PATH Documentation > WebObjects 4.5 > EOAdaptor Reference

EOModel

Inherits from: NSObject

Package: com.apple.yellow.eoaccess

Class Description

An EOModel represents a mapping between a database schema and a set of classes based on the entity-relationship model. The model contains a number of EOEntity objects representing the entities (tables) of the database schema. Each EOEntity object has a number of EOAttribute and EORelationship objects representing the properties (columns or fields) of the entity in the database schema. For more information on attributes and relationships, see their respective class specifications.

An EOModel maintains a mapping between each of its EOEntity objects and a corresponding enterprise object class for use with the database level of the Enterprise Objects Framework. You can determine the EOEntity for a particular enterprise object with the entityForObject method.

An EOModel is specific to a particular database server, and stores information needed to connect to that server. This includes the name of an adaptor framework to load so that the Enterprise Objects Framework can communicate with the database. Models are stored in the file system in a manner similar to adaptor framework. EOModel objects are usually loaded from model files built with the EOModeler application rather than built programmatically. If you need to programmatically load a model file, see the section "Loading a Model File" .

Models can have relationships that reference other models in the same model group. The other models may map to different databases and types of servers.

Models are organized into model groups; see the EOModelGroup class specification for more information.

Creating an EOModel Programmatically

The EOAdaptorChannel class declares methods for reading basic schema information from a relational database. You can use this information to build up an EOModel programmatically, and then enhance that model by defining extra relationships, flattening attributes, and so on. See the class description in the EOAdaptorChannel class specification for information on reading basic schema information, and see the other modeling classes' specifications for information on creating additional attributes and relationships.

Constants

EOModel defines a String constant for the name of the notification it posts. For more information, see "Notifications" .

Method Types

Constructors

EOModel

Saving a model

encodeTableOfContentsIntoPropertyList

writeToFile

Loading a model's objects

loadAllModelObjects

Working with entities

addEntity

removeEntity

removeEntityAndReferences

entityNames

entityNamed

entities

entitiesWithSharedObjects

Naming a model's components

beautifyNames

Accessing the model's name

setName

name

path

Checking references

referencesToProperty

externalModelsReferenced

Getting an object's entity

entityForObject

Accessing the adaptor bundle

adaptorName

setAdaptorName

Accessing the connection dictionary

setConnectionDictionary

connectionDictionary

Accessing the user dictionary

setUserInfo

userInfo

Working with stored procedures

addStoredProcedure

removeStoredProcedure

storedProcedureNames

storedProcedureNamed

storedProcedures

Accessing the model's group

setModelGroup

modelGroup

Accessing prototype attributes

availablePrototypeAttributeNames

prototypeAttributeNamed

Constructors

EOModel

public EOModel(String path)

Creates a new EOModel object by reading the contents of the file identified by path as a model archive. Sets the EOModel's name and path from the context of the model archive. Throws an exception if for any reason it cannot initialize the model from the file specified by path.

public EOModel( NSDictionary tableOfContents, String path)

Creates a new EOModel object from tableOfContents, which is the property list representation of a EOModel). Sets the EOModel's name and path using path.

Instance Methods

adaptorName

public String adaptorName()

Returns the name of the adaptor for the receiver. This name can be used with EOAdaptor's adaptorWithName static method to create an adaptor.

addEntity

public void addEntity(EOEntity anEntity)

Adds anEntity to the receiver. Throws an exception if an error occurs (for example, if anEntity doesn't exist, if the entity belongs to another model, or if an entity of the same name is already in the receiver).

addStoredProcedure

public void addStoredProcedure(EOStoredProcedure storedProcedure)

Adds storedProcedure to the receiver. Throws an exception if an error occurs (for example, if a stored procedure of the same name is already in the receiver).

availablePrototypeAttributeNames

public NSArray availablePrototypeAttributeNames()

Returns a list of available prototype names.

See Also: prototypeAttributeNamed

beautifyNames

public void beautifyNames()

Makes all of the receiver's named components conform to a standard convention. Names that conform to this style are all lower-case except for the initial letter of each embedded word other than the first, which is upper case. Thus, "NAME" becomes "name", and "FIRST_NAME" becomes "firstName".

See Also: nameForExternalName (EOEntity), beautifyName ( EOEntity, EOAttribute, EORelationship, EOStoredProcedure), name

connectionDictionary

public NSDictionary connectionDictionary()

Returns a dictionary containing information used to connect to the database server. The connection dictionary is the place to specify default login information for applications using the model. See the EOAdaptor class specification for more information.

encodeTableOfContentsIntoPropertyList

public void encodeTableOfContentsIntoPropertyList(NSMutableDictionary propertyList)

Encodes the receiver into propertyList. This method is used to get an ASCII representation of an EOModel in property list format.

See Also: EOModel constructors

entities

public NSArray entities()

Returns an array containing the receiver's entities. Note that this method loads every entity, and thus defeats the benefits of incremental model loading.

See Also: entityNames

entitiesWithSharedObjects

public NSArray entitiesWithSharedObjects()

Returns an array of entities that have objects to load into a shared editing context.

entityForObject

public EOEntity entityForObject(Object anEO)

Returns the entity associated with anEO, whether anEO is an instance of an enterprise object class, an instance of EOGenericRecord, or a fault . Returns null if anEO has no associated entity.

entityNamed

public EOEntity entityNamed(String name)

Returns the entity named name, or null if no such entity exists. Posts an EntityLoadedNotification when the entity is loaded.

See Also: entityNames, entities

entityNames

public NSArray entityNames()

Returns an array containing the names of the EOModel's entities.

See Also: entities, entityNamed

externalModelsReferenced

public NSArray externalModelsReferenced()

Returns an array containing those models that are referenced by this model.

See Also: referencesToProperty

loadAllModelObjects

public void loadAllModelObjects()

Loads any of the receiver's entities, stored procedures, attributes, and relationships that have not yet been loaded.

See Also: attributes (EOEntity), entities, relationships (EOEntity), storedProcedures

modelGroup

public EOModelGroup modelGroup()

Returns the model group of which the receiver is a part.

See Also: setModelGroup

name

public String name()

Returns the receiver's name.

See Also: path, EOModel constructors

path

public String path()

Returns the name of the EOModel file used to create the receiver, or null if the model wasn't initialized from a file.

See Also: name, EOModel constructors

prototypeAttributeNamed

public EOAttribute prototypeAttributeNamed(String attributeName)

Returns the prototype attribute for the given attributeName. It first looks for the prototype in an entity named EOadaptorNamePrototypes (which can be in any model in the receiver's model group). If the prototype isn't found there or if the EOadaptorNamePrototypes entity doesn't exist, it then looks in an entity named EOPrototypes (in any model in the model group). If the search is still unsuccessful, this method finally looks for the prototype in the list of prototypes provided by the adaptor itself.

See Also: availablePrototypeAttributeNames

referencesToProperty

public NSArray referencesToProperty(Object aProperty)

Returns an array of all properties in the receiver that reference aProperty, whether derived attributes, relationships that reference aProperty, and so on. Returns null if aProperty isn't referenced by any of the properties in the model.

See Also: externalModelsReferenced

removeEntity

public void removeEntity(EOEntity name)

Removes the entity with the given name without performing any referential integrity checking.

See Also: addEntity, removeEntityAndReferences

removeEntityAndReferences

public void removeEntityAndReferences(EOEntity entity)

Removes entity and any attributes or relationships in other entities that reference entity.

See Also: removeEntity, addEntity

removeStoredProcedure

public void removeStoredProcedure(EOStoredProcedure storedProcedure)

Removes storedProcedure without checking to see if an entity uses it.

See Also: addStoredProcedure, storedProcedures

setAdaptorName

public void setAdaptorName(String adaptorName)

Sets the name of the receiver's adaptor to adaptorName.

See Also: availableAdaptorNames (EOAdaptor)

setConnectionDictionary

public void setConnectionDictionary(NSDictionary connectionDictionary)

Sets the dictionary containing information used to connect to the database to connectionDictionary. See the EOAdaptor class specification for more information on working with connection dictionaries.

See Also: adaptorWithModel (EOAdaptor)

setModelGroup

public void setModelGroup(EOModelGroup group)

Sets the model group of which the receiver should be a part. Note that you shouldn't change an EOModel's model group after it has been bound to other models in its group.

See Also: modelGroup

setName

public void setName(String name)

Sets the name of the receiver to name.

setUserInfo

public void setUserInfo(NSDictionary dictionary)

Sets the dictionary of auxiliary data, which your application can use for whatever it needs. dictionary can only contain property list data types-that is, String, NSDictionary, NSArray, and NSData.

storedProcedureNamed

public EOStoredProcedure storedProcedureNamed(String name)

Returns the stored procedure named name, or null if the model doesn't contain a stored procedure with the given name.

See Also: storedProcedureNames, storedProcedures

storedProcedureNames

public NSArray storedProcedureNames()

Returns an array containing the names of all of the model's stored procedures.

See Also: storedProcedureNamed, storedProcedures

storedProcedures

public NSArray storedProcedures()

Returns an array containing all of the model's stored procedures. Note that this method loads each of the model's stored procedures, thus defeating the benefits of incremental model loading.

userInfo

public NSDictionary userInfo()

Returns a dictionary of user data. You can use this to store any auxiliary information it needs.

See Also: setUserInfo

writeToFile

public void writeToFile(String path)

Saves the receiver in the directory specified by path. If the file specified by path already exists, a backup copy is first created (using path with a "~" character appended). As a side-effect, this method resets the current path.

Throws an exception on any error which prevents the file from being written.

See Also: path

Notifications

EOModel declares and posts the following notification.

EntityLoadedNotification

Posted after an EOEntity is loaded into memory. The notification contains:

Notification Object	The entity that was loaded.
Userinfo	None