net.sf.mmm.util.query.base

Class ListQueryImpl<E,T>

java.lang.Object

net.sf.mmm.util.query.base.QueryImpl<List<E>,E,T>

net.sf.mmm.util.query.base.ListQueryImpl<E,T>

Type Parameters:

E - the generic type of the List-elements.

T - the generic type of the internal results.

All Implemented Interfaces:

Iterable<E>, Command, ListQuery<E>, Query<List<E>>

public class ListQueryImpl<E,T>
extends QueryImpl<List<E>,E,T>
implements ListQuery<E>

This is the implementation of ListQuery.

Since:

8.0.0

Author:

hohwille

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
(package private) static class	ListQueryImpl.IteratorAdapter<E,T>

Field Summary

Fields

Modifier and Type	Field and Description
private Function<T,E>	mapper

Constructor Summary

Constructors

Constructor and Description
ListQueryImpl(AbstractSelectStatement<E,?,T> statement, String sql, QueryMode mode, Function<T,E> mapper) The constructor.

Method Summary

Modifier and Type	Method and Description
List<E>	execute() Executes the Query Command and returns the result.
protected Function<T,E>	getMapper()
Iterator<E>	iterator() Executes the query and returns the matching objects as Iterator.
private Iterator<T>	iteratorInternal()

Methods inherited from class net.sf.mmm.util.query.base.QueryImpl

executeInternal, getMode, getSql, getStatement, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface net.sf.mmm.util.query.api.Command

getSql

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

mapper

private final Function<T,E> mapper

Constructor Detail

ListQueryImpl

public ListQueryImpl(AbstractSelectStatement<E,?,T> statement,
                     String sql,
                     QueryMode mode,
                     Function<T,E> mapper)

The constructor.

Parameters:

statement - the AbstractSelectStatement that created this Query.

sql - the SQL of the statement.

mode - the QueryMode.

mapper - the Function to map the results.

Method Detail

getMapper

protected Function<T,E> getMapper()

Returns:

the Function to map the original query results to the external result type. May be null for the identity function if <T>=<E>.

execute

public List<E> execute()

Description copied from interface: Query

Executes the Query Command and returns the result.

Specified by:

execute in interface Query<List<E>>

Overrides:

execute in class QueryImpl<List<E>,E,T>

Returns:

the result of the Query execution.

iterator

public Iterator<E> iterator()

Description copied from interface: ListQuery

Executes the query and returns the matching objects as Iterator. This method may be overridden for database technology implementations that have native support for Iterator (unlike JPA). In such case this method is way more efficient if you only need to iterate the results to a specific point without the need to know the number of matches. If possible you shall prefer this method over Query.execute().

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface ListQuery<E>

Returns:

an Iterator of the results.

iteratorInternal

private Iterator<T> iteratorInternal()