Class DeleteRequest

java.lang.Object

org.datanucleus.store.rdbms.request.Request

org.datanucleus.store.rdbms.request.DeleteRequest

public class DeleteRequest
extends Request

Class to provide a means of deletion of records from an RDBMS. Extends basic request class implementing the execute method to do a JDBC delete operation. Provides a version check for optimistic handling. The SQL will be of the form

DELETE FROM TBL_NAME WHERE id1=? AND id2=?

or, if "soft delete" is being used for this type, then

UPDATE TBL_NAME SET DELETE_COL=TRUE WHERE id1=? AND id2=?

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private class	DeleteRequest.DeleteMappingConsumer	Mapping Consumer used for generating the DELETE statement for an object in a table.

Field Summary

Fields

Modifier and Type	Field	Description
protected org.datanucleus.metadata.AbstractClassMetaData	cmd	MetaData for the class.
private final String	deleteStmt	Statement for deleting the object from the datastore.
private final String	deleteStmtOptimistic	Statement for deleting the object from the datastore (optimistic txns).
private final List<MappingCallbacks>	mappingCallbacks
private StatementMappingDefinition	mappingStatementIndex	the index for the expression(s) in the delete statement.
private StatementMappingIndex	multitenancyStatementMapping	StatementExpressionIndex for multitenancy.
private final org.datanucleus.metadata.AbstractMemberMetaData[]	oneToOneNonOwnerFields	1-1 bidir non-owner fields that are reachable (but not updated) and have no datastore column.
private final String	softDeleteStmt	Statement for soft-deleting the object from the datastore.
protected boolean	versionChecks	Whether we should make checks on optimistic version before updating.
protected org.datanucleus.metadata.VersionMetaData	versionMetaData	MetaData for the version handling.
private final int[]	whereFieldNumbers	PK fields to be provided in defining the record to be deleted (app identity cases).

Fields inherited from class Request

key, table

Constructor Summary

Constructors

Constructor	Description
DeleteRequest(DatastoreClass table, org.datanucleus.metadata.AbstractClassMetaData cmd, org.datanucleus.ClassLoaderResolver clr)	Constructor, taking the table.

Method Summary

Modifier and Type	Method	Description
void	execute(org.datanucleus.state.DNStateManager sm)	Method performing the deletion of the record from the datastore.
private void	updateOneToOneBidirectionalOwnerObjectForField(org.datanucleus.state.DNStateManager sm, org.datanucleus.metadata.AbstractMemberMetaData mmd)	Method to update any 1-1 bidir non-owner fields where the foreign-key is stored in the other object.

Methods inherited from class Object

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

Field Details

mappingCallbacks

private final List<MappingCallbacks> mappingCallbacks

deleteStmt

private final String deleteStmt

Statement for deleting the object from the datastore.

deleteStmtOptimistic

private final String deleteStmtOptimistic

Statement for deleting the object from the datastore (optimistic txns).

softDeleteStmt

private final String softDeleteStmt

Statement for soft-deleting the object from the datastore.

mappingStatementIndex

private StatementMappingDefinition mappingStatementIndex

the index for the expression(s) in the delete statement.

multitenancyStatementMapping

private StatementMappingIndex multitenancyStatementMapping

StatementExpressionIndex for multitenancy.

whereFieldNumbers

private final int[] whereFieldNumbers

PK fields to be provided in defining the record to be deleted (app identity cases).

oneToOneNonOwnerFields

private final org.datanucleus.metadata.AbstractMemberMetaData[] oneToOneNonOwnerFields

1-1 bidir non-owner fields that are reachable (but not updated) and have no datastore column.

cmd

protected org.datanucleus.metadata.AbstractClassMetaData cmd

MetaData for the class.

versionMetaData

protected org.datanucleus.metadata.VersionMetaData versionMetaData

MetaData for the version handling.

versionChecks

protected boolean versionChecks

Whether we should make checks on optimistic version before updating.

Constructor Details

DeleteRequest

public DeleteRequest(DatastoreClass table,
 org.datanucleus.metadata.AbstractClassMetaData cmd,
 org.datanucleus.ClassLoaderResolver clr)

Constructor, taking the table. Uses the structure of the datastore table to build a basic query.

Parameters:

table - The Class Table representing the datastore table to delete.

cmd - ClassMetaData of objects being deleted

clr - ClassLoader resolver

Method Details

execute

public void execute(org.datanucleus.state.DNStateManager sm)

Method performing the deletion of the record from the datastore. Takes the constructed deletion query and populates with the specific record information.

Specified by:

execute in class Request

Parameters:

sm - StateManager for the record to be deleted.

updateOneToOneBidirectionalOwnerObjectForField

private void updateOneToOneBidirectionalOwnerObjectForField(org.datanucleus.state.DNStateManager sm,
 org.datanucleus.metadata.AbstractMemberMetaData mmd)

Method to update any 1-1 bidir non-owner fields where the foreign-key is stored in the other object.

Parameters:

sm - StateManager of this object

mmd - MetaData for field that has related (owner) objects