Package org.nuclos.api.provider

Class QueryProvider

java.lang.Object

org.nuclos.api.provider.QueryProvider

public class QueryProvider
extends Object

QueryProvider provides methods for creating and executing Query for data access and methods to read single BusinessObject.

This Class is usually used in Rule-classes and allows API access only

Author:

Matthias Reichart

See Also:

• Query
• BusinessObject

Constructor Summary

Constructors

Constructor	Description
QueryProvider()

Method Summary

Modifier and Type	Method	Description
static <PK, T extends BusinessObject<PK>> Query<T>	create(Class<T> type)	This methods returns an instance of Query that is type-specific to the class given as parameter.
static <PK, T extends BusinessObject<PK>> List<T>	execute(Query<T> query, Attribute<?>... attributes)	This methods executes a Query and returns a list of found BusinessObject of the type determined by the Query type.
static <PK, T extends BusinessObject<PK>> T	executeSingleResult(Query<T> query, Attribute<?>... attributes)	This methods executes a Query and returns a single result BusinessObject of the type determined by the Query type.
static <PK, T extends BusinessObject<PK>> T	getById(Class<T> type, PK id, Attribute<?>... attributes)	Deprecated.
static <T extends Stateful> List<T>	getByProcess(Process<T> process, Process<T>... additionalProcesses)	This method returns all BusinessObjects that contain one of the given processes; A Process is always assigned to one entity, so the type of the BusinessObject does not have to be mentioned explicitly; There must be at least one process
static <T extends Stateful> List<T>	getByState(Class<T> type, State state, State... additionalStates)	This method returns all BusinessObjects that contain one of the given states; A State is always assigned to one statemodel, that can be used by several entities.
void	setQueryService(QueryService service)

Methods inherited from class java.lang.Object

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

Constructor Details

QueryProvider

QueryProvider()

Method Details

setQueryService

public void setQueryService(QueryService service)

create

public static <PK,
T extends BusinessObject<PK>>
Query<T> create(Class<T> type)

This methods returns an instance of Query that is type-specific to the class given as parameter. The Query can executed by using method execute(BusinessObjectQuery<T> query)

Parameters:

type - - type-specific class that determines the type of the returned Query

Returns:

Query

execute

public static <PK,
T extends BusinessObject<PK>>
List<T> execute(Query<T> query,
 Attribute<?>... attributes)

This methods executes a Query and returns a list of found BusinessObject of the type determined by the Query type. An IllegalArgumentException is thrown if an attribute is compared to null and NULL or NOTNULL is not used.

Parameters:

query - type-specific list of BusinessObject

Returns:

List<BusinessObject>

executeSingleResult

public static <PK,
T extends BusinessObject<PK>> T executeSingleResult(Query<T> query,
 Attribute<?>... attributes)
                                                               throws BusinessException

This methods executes a Query and returns a single result BusinessObject of the type determined by the Query type. Returns null if nothing found and throws exception if query returns more than one row. An IllegalArgumentException is thrown if an attribute is compared to null and NULL or NOTNULL is not used.

Parameters:

query - type-specific BusinessObject

Returns:

BusinessObject;

Throws:

BusinessException

getById

@Deprecated
public static <PK,
T extends BusinessObject<PK>> T getById(Class<T> type,
 PK id,
 Attribute<?>... attributes)

Deprecated.

This method returns one single BusinessObject that can be found for the given Id; Parameter Class<T> type is necessary to ensure type-safety

Parameters:

type - - type-specific class

id - - Id of the element to search for in the database

Returns:

type-specific - BusinessObject

getByProcess

public static <T extends Stateful> List<T> getByProcess(Process<T> process,
 Process<T>... additionalProcesses)
                                                 throws BusinessException

This method returns all BusinessObjects that contain one of the given processes;
A Process is always assigned to one entity, so the type of the BusinessObject does not have to be mentioned explicitly;
There must be at least one process

Parameters:

process -

additionalProcesses -

Returns:

Throws:

BusinessException

getByState

public static <T extends Stateful> List<T> getByState(Class<T> type,
 State state,
 State... additionalStates)
                                               throws BusinessException

This method returns all BusinessObjects that contain one of the given states;
A State is always assigned to one statemodel, that can be used by several entities. So the type of the BusinessObject must be mentioned explicitly;
There must be at least one state

Parameters:

type -

state -

additionalStates -

Returns:

Throws:

BusinessException