info.joseluismartin.dao.jpa
Class JpaUtils

java.lang.Object
  info.joseluismartin.dao.jpa.JpaUtils

public abstract class JpaUtils
extends Object

Utility class for dealing with JPA API

Since:

1.1

Author:

Jose Luis Martin

Constructor Summary

JpaUtils()

Method Summary

static String	addOrder(String queryString, String propertyPath, boolean asc) Add order by clause to queryString
static <T> void	copyCriteria(javax.persistence.criteria.CriteriaQuery<T> from, javax.persistence.criteria.CriteriaQuery<T> to)
static void	copyCriteriaNoSelection(javax.persistence.criteria.CriteriaQuery<?> from, javax.persistence.criteria.CriteriaQuery<?> to) Copy Criteria without Selection
static void	copyFetches(javax.persistence.criteria.Fetch<?,?> from, javax.persistence.criteria.Fetch<?,?> to) Copy Fetches
static void	copyJoins(javax.persistence.criteria.From<?,?> from, javax.persistence.criteria.From<?,?> to) Copy Joins
static <T> Long	count(javax.persistence.EntityManager em, javax.persistence.criteria.CriteriaQuery<T> criteria) Result count from a CriteriaQuery
static <T> javax.persistence.criteria.CriteriaQuery<Long>	countCriteria(javax.persistence.EntityManager em, javax.persistence.criteria.CriteriaQuery<T> criteria) Create a row count CriteriaQuery from a CriteriaQuery
static String	createCountQueryString(String queryString) Create a count query string from a query string
static <T,K> javax.persistence.criteria.Join<T,K>	findJoinedType(javax.persistence.criteria.CriteriaQuery<T> query, Class<T> rootClass, Class<K> joinClass) Find Joined Root of type clazz
static <T> javax.persistence.criteria.Root<T>	findRoot(javax.persistence.criteria.CriteriaQuery<?> query, Class<T> clazz) Find the Root with type class on CriteriaQuery Root Set
static <T> javax.persistence.criteria.Root<T>	findRoot(javax.persistence.criteria.CriteriaQuery<T> query) Find Root of result type
static String	getAlias(String queryString) Gets the alias of root entity of JQL query
static String	getKeyQuery(String queryString, String name) Gets Query String for selecting primary keys
static <T> String	getOrCreateAlias(javax.persistence.criteria.Selection<T> selection) Gets The result alias, if none set a default one and return it
static javax.persistence.criteria.Path<?>	getPath(javax.persistence.criteria.Path<?> path, String propertyPath) Gets a Path from Path using property path

Methods inherited from class java.lang.Object

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

Constructor Detail

JpaUtils

public JpaUtils()

Method Detail

count

public static <T> Long count(javax.persistence.EntityManager em,
                             javax.persistence.criteria.CriteriaQuery<T> criteria)

Result count from a CriteriaQuery

Parameters:

em - Entity Manager

criteria - Criteria Query to count results

Returns:

row count

countCriteria

public static <T> javax.persistence.criteria.CriteriaQuery<Long> countCriteria(javax.persistence.EntityManager em,
                                                                               javax.persistence.criteria.CriteriaQuery<T> criteria)

Create a row count CriteriaQuery from a CriteriaQuery

Parameters:

em - entity manager

criteria - source criteria

Returns:

row coutnt CriteriaQuery

getOrCreateAlias

public static <T> String getOrCreateAlias(javax.persistence.criteria.Selection<T> selection)

Gets The result alias, if none set a default one and return it

Parameters:

selection -

Returns:

root alias or generated one

findRoot

public static <T> javax.persistence.criteria.Root<T> findRoot(javax.persistence.criteria.CriteriaQuery<T> query)

Find Root of result type

Parameters:

query - criteria query

Returns:

the root of result type or null if none

findRoot

public static <T> javax.persistence.criteria.Root<T> findRoot(javax.persistence.criteria.CriteriaQuery<?> query,
                                                              Class<T> clazz)

Find the Root with type class on CriteriaQuery Root Set

Type Parameters:

T - root type

Parameters:

query - criteria query

clazz - root type

Returns:

Root of null if none

findJoinedType

public static <T,K> javax.persistence.criteria.Join<T,K> findJoinedType(javax.persistence.criteria.CriteriaQuery<T> query,
                                                                        Class<T> rootClass,
                                                                        Class<K> joinClass)

Find Joined Root of type clazz

Type Parameters:

T -

Parameters:

query - the criteria query

rootClass - the root class

joinClass - the join class

Returns:

the Join

getPath

public static javax.persistence.criteria.Path<?> getPath(javax.persistence.criteria.Path<?> path,
                                                         String propertyPath)

Gets a Path from Path using property path

Parameters:

path - the base path

propertyPath - property path String like "customer.order.price"

Returns:

a new Path for property

createCountQueryString

public static String createCountQueryString(String queryString)

Create a count query string from a query string

Parameters:

queryString - string to parse

Returns:

the count query string

getAlias

public static String getAlias(String queryString)

Gets the alias of root entity of JQL query

Parameters:

queryString - JQL query

Returns:

alias of root entity.

addOrder

public static String addOrder(String queryString,
                              String propertyPath,
                              boolean asc)

Add order by clause to queryString

Parameters:

queryString - JPL Query String

propertyPath - Order properti

asc - true if ascending

Returns:

JQL Query String with Order clause appened.

getKeyQuery

public static String getKeyQuery(String queryString,
                                 String name)

Gets Query String for selecting primary keys

Parameters:

queryString - the original query

name - primary key name

Returns:

query string

copyCriteriaNoSelection

public static void copyCriteriaNoSelection(javax.persistence.criteria.CriteriaQuery<?> from,
                                           javax.persistence.criteria.CriteriaQuery<?> to)

Copy Criteria without Selection

Parameters:

from - source Criteria

to - destination Criteria

copyCriteria

public static <T> void copyCriteria(javax.persistence.criteria.CriteriaQuery<T> from,
                                    javax.persistence.criteria.CriteriaQuery<T> to)

copyJoins

public static void copyJoins(javax.persistence.criteria.From<?,?> from,
                             javax.persistence.criteria.From<?,?> to)

Copy Joins

Parameters:

from - source Join

to - destination Join

copyFetches

public static void copyFetches(javax.persistence.criteria.Fetch<?,?> from,
                               javax.persistence.criteria.Fetch<?,?> to)

Copy Fetches

Parameters:

from - source Fetch

to - dest Fetch