org.springframework.data.jpa.repository.query

Class QueryUtils

java.lang.Object

org.springframework.data.jpa.repository.query.QueryUtils

public abstract class QueryUtils
extends Object

Simple utility class to create JPA queries.

Author:

Oliver Gierke, Kevin Raymond, Thomas Darimont, Komi Innocent

Field Summary

Fields

Modifier and Type	Field and Description
static String	COUNT_QUERY_STRING
static String	DELETE_ALL_QUERY_STRING

Method Summary

Modifier and Type	Method and Description
static <T> javax.persistence.Query	applyAndBind(String queryString, Iterable<T> entities, javax.persistence.EntityManager entityManager) Creates a where-clause referencing the given entities and appends it to the given query string.
static String	applySorting(String query, Sort sort) Adds order by clause to the JPQL query.
static String	applySorting(String query, Sort sort, String alias) Adds order by clause to the JPQL query.
static String	createCountQueryFor(String originalQuery) Creates a count projected query from the given original query.
static String	createCountQueryFor(String originalQuery, String countProjection) Creates a count projected query from the given original query.
static String	detectAlias(String query) Resolves the alias for the entity to be retrieved from the given JPA query.
static String	getExistsQueryString(String entityName, String countQueryPlaceHolder, Iterable<String> idAttributes) Returns the query string to execute an exists query for the given id attributes.
static String	getQueryString(String template, String entityName) Returns the query string for the given class name.
static boolean	hasConstructorExpression(String query) Returns whether the given JPQL query contains a constructor expression.
static boolean	hasNamedParameter(javax.persistence.Query query) Returns whether the given Query contains named parameters.
static boolean	hasNamedParameter(String query) Returns whether the given query contains named parameters.
static List<javax.persistence.criteria.Order>	toOrders(Sort sort, javax.persistence.criteria.Root<?> root, javax.persistence.criteria.CriteriaBuilder cb) Turns the given Sort into Orders.

Methods inherited from class java.lang.Object

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

Field Detail

COUNT_QUERY_STRING

public static final String COUNT_QUERY_STRING

See Also:

Constant Field Values

DELETE_ALL_QUERY_STRING

public static final String DELETE_ALL_QUERY_STRING

See Also:

Constant Field Values

Method Detail

getExistsQueryString

public static String getExistsQueryString(String entityName,
                                          String countQueryPlaceHolder,
                                          Iterable<String> idAttributes)

Returns the query string to execute an exists query for the given id attributes.

Parameters:

entityName - the name of the entity to create the query for, must not be null.

countQueryPlaceHolder - the placeholder for the count clause, must not be null.

idAttributes - the id attributes for the entity, must not be null.

Returns:

getQueryString

public static String getQueryString(String template,
                                    String entityName)

Returns the query string for the given class name.

Parameters:

template -

entityName -

Returns:

applySorting

public static String applySorting(String query,
                                  Sort sort)

Adds order by clause to the JPQL query. Uses the DEFAULT_ALIAS to bind the sorting property to.

Parameters:

query -

sort -

Returns:

applySorting

public static String applySorting(String query,
                                  Sort sort,
                                  String alias)

Adds order by clause to the JPQL query.

Parameters:

query -

sort -

alias -

Returns:

detectAlias

public static String detectAlias(String query)

Resolves the alias for the entity to be retrieved from the given JPA query.

Parameters:

query -

Returns:

applyAndBind

public static <T> javax.persistence.Query applyAndBind(String queryString,
                                                       Iterable<T> entities,
                                                       javax.persistence.EntityManager entityManager)

Creates a where-clause referencing the given entities and appends it to the given query string. Binds the given entities to the query.

Type Parameters:

T -

Parameters:

queryString -

entities -

entityManager -

Returns:

createCountQueryFor

public static String createCountQueryFor(String originalQuery)

Creates a count projected query from the given original query.

Parameters:

originalQuery - must not be null or empty.

Returns:

createCountQueryFor

public static String createCountQueryFor(String originalQuery,
                                         String countProjection)

Creates a count projected query from the given original query.

Parameters:

originalQuery - must not be null.

countProjection - may be null.

Returns:

Since:

1.6

hasNamedParameter

public static boolean hasNamedParameter(javax.persistence.Query query)

Returns whether the given Query contains named parameters.

Parameters:

query -

Returns:

hasNamedParameter

public static boolean hasNamedParameter(String query)

Returns whether the given query contains named parameters.

Parameters:

query - can be null or empty.

Returns:

toOrders

public static List<javax.persistence.criteria.Order> toOrders(Sort sort,
                                                              javax.persistence.criteria.Root<?> root,
                                                              javax.persistence.criteria.CriteriaBuilder cb)

Turns the given Sort into Orders.

Parameters:

sort - the Sort instance to be transformed into JPA Orders.

root - must not be null.

cb - must not be null.

Returns:

hasConstructorExpression

public static boolean hasConstructorExpression(String query)

Returns whether the given JPQL query contains a constructor expression.

Parameters:

query - must not be null or empty.

Returns:

Since:

1.10