Package ch.tocco.nice2.persist.core.impl.hibernate.pojo

Class EmptyQuery

java.lang.Object

ch.tocco.nice2.persist.core.spi.entity.query.ql.AbstractOrderableQuery

ch.tocco.nice2.persist.core.impl.hibernate.pojo.AbstractHibernateQueryAdapter

ch.tocco.nice2.persist.core.impl.hibernate.pojo.EmptyQuery

All Implemented Interfaces:

Query

public class EmptyQuery
extends AbstractHibernateQueryAdapter

Query implementation that can be used when no results will be available.

Nested Class Summary

Nested classes/interfaces inherited from interface ch.tocco.nice2.persist.core.api.query.Query

Query.Mode

Field Summary

Fields inherited from class ch.tocco.nice2.persist.core.impl.hibernate.pojo.AbstractHibernateQueryAdapter

entityManager

Fields inherited from class ch.tocco.nice2.persist.core.spi.entity.query.ql.AbstractOrderableQuery

ordering

Constructor Summary

Constructors

Constructor	Description
EmptyQuery(EntityManager entityManager)

Method Summary

Modifier and Type	Method	Description
int	count()	Currently badly implemented! Count the results.
EntityList	execute(Pagination pagination, Query.Mode mode)	Execute the query using the specified pagination parameters in the specified Query.Mode.
@Nullable Entity	getOnlyResultOrNull(LockMode lockMode)
void	setParameter(String name, Object value)	Set a parameter for the query.
QueryDefinition	toQueryDefinition()

Methods inherited from class ch.tocco.nice2.persist.core.impl.hibernate.pojo.AbstractHibernateQueryAdapter

execute, execute, execute, execute, execute, firstResult, firstResultOrNull, getManager, getOnlyResult, getOnlyResult, getOnlyResultOrNull, uniqueResult, uniqueResultOrNull

Methods inherited from class ch.tocco.nice2.persist.core.spi.entity.query.ql.AbstractOrderableQuery

appendOrder, getOrdering, hasOrdering, prependOrder, withOrder

Methods inherited from class java.lang.Object

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

Methods inherited from interface ch.tocco.nice2.persist.core.api.query.Query

getKeys, getKeys

Constructor Details

EmptyQuery

public EmptyQuery(EntityManager entityManager)

Method Details

setParameter

public void setParameter(String name,
 Object value)
                  throws PersistException

Description copied from interface: Query

Set a parameter for the query.

Parameters:

name - The name of the parameter

value - The value of the parameter in the correct data type.

Throws:

PersistException - If the parameter cannot be set (invalid name, invalid value)

execute

public EntityList execute(Pagination pagination,
 Query.Mode mode)

Description copied from interface: Query

Execute the query using the specified pagination parameters in the specified Query.Mode.

Parameters:

pagination - The offset and limit of the query.

mode - The mode.

Returns:

The result of the query.

getOnlyResultOrNull

@Nullable
public @Nullable Entity getOnlyResultOrNull(LockMode lockMode)

count

public int count()
          throws PersistException

Description copied from interface: Query

Currently badly implemented! Count the results.

WARNING: This method does not behave as "SELECT count()" in SQL does! In fact it is temporarily implemented as a chaining of execute().size() only. No query modification is done etc. ALSO, the default query limit is used and thus if there would be more records, only the default limit is returned. The impl may be rewritten to be what one would expect; until then users may only use this method if they can live with today's limits: small counts.

Speed of "SELECT count()" greatly depends on the underlying db table impl. An example are the two MySQL table types MyISAM and InnoDB. A query-less count on the former returns instantly because it keeps track of the number, whereas the latter needs to iterate over all records (at least in case of non-fixed length record tables) and can take minutes depending on the size.

Returns:

The count.

Throws:

PersistException - If an error occurs.

toQueryDefinition

public QueryDefinition toQueryDefinition()