org.apache.tapestry5.hibernate
Class HibernateGridDataSource

java.lang.Object
  org.apache.tapestry5.hibernate.HibernateGridDataSource

All Implemented Interfaces:

GridDataSource

public class HibernateGridDataSource
extends Object
implements GridDataSource

A simple implementation of GridDataSource based on a Hibernate Session and a known entity class. This implementation does support multiple sort constraints; however it assumes a direct mapping from sort constraint property to Hibernate property.

This class is not thread-safe; it maintains internal state.

Typically, an instance of this object is created fresh as needed (that is, it is not stored between requests).

Constructor Summary

HibernateGridDataSource(org.hibernate.Session session, Class entityType)

Method Summary

protected void	applyAdditionalConstraints(org.hibernate.Criteria crit) Invoked after the main criteria has been set up (firstResult, maxResults and any sort contraints).
int	getAvailableRows() Returns the total number of rows for the configured entity type.
Class	getRowType() Returns the entity type, as provided via the constructor.
Object	getRowValue(int index) Returns a row value at the given index (which must be within the range defined by the call to prepare(int, int, java.util.List) ).
void	prepare(int startIndex, int endIndex, List<SortConstraint> sortConstraints) Prepares the results, performing a query (applying the sort results, and the provided start and end index).

Methods inherited from class java.lang.Object

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

Constructor Detail

HibernateGridDataSource

public HibernateGridDataSource(org.hibernate.Session session,
                               Class entityType)

Method Detail

getAvailableRows

public int getAvailableRows()

Returns the total number of rows for the configured entity type.

Specified by:

getAvailableRows in interface GridDataSource

prepare

public void prepare(int startIndex,
                    int endIndex,
                    List<SortConstraint> sortConstraints)

Prepares the results, performing a query (applying the sort results, and the provided start and end index). The results can later be obtained from getRowValue(int) }.

Specified by:

prepare in interface GridDataSource

Parameters:

startIndex - index, from zero, of the first item to be retrieved

endIndex - index, from zero, of the last item to be retrieved

sortConstraints - zero or more constraints used to set the order of the returned values

applyAdditionalConstraints

protected void applyAdditionalConstraints(org.hibernate.Criteria crit)

Invoked after the main criteria has been set up (firstResult, maxResults and any sort contraints). This gives subclasses a chance to apply additional constraints before the list of results is obtained from the criteria. This implementation does nothing and may be overridden.

getRowValue

public Object getRowValue(int index)

Returns a row value at the given index (which must be within the range defined by the call to prepare(int, int, java.util.List) ).

Specified by:

getRowValue in interface GridDataSource

Parameters:

index - of object

Returns:

object at that index

getRowType

public Class getRowType()

Returns the entity type, as provided via the constructor.

Specified by:

getRowType in interface GridDataSource

Returns:

the row type, or null