org.datanucleus.store.rdbms.request
Class UpdateRequest

java.lang.Object
  org.datanucleus.store.rdbms.request.Request
      org.datanucleus.store.rdbms.request.UpdateRequest

public class UpdateRequest
extends Request

Class to provide a means of update of records in a data store. Extends basic request class implementing the execute method to do a JDBC update operation.

Field Summary

protected org.datanucleus.metadata.AbstractClassMetaData	cmd MetaData for the class.
protected boolean	versionChecks Whether we should make checks on optimistic version before updating.
protected org.datanucleus.metadata.VersionMetaData	versionMetaData MetaData for the version handling.

Fields inherited from class org.datanucleus.store.rdbms.request.Request

key, LOCALISER, table

Constructor Summary

UpdateRequest(org.datanucleus.store.mapped.DatastoreClass table, org.datanucleus.metadata.AbstractMemberMetaData[] reqFieldMetaData, org.datanucleus.metadata.AbstractClassMetaData cmd, org.datanucleus.ClassLoaderResolver clr)
Constructor, taking the table.

Method Summary

void	execute(org.datanucleus.store.ObjectProvider sm) Method performing the update of the record in the datastore.

Methods inherited from class java.lang.Object

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

Field Detail

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 Detail

UpdateRequest

public UpdateRequest(org.datanucleus.store.mapped.DatastoreClass table,
                     org.datanucleus.metadata.AbstractMemberMetaData[] reqFieldMetaData,
                     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. The query will be of the form

 UPDATE table-name SET param1=?,param2=? WHERE id1=? AND id2=?

or (when also performing version checks)

 UPDATE table-name SET param1=?,param2=?,version={newvers} WHERE id1=? AND id2=? AND version={oldvers}

Parameters:

table - The Class Table representing the datastore table to update

reqFieldMetaData - MetaData of the fields to update

cmd - ClassMetaData of objects being updated

clr - ClassLoader resolver

Method Detail

execute

public void execute(org.datanucleus.store.ObjectProvider sm)

Method performing the update of the record in the datastore. Takes the constructed update query and populates with the specific record information.

Specified by:

execute in class Request

Parameters:

sm - The state manager for the record to be updated