com.querydsl.core.group

Interface Group

All Known Implementing Classes:

GroupImpl

public interface Group

A group of rows. Group is build according to GroupDefinitions.

Author:

sasa

Method Summary

Modifier and Type	Method and Description
<T,R> R	getGroup(GroupExpression<T,R> coldef) Returns the value of the given group.
<T> java.util.List<T>	getList(Expression<T> expr) Returns a List of values in this group.
<K,V> java.util.Map<K,V>	getMap(Expression<K> key, Expression<V> value) Returns a Map of values in this group
<T> T	getOne(Expression<T> expr) Returns the value of the given single valued expression.
<T> java.util.Set<T>	getSet(Expression<T> expr) Returns a Set of values in this group.
<K,V> java.util.SortedMap<K,V>	getSortedMap(Expression<K> key, Expression<V> value) Returns a SortedMap of values in this group
<T> java.util.SortedSet<T>	getSortedSet(Expression<T> expr) Returns a SortedSet of values in this group.
java.lang.Object[]	toArray() Groups elements as an array

Method Detail

toArray

java.lang.Object[] toArray()

Groups elements as an array

Returns:

elements as an array

getGroup

<T,R> R getGroup(GroupExpression<T,R> coldef)

Returns the value of the given group.

Type Parameters:

T - Type of element in a single ResultSet row, i.e. type of Expression<T>

R - Target type of this group, e.g. List<T>

Parameters:

coldef -

Returns:

Value of given group definition in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type

getOne

<T> T getOne(Expression<T> expr)

Returns the value of the given single valued expression. This is the first value of given column within this group of the ResultSet.

Type Parameters:

T - Value type

Parameters:

expr - Grouped expression

Returns:

Value of given expression in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type (e.g. Set)

getSet

<T> java.util.Set<T> getSet(Expression<T> expr)

Returns a Set of values in this group.

Type Parameters:

T - Value type of Set

Parameters:

expr - Grouped expression

Returns:

Set of values in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type (e.g. List)

getSortedSet

<T> java.util.SortedSet<T> getSortedSet(Expression<T> expr)

Returns a SortedSet of values in this group.

Type Parameters:

T - Value type of Set

Parameters:

expr - Grouped expression

Returns:

Set of values in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type (e.g. List)

getList

<T> java.util.List<T> getList(Expression<T> expr)

Returns a List of values in this group.

Type Parameters:

T - Value type of List

Parameters:

expr - Grouped expression

Returns:

List of values in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type (e.g. Set)

getMap

<K,V> java.util.Map<K,V> getMap(Expression<K> key,
                                Expression<V> value)

Returns a Map of values in this group

Type Parameters:

K - Key type of result Map

V - Value type of result Map

Parameters:

key - Key expression

value - Value expression

Returns:

Map of values in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type (e.g. List)

getSortedMap

<K,V> java.util.SortedMap<K,V> getSortedMap(Expression<K> key,
                                            Expression<V> value)

Returns a SortedMap of values in this group

Type Parameters:

K - Key type of result Map

V - Value type of result Map

Parameters:

key - Key expression

value - Value expression

Returns:

Map of values in this group

Throws:

java.util.NoSuchElementException - if group is undefined.

java.lang.ClassCastException - if group is of different type (e.g. List)