/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.annotations;

import org.hibernate.engine.spi.QueryParameters;

Consolidation of hints available to Hibernate JPA queries.  Mainly used to define features available on
Hibernate queries that have no corollary in JPA queries.
/**
 * Consolidation of hints available to Hibernate JPA queries.  Mainly used to define features available on
 * Hibernate queries that have no corollary in JPA queries.
 */
public class QueryHints {
	
Disallow instantiation.
/**
	 * Disallow instantiation.
	 */
	private QueryHints() {
	}

	
The cache mode to use.
See Also:
setCacheMode.setCacheMode
SQLQuery.setCacheMode/**
	 * The cache mode to use.
	 *
	 * @see org.hibernate.Query#setCacheMode
	 * @see org.hibernate.SQLQuery#setCacheMode
	 */
	public static final String CACHE_MODE = "org.hibernate.cacheMode";

	
The cache region to use.
See Also:
setCacheRegion.setCacheRegion
SQLQuery.setCacheRegion/**
	 * The cache region to use.
	 *
	 * @see org.hibernate.Query#setCacheRegion
	 * @see org.hibernate.SQLQuery#setCacheRegion
	 */
	public static final String CACHE_REGION = "org.hibernate.cacheRegion";

	
Are the query results cacheable?
See Also:
setCacheable.setCacheable
SQLQuery.setCacheable/**
	 * Are the query results cacheable?
	 *
	 * @see org.hibernate.Query#setCacheable
	 * @see org.hibernate.SQLQuery#setCacheable
	 */
	public static final String CACHEABLE = "org.hibernate.cacheable";

	
Is the query callable?  Note: only valid for named native sql queries.
/**
	 * Is the query callable?  Note: only valid for named native sql queries.
	 */
	public static final String CALLABLE = "org.hibernate.callable";

	
Defines a comment to be applied to the SQL sent to the database.
See Also:
setComment.setComment
SQLQuery.setComment/**
	 * Defines a comment to be applied to the SQL sent to the database.
	 *
	 * @see org.hibernate.Query#setComment
	 * @see org.hibernate.SQLQuery#setComment
	 */
	public static final String COMMENT = "org.hibernate.comment";

	
Defines the JDBC fetch size to use.
See Also:
setFetchSize.setFetchSize
SQLQuery.setFetchSize/**
	 * Defines the JDBC fetch size to use.
	 *
	 * @see org.hibernate.Query#setFetchSize
	 * @see org.hibernate.SQLQuery#setFetchSize
	 */
	public static final String FETCH_SIZE = "org.hibernate.fetchSize";

	
The flush mode to associate with the execution of the query.
See Also:
setFlushMode.setFlushMode
SQLQuery.setFlushMode
Session.setFlushMode/**
	 * The flush mode to associate with the execution of the query.
	 *
	 * @see org.hibernate.Query#setFlushMode
	 * @see org.hibernate.SQLQuery#setFlushMode
	 * @see org.hibernate.Session#setFlushMode
	 */
	public static final String FLUSH_MODE = "org.hibernate.flushMode";

	
Should entities returned from the query be set in read only mode?
See Also:
setReadOnly.setReadOnly
SQLQuery.setReadOnly
Session.setReadOnly/**
	 * Should entities returned from the query be set in read only mode?
	 *
	 * @see org.hibernate.Query#setReadOnly
	 * @see org.hibernate.SQLQuery#setReadOnly
	 * @see org.hibernate.Session#setReadOnly
	 */
	public static final String READ_ONLY = "org.hibernate.readOnly";

	
Apply a Hibernate query timeout, which is defined in seconds.
See Also:
setTimeout.setTimeout
SQLQuery.setTimeout/**
	 * Apply a Hibernate query timeout, which is defined in <b>seconds</b>.
	 *
	 * @see org.hibernate.Query#setTimeout
	 * @see org.hibernate.SQLQuery#setTimeout
	 */
	public static final String TIMEOUT_HIBERNATE = "org.hibernate.timeout";

	
Apply a JPA query timeout, which is defined in milliseconds.
/**
	 * Apply a JPA query timeout, which is defined in <b>milliseconds</b>.
	 */
	public static final String TIMEOUT_JPA = "javax.persistence.query.timeout";

	
Available to apply lock mode to a native SQL query since JPA requires that Query.setLockMode throw an IllegalStateException if called for a native query. 
 Accepts a LockModeType or a LockMode /**
	 * Available to apply lock mode to a native SQL query since JPA requires that
	 * {@link javax.persistence.Query#setLockMode} throw an IllegalStateException if called for a native query.
	 * <p/>
	 * Accepts a {@link javax.persistence.LockModeType} or a {@link org.hibernate.LockMode}
	 */
	public static final String NATIVE_LOCKMODE = "org.hibernate.lockMode";
	
	
Hint providing a "fetchgraph" EntityGraph.  Attributes explicitly specified as AttributeNodes are treated as
FetchType.EAGER (via join fetch or subsequent select).
Note: Currently, attributes that are not specified are treated as FetchType.LAZY or FetchType.EAGER depending
on the attribute's definition in metadata, rather than forcing FetchType.LAZY.
/**
	 * Hint providing a "fetchgraph" EntityGraph.  Attributes explicitly specified as AttributeNodes are treated as
	 * FetchType.EAGER (via join fetch or subsequent select).
	 * 
	 * Note: Currently, attributes that are not specified are treated as FetchType.LAZY or FetchType.EAGER depending
	 * on the attribute's definition in metadata, rather than forcing FetchType.LAZY.
	 */
	public static final String FETCHGRAPH = "javax.persistence.fetchgraph";
	
	
Hint providing a "loadgraph" EntityGraph.  Attributes explicitly specified as AttributeNodes are treated as
FetchType.EAGER (via join fetch or subsequent select).  Attributes that are not specified are treated as
FetchType.LAZY or FetchType.EAGER depending on the attribute's definition in metadata
/**
	 * Hint providing a "loadgraph" EntityGraph.  Attributes explicitly specified as AttributeNodes are treated as
	 * FetchType.EAGER (via join fetch or subsequent select).  Attributes that are not specified are treated as
	 * FetchType.LAZY or FetchType.EAGER depending on the attribute's definition in metadata
	 */
	public static final String LOADGRAPH = "javax.persistence.loadgraph";

	
Hint to enable/disable the follow-on-locking mechanism provided by Dialect.useFollowOnLocking(QueryParameters). A value of true enables follow-on-locking, whereas a value of false disables it. If the value is null, the the Dialect strategy is going to be used instead. 
Since:
5.2/**
	 * Hint to enable/disable the follow-on-locking mechanism provided by {@link org.hibernate.dialect.Dialect#useFollowOnLocking(QueryParameters)}.
	 * A value of {@code true} enables follow-on-locking, whereas a value of {@code false} disables it.
	 * If the value is {@code null}, the the {@code Dialect} strategy is going to be used instead.
	 *
	 * @since 5.2
	 */
	public static final String FOLLOW_ON_LOCKING = "hibernate.query.followOnLocking";

	
Hint to enable/disable the pass-distinct-through mechanism. A value of true enables pass-distinct-through, whereas a value of false disables it. When the pass-distinct-through is disabled, the HQL and JPQL distinct clause is no longer passed to the SQL statement. 
Since:
5.2/**
	 * Hint to enable/disable the pass-distinct-through mechanism.
	 * A value of {@code true} enables pass-distinct-through, whereas a value of {@code false} disables it.
	 * When the pass-distinct-through is disabled, the HQL and JPQL distinct clause is no longer passed to the SQL statement.
	 *
	 * @since 5.2
	 */
	public static final String PASS_DISTINCT_THROUGH = "hibernate.query.passDistinctThrough";

}