org.eclipse.persistence.dynamic
Class DynamicHelper

java.lang.Object
  org.eclipse.persistence.dynamic.DynamicHelper

Direct Known Subclasses:

JPADynamicHelper

public class DynamicHelper
extends java.lang.Object

A DynamicHelper provides some utility methods to simplify application development with dynamic types. Since the application does not have static references to the dynamic types it must use entity names. This helper provides simplified access to methods that would typically require the static classes.

Author:

dclarke, mnorman

Since:

EclipseLink 1.2

Nested Class Summary

static class

DynamicHelper.SessionCustomizer A SessionCustomizer which configures all descriptors as dynamic entity types.

Field Summary

protected java.util.Map<java.lang.String,ClassDescriptor>	fqClassnameToDescriptor
protected DatabaseSession	session

Constructor Summary

DynamicHelper(DatabaseSession session)

Method Summary

void	addTypes(boolean createMissingTables, boolean generateFKConstraints, DynamicType... types) Add one or more EntityType instances to a session and optionally generate needed tables with or without FK constraints.
DynamicClassLoader	getDynamicClassLoader()
DatabaseSession	getSession()
static DynamicType	getType(ClassDescriptor descriptor)
static DynamicType	getType(DynamicEntity entity) Provide access to the entity's type.
DynamicType	getType(java.lang.String typeName) Lookup the dynamic type for an alias.
DynamicEntity	newDynamicEntity(java.lang.String typeName)
ReadAllQuery	newReadAllQuery(java.lang.String typeName) Helper method to simplify creating a native ReadAllQuery using the entity type name (descriptor alias)
ReadObjectQuery	newReadObjectQuery(java.lang.String typeName) Helper method to simplify creating a native ReadObjectQuery using the entity type name (descriptor alias)
ReportQuery	newReportQuery(java.lang.String typeName, ExpressionBuilder builder) Helper method to simplify creating a native ReportQuery using the entity type name (descriptor alias)
void	removeType(java.lang.String typeName) Remove a dynamic type from the system.

Methods inherited from class java.lang.Object

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

Field Detail

session

protected DatabaseSession session

fqClassnameToDescriptor

protected java.util.Map<java.lang.String,ClassDescriptor> fqClassnameToDescriptor

Constructor Detail

DynamicHelper

public DynamicHelper(DatabaseSession session)

Method Detail

getSession

public DatabaseSession getSession()

getType

public DynamicType getType(java.lang.String typeName)

Lookup the dynamic type for an alias. This is required to get the type for factory creation but can also be used to provide the application with access to the meta model (type and properties) allowing for dynamic use as well as optimized data value retrieval from an entity.

getType

public static DynamicType getType(ClassDescriptor descriptor)

getType

public static DynamicType getType(DynamicEntity entity)
                           throws java.lang.ClassCastException

Provide access to the entity's type.

Parameters:

entity -

Returns:

Throws:

java.lang.ClassCastException - if entity is not an instance of DynamicEntityImpl

removeType

public void removeType(java.lang.String typeName)

Remove a dynamic type from the system. This implementation assumes that the dynamic type has no relationships to it and that it is not involved in an inheritance relationship. If there are concurrent processes using this type when it is removed some exceptions may occur.

Parameters:

session -

typeName -

newDynamicEntity

public DynamicEntity newDynamicEntity(java.lang.String typeName)

newReadAllQuery

public ReadAllQuery newReadAllQuery(java.lang.String typeName)

Helper method to simplify creating a native ReadAllQuery using the entity type name (descriptor alias)

newReadObjectQuery

public ReadObjectQuery newReadObjectQuery(java.lang.String typeName)

Helper method to simplify creating a native ReadObjectQuery using the entity type name (descriptor alias)

newReportQuery

public ReportQuery newReportQuery(java.lang.String typeName,
                                  ExpressionBuilder builder)

Helper method to simplify creating a native ReportQuery using the entity type name (descriptor alias)

getDynamicClassLoader

public DynamicClassLoader getDynamicClassLoader()

addTypes

public void addTypes(boolean createMissingTables,
                     boolean generateFKConstraints,
                     DynamicType... types)

Add one or more EntityType instances to a session and optionally generate needed tables with or without FK constraints.

Parameters:

session -

createMissingTables -

generateFKConstraints -

types -