com.neurosys.dao.jpa

Class AbstractQueryableDaoImpl<T>

java.lang.Object

com.neurosys.domain.GenericAware<T>

com.neurosys.dao.jpa.GenericDaoImpl<T>

com.neurosys.dao.jpa.AbstractQueryableDaoImpl<T>

All Implemented Interfaces:

FreeQuery, GenericDao<T>, QueryableDao<T>

Direct Known Subclasses:

AbstractConfigurationJPADaoImpl, AbstractHierarchyDaoImpl, DefaultTransactionService, EventsDaoImpl, GenericObjectDaoImpl, GenericQueryableDaoImpl, LogisticsDaoImpl, OrderDaoImpl, PromotionDaoImpl, RatingDaoImpl, UserDaoImpl

public class AbstractQueryableDaoImpl<T>
extends GenericDaoImpl<T>
implements QueryableDao<T>

A generic DAO Impl of higher order queries & criteria & pagination.
Though intended to be also an abstract class, the getQueryObject(Query, boolean) is a useful method by itself.

Author:

Arjun Dhar

Field Summary

Fields inherited from class com.neurosys.dao.jpa.GenericDaoImpl

em

Fields inherited from class com.neurosys.domain.GenericAware

ct, t

Constructor Summary

Constructors

Constructor and Description
AbstractQueryableDaoImpl()
AbstractQueryableDaoImpl(Class<T> t)

Method Summary

Modifier and Type	Method and Description
protected String	conditionConstruct(String name, Object value, Field f, Map<String,Object[]> querableFieldNames) Construct the Where clause of the Query.
Long	count(Query<T> query) Execute Query and on Queryable fields only.
protected static <SUB_T,T> List<SUB_T>	ensureRowIsEntity(List<T> rows, List<String> resultFieldNames, Class<T> queryClass, Class<SUB_T> resultClass) Due to varied column selection, it is possible that result rows may not be an Entity SUB_T.
protected List<T>	ensureRowIsEntity(Query<T> query, List rows, List<String> resultFieldNames) Due to varied column selection, it is possible that result rows may not be an Entity T.
T	getEntityInstance() The entity instance maybe an extension of the Base ensure Queries work for extensions derive the exact instance required for the Query.
protected ExtendedJPAQuery	getQueryObject(Query<T> query, boolean count) Create a {javax.persistence.Query} object based on conditions and criteria (input domain based Query)
List<T>	query(Query<T> query) Execute Query and on Queryable fields only.
<SUB_T> List<SUB_T>	query(Query<T> query, Class<SUB_T> claz) Derive a SubSet (claz) of T only as an queried entity.
Page<T>	queryPage(Query<T> query) Execute Query and on Queryable fields only.
<SUB_T> Page<SUB_T>	queryPage(Query<T> query, Class<SUB_T> claz) Derive a SubSet (claz) of T only as an queried entity.

Methods inherited from class com.neurosys.dao.jpa.GenericDaoImpl

delete, delete, getEntityManager, getNativeEntityName, load, load, paginate, query, query, save, setEntityManager, update

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.neurosys.dao.GenericDao

delete, delete, load, load, save

Methods inherited from interface com.neurosys.dao.FreeQuery

query, query, update

Constructor Detail

AbstractQueryableDaoImpl

public AbstractQueryableDaoImpl()

AbstractQueryableDaoImpl

public AbstractQueryableDaoImpl(Class<T> t)

Method Detail

getEntityInstance

public T getEntityInstance()

Description copied from interface: QueryableDao

The entity instance maybe an extension of the Base ensure Queries work for extensions derive the exact instance required for the Query.

Specified by:

getEntityInstance in interface QueryableDao<T>

Returns:

conditionConstruct

protected String conditionConstruct(String name,
                                    Object value,
                                    Field f,
                                    Map<String,Object[]> querableFieldNames)

Construct the Where clause of the Query. This is only called if for a given field Queryable annotation is defined.

Parameters:

name - as String

value - as the Value (for the criteria) for the field name

f - as Field

querableFieldNames - as Map of String Object[]

Returns:

WHERE part of QL as String

getQueryObject

protected ExtendedJPAQuery getQueryObject(Query<T> query,
                                          boolean count)
                                   throws Exception

Create a {javax.persistence.Query} object based on conditions and criteria (input domain based Query)

Parameters:

query - as Query

count - as boolean; if true will convert the query to return just a count, in which case dropIfLargeAmt is ignored

Returns:

ExtendedJPAQuery

Throws:

Exception

ensureRowIsEntity

protected final List<T> ensureRowIsEntity(Query<T> query,
                                          List rows,
                                          List<String> resultFieldNames)
                                   throws Exception

Due to varied column selection, it is possible that result rows may not be an Entity T.

Parameters:

query - as Query of T

rows - as List of Object[] (result) of raw query

resultFieldNames - as List<String>.
One can use com.neurosys.utils.BeanUtils.getDeclaredFields(entityClass) to derive field order of resultset also, but thats more risky.

Returns:

List of desired entities

Throws:

Exception

ensureRowIsEntity

protected static <SUB_T,T> List<SUB_T> ensureRowIsEntity(List<T> rows,
                                                         List<String> resultFieldNames,
                                                         Class<T> queryClass,
                                                         Class<SUB_T> resultClass)
                                                  throws Exception

Due to varied column selection, it is possible that result rows may not be an Entity SUB_T.
Note: SUB_T does not extend T

Parameters:

rows - as List of Object[] (result) of raw query

resultFieldNames - as List<String>

queryClass - as Class of T

resultClass - as Class of SUB_T

Returns:

List of desired entities

Throws:

Exception - if resultFieldNames is not provided

query

public List<T> query(Query<T> query)
              throws Exception

Execute Query and on Queryable fields only.
If a field is to be search on NULL, then explicitly add the Java field name to the nullSet
Also note that beans that do not follow standard java bean naming conventions; on their Queryable fields will face problems.

Specified by:

query in interface QueryableDao<T>

Parameters:

query - as Queryable

Throws:

Exception

queryPage

public Page<T> queryPage(Query<T> query)
                  throws Exception

Execute Query and on Queryable fields only.
If a field is to be search on NULL, then explicitly add the Java field name to the Query.setNullSet(Set)
Also note that beans that do not follow standard java bean naming conventions; on their Queryable fields will face problems.

Specified by:

queryPage in interface QueryableDao<T>

Parameters:

query - as Queryable

Throws:

Exception

count

public Long count(Query<T> query)
           throws Exception

Execute Query and on Queryable fields only.
If a field is to be search on NULL, then explicitly add the Java field name to the Query.setNullSet(Set)
Also note that beans that do not follow standard java bean naming conventions; on their Queryable fields will face problems.

Specified by:

count in interface QueryableDao<T>

Parameters:

query - as Queryable

Throws:

Exception

query

public <SUB_T> List<SUB_T> query(Query<T> query,
                                 Class<SUB_T> claz)
                          throws Exception

Derive a SubSet (claz) of T only as an queried entity. The result entity should have common accessor methods as queried Entity.
The above technically translates to Result Fields = Query.setExcludedFields(T-class)

Specified by:

query in interface QueryableDao<T>

Parameters:

query - as Query

claz - as Class

Returns:

an object that contains properties that is a Sub Set of T, Note SUB_T does not even have to extend T.

Throws:

Exception

queryPage

public <SUB_T> Page<SUB_T> queryPage(Query<T> query,
                                     Class<SUB_T> claz)
                              throws Exception

Derive a SubSet (claz) of T only as an queried entity. The result entity should have common accessor methods as queried Entity.
The above technically translates to Result Fields = Query.setExcludedFields(T-class)

Specified by:

queryPage in interface QueryableDao<T>

Parameters:

query - as Query

claz - as Class

Returns:

an object that contains properties that is a Sub Set of T, Note SUB_T does not even have to extend T.

Throws:

Exception