Projections (Red Hat JBoss Enterprise Application Platform 6.4.19.GA public API)

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.

Author:

Gavin King

See Also:
Criteria, factory methods for Criterion instances

Method Summary

Methods
Modifier and Type	Method and 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 Detail

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

Class Projections