Package org.hibernate.criterion

Class Projections

java.lang.Object

org.hibernate.criterion.Projections

public final class Projections
extends Object

The criterion package may be used by applications as a framework for building new kinds of Projection. However, it is intended that most applications will simply use the built-in projection types via the static factory methods of this class.

The factory methods that take an alias allow the projected value to be referred to by criterion and order instances.

See Also:

• Criteria
• factory methods for Criterion instances

Method Summary

Modifier and Type	Method	Description
static Projection	alias(Projection projection, String alias)	Assign an alias to a projection, by wrapping it
static AggregateProjection	avg(String propertyName)	A property average value
static CountProjection	count(String propertyName)	A property value count
static CountProjection	countDistinct(String propertyName)	A distinct property value count
static Projection	distinct(Projection proj)	Create a distinct projection from a projection
static PropertyProjection	groupProperty(String propertyName)	A grouping property value
static IdentifierProjection	id()	A projected identifier value
static AggregateProjection	max(String propertyName)	A property maximum value
static AggregateProjection	min(String propertyName)	A property minimum value
static ProjectionList	projectionList()	Create a new projection list
static PropertyProjection	property(String propertyName)	A projected property value
static Projection	rowCount()	The query row count, ie.
static Projection	sqlGroupProjection(String sql, String groupBy, String[] columnAliases, Type[] types)	A grouping SQL projection, specifying both select clause and group by clause fragments
static Projection	sqlProjection(String sql, String[] columnAliases, Type[] types)	A SQL projection, a typed select clause fragment
static AggregateProjection	sum(String propertyName)	A property value sum

Methods inherited from class java.lang.Object

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

Method Details

distinct

public static Projection distinct(Projection proj)

Create a distinct projection from a projection

projectionList

public static ProjectionList projectionList()

Create a new projection list

rowCount

public static Projection rowCount()

The query row count, ie. count(*)

count

public static CountProjection count(String propertyName)

A property value count

countDistinct

public static CountProjection countDistinct(String propertyName)

A distinct property value count

max

public static AggregateProjection max(String propertyName)

A property maximum value

min

public static AggregateProjection min(String propertyName)

A property minimum value

avg

public static AggregateProjection avg(String propertyName)

A property average value

sum

public static AggregateProjection sum(String propertyName)

A property value sum

sqlProjection

public static Projection sqlProjection(String sql,
 String[] columnAliases,
 Type[] types)

A SQL projection, a typed select clause fragment

sqlGroupProjection

public static Projection sqlGroupProjection(String sql,
 String groupBy,
 String[] columnAliases,
 Type[] types)

A grouping SQL projection, specifying both select clause and group by clause fragments

groupProperty

public static PropertyProjection groupProperty(String propertyName)

A grouping property value

property

public static PropertyProjection property(String propertyName)

A projected property value

id

public static IdentifierProjection id()

A projected identifier value

alias

public static Projection alias(Projection projection,
 String alias)

Assign an alias to a projection, by wrapping it