com.goldencode.p2j.persist.orm

Class AdaptiveRowStructure

java.lang.Object

com.goldencode.p2j.persist.orm.AbstractRowStructure

com.goldencode.p2j.persist.orm.AdaptiveRowStructure

All Implemented Interfaces:

RowStructure

public class AdaptiveRowStructure
extends AbstractRowStructure

Versatile row structure that can be used when there is no feedback on the order of the properties in a select query prior construction. This is an optimistic structure that presumes that the properties are in order (suitable to fast hydration). If the invariant is violated in the mean-time, this will invalidate into an un-ordered implementation.

Field Summary

Fields

Modifier and Type	Field and Description
private RowStructure	delegate The collected fields for select query

Fields inherited from class com.goldencode.p2j.persist.orm.AbstractRowStructure

dmoClass, dmoMeta, hasExtents

Constructor Summary

Constructors

Constructor and Description
AdaptiveRowStructure(DmoMeta dmoMeta) Create a new instance.

Method Summary

Modifier and Type	Method and Description
boolean	addMultiplex(Property multiplex) Append the multiplex to the row structure.
boolean	addProperty(Property prop) Append a property to the row structure.
boolean	addRecid(Property recid) Append the recid to the row structure.
int	getCount() Retrieve the number of SQL fields that will be interpreted by this row structure.
java.util.Iterator<Property>	getProps() Retrieve an iterator to all properties in this structure, including the recid and multiplex.
int	hydrate(Session session, java.sql.ResultSet resultSet, int rsOffset, BaseRecord r) The core hydration logic based on the row structure.
private void	invalidate() Invalidation logic that will pick up everything that was appended until now and moved into an un-ordered implementation.

Methods inherited from class com.goldencode.p2j.persist.orm.AbstractRowStructure

forceExtents, getDmoClass, getDmoMeta, getPropertyMeta, hasExtents, hydrateExtents, isTempTable, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.goldencode.p2j.persist.orm.RowStructure

isIncomplete

Field Detail

delegate

private RowStructure delegate

The collected fields for select query

Constructor Detail

AdaptiveRowStructure

public AdaptiveRowStructure(DmoMeta dmoMeta)

Create a new instance.

Parameters:

dmoMeta - The DMO metadata of the underlying DMO for this structure.

Method Detail

addRecid

public boolean addRecid(Property recid)

Append the recid to the row structure.

Parameters:

recid - The recid property to be appended to the structure.

Returns:

true if adding the recid to the row structure succeeded If there is some invariant on the structure, adding props may fail.

addMultiplex

public boolean addMultiplex(Property multiplex)

Append the multiplex to the row structure.

Parameters:

multiplex - The multiplex property to be appended to the structure.

Returns:

true if adding the multiplex to the row structure succeeded If there is some invariant on the structure, adding props may fail.

addProperty

public boolean addProperty(Property prop)

Append a property to the row structure. This doesn't check if the property actually belongs to the DMO class used for this structure.

Specified by:

addProperty in interface RowStructure

Overrides:

addProperty in class AbstractRowStructure

Parameters:

prop - The property to be appended to the structure.

Returns:

true if adding the prop to the row structure succeeded If there is some invariant on the structure, adding props may fail.

getCount

public int getCount()

Retrieve the number of SQL fields that will be interpreted by this row structure. This is not the same as the number of properties (e.g. datetime-tz consumes 2 SQL columns)

Returns:

The number of SQL fields that are covered by this row structure.

getProps

public java.util.Iterator<Property> getProps()

Retrieve an iterator to all properties in this structure, including the recid and multiplex.

Returns:

An iterator to all properties in this structure, in order of their append.

hydrate

public int hydrate(Session session,
                   java.sql.ResultSet resultSet,
                   int rsOffset,
                   BaseRecord r)
            throws PersistenceException,
                   java.sql.SQLException

The core hydration logic based on the row structure. This class is specialized in traversing the result-set and populating the record with the data found there.

Parameters:

session - The underlying session that generated the result-set. It is used only to emit load SQLs for the non-expanded extents. If this is null, the normalized extents will be skipped.

resultSet - The result-set that provides the low-level data that should be hydrated into the record.

rsOffset - The offset where the DMO starts. This is the case for queries that had joins, so the current record may not start at index 1.

r - The record to be hydrated.

Returns:

The next rsOffset, from where the next DMO in the result-set will start (if any).

Throws:

PersistenceException - thrown when hydrating extents fails (as it requires extra SQL queries to be run).

java.sql.SQLException - throw when failing to hydrate from the result-set.

invalidate

private void invalidate()

Invalidation logic that will pick up everything that was appended until now and moved into an un-ordered implementation. This routine should be avoided as much as possible in the critical parts, as it is quite time consuming.