQuery
org.eclipse.persistence.queries.DeleteAllQuery
All Implemented Interfaces:
Serializable, Cloneable
public class DeleteAllQuery extends ModifyAllQuery

Purpose: Query used to delete a collection of objects. This is used by mappings to delete all of their target objects in a single database call. The SQL/SQLStatements must be provided.

DeleteAll can also be used with an Expression (or JPQL) to dynamically delete a set of objects from the database, and invalidate them in the cache.

Responsibilities:

  • Stores & retrieves the objects to delete.
  • Store the where clause used for the deletion.
See Also:
Author:
Yvon Lavoie

  • Field Details

    • objects

      protected List<Object> objects
      List containing objects to be deleted, these should be removed from the identity map after deletion.

    • isInMemoryOnly

      protected boolean isInMemoryOnly
      Defines if objects should be remove from the persistence context only (no database). This is used if delete was already cascaded by the database.

  • Constructor Details

    • DeleteAllQuery

      public DeleteAllQuery()
      PUBLIC:

    • DeleteAllQuery

      public DeleteAllQuery(Class referenceClass)
      PUBLIC: Create a new delete all query for the class specified.

    • DeleteAllQuery

      public DeleteAllQuery(Class referenceClass, Expression selectionCriteria)
      PUBLIC: Create a new delete all query for the class and the selection criteria specified.

  • Method Details

    • isInMemoryOnly

      public boolean isInMemoryOnly()
      INTERNAL: Return if objects should be remove from the persistence context only (no database). This is used if delete was already cascaded by the database.

    • setIsInMemoryOnly

      public void setIsInMemoryOnly(boolean isInMemoryOnly)
      INTERNAL: Set if objects should be remove from the persistence context only (no database). This is used if delete was already cascaded by the database.

    • isDeleteAllQuery

      public boolean isDeleteAllQuery()
      PUBLIC: Return if this is a delete all query.
      Overrides:
      isDeleteAllQuery in class DatabaseQuery

    • executeInUnitOfWork

      public Object executeInUnitOfWork(org.eclipse.persistence.internal.sessions.UnitOfWorkImpl unitOfWork, org.eclipse.persistence.internal.sessions.AbstractRecord translationRow) throws DatabaseException
      INTERNAL: This method has to be broken. If commit manager is not active either an exception should be thrown (ObjectLevelModify case), or a transaction should be started early and execute on parent if remote (dataModify case). A modify query is NEVER executed on the parent, unless remote session.
      Overrides:
      executeInUnitOfWork in class ModifyAllQuery
      Parameters:
      unitOfWork - - the session in which the receiver will be executed.
      translationRow - - the arguments
      Returns:
      An object, the result of executing the query.
      Throws:
      DatabaseException - - an error has occurred on the database.

    • executeDatabaseQuery

      public Object executeDatabaseQuery() throws DatabaseException
      INTERNAL: Perform the work to delete a collection of objects. This skips the optimistic lock check and should not called for objects using locking.
      Specified by:
      executeDatabaseQuery in class DatabaseQuery
      Returns:
      Integer the number of objects (rows) deleted.
      Throws:
      DatabaseException - - an error has occurred on the database.

    • executeDeleteAll

      public void executeDeleteAll(org.eclipse.persistence.internal.sessions.AbstractSession session, org.eclipse.persistence.internal.sessions.AbstractRecord translationRow, Vector objects) throws DatabaseException
      INTERNAL: Delete all queries are executed specially to avoid cloning and ensure preparing.
      Throws:
      DatabaseException

    • getDefaultRedirector

      protected QueryRedirector getDefaultRedirector()
      INTERNAL: Returns the specific default redirector for this query type. There are numerous default query redirectors. See ClassDescriptor for their types.
      Overrides:
      getDefaultRedirector in class DatabaseQuery

    • getObjects

      public List<Object> getObjects()
      PUBLIC: Return the objects that are to be deleted

    • prepare

      protected void prepare() throws QueryException
      INTERNAL: Prepare the receiver for execution in a session.
      Overrides:
      prepare in class DatabaseQuery
      Throws:
      QueryException

    • setObjects

      public void setObjects(List<Object> objectCollection)
      PUBLIC (REQUIRED): Set the objects to be deleted. Also REQUIRED is a selection criteria or SQL string that performs the deletion of the objects. This does not generate the SQL call from the deleted objects.

      List objects used as an indicator of one of two possible ways the query may behave:

      objects != null - the "old" functionality used by OneToMany mapping objects deleted from the cache, either selection expression or custom sql should be provided for deletion from db;

      objects == null - the "new" functionality (on par with UpdateAllQuery) the cache is either left alone or in-memory query finds the cached objects to be deleted, and these objects are invalidated in cache.

      Note that empty objects is still objects != case. Signal that no cache altering is required. Used by AggregationCollectionMapping and OneToManyMapping in case they use indirection and the ValueHolder has not been instantiated.