org.jpox.store.rdbms.request
Class FetchRequest

java.lang.Object
  org.jpox.store.rdbms.request.Request
      org.jpox.store.rdbms.request.FetchRequest

public class FetchRequest
extends Request

Class to retrieve a series of fields for an object of a class from the datastore. All fields are retrieved in a single SELECT, selecting a candidate table (the most derived table for which a field is required), and INNER JOINs to all superclass tables that are also required.

Any surrogate version stored in this table will be fetched *if* the object being updated doesnt already have a value for it. If the caller wants the surrogate version to be updated then they should nullify the "transactional" version before calling.

Version:

$Revision: 1.85 $

Field Summary

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

key, LOCALISER, table

Constructor Summary

FetchRequest(org.jpox.store.mapped.DatastoreClass classTable, org.jpox.metadata.AbstractMemberMetaData[] fieldMetaData, java.lang.Class cls, org.jpox.ClassLoaderResolver clr)
Constructor, taking the table.

Method Summary

void	execute(org.jpox.StateManager sm) Method performing the retrieval of the record from the datastore.

Methods inherited from class java.lang.Object

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

Constructor Detail

FetchRequest

public FetchRequest(org.jpox.store.mapped.DatastoreClass classTable,
                    org.jpox.metadata.AbstractMemberMetaData[] fieldMetaData,
                    java.lang.Class cls,
                    org.jpox.ClassLoaderResolver clr)

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

Parameters:

classTable - The Class Table representing the datastore table to retrieve

fieldMetaData - MetaData of the fields to retrieve

cls - Class of objects being fetched

clr - ClassLoader resolver

Method Detail

execute

public void execute(org.jpox.StateManager sm)

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

Specified by:

execute in class Request

Parameters:

sm - The state manager for the record to be retrieved