AttributeHandler - Dealing with Attributes

The attributeHandler class is responsible for managing a single attribute in the a given boObject instance. In a XEO Model, each attribute is of a given type but in the Java API the attributeHandler class is responsible for dealing with all of them (except collection attributes, for that use the bridgeHandler ). This means an attributeHandler class has methods to retrieve and set the value of the attribute with different types (it's up to the developer to know an attribute's type). It's possible, however, to check the attribute model definition for its data type.

In the following sections the most important methods of the API will be presented.

Reading attribute value

These methods allow to read the value of a given attribute (attributes have different data types)

Method	Description	Parameters	Return Type
getValueBoolean	Returns the value of the attribute as a boolean (throws exception if value cannot be converted to boolean)	-	boolean
getValueString	Returns the value of the attribute as a string (throws exception if value cannot be converted to string)	-	String
getValueLong	Returns the value of the attribute as a long (throws exception if value cannot be converted to long)	-	Long
getValueDouble	Returns the value of the attribute as a double (throws exception if value cannot be converted to double)	-	Double
getValueIFile	Returns the value of the attribute as a IFile (throws exception if value cannot be converted to Ifile)	-	IFile
getValueDate	Returns the value of the attribute as a Date (throws exception if value cannot be converted to Date)	-	Date
getValueObject	Returns the value of the attribute as a raw java object	-	Object

Setting the attribute value

These methods allow to set the value of a given attribute

Method name	Description	Parameters	Return type
setValueBoolean	Set the value of the attribute as a boolean	Boolean value	void
setValueString	Set the value of the attribute as a string	String value	void
setValueLong	Set the value of the attribute as a long	Long value	void
setValueDouble	Set the value of the attribute as a double	Double value	void
setValueDate	Set the value of the attribute as a date	Date value	void
setValueIFile	Set the value of the attribute as an ifile	IFile value	void
setValueObject	Set the value of the attribute as a raw java object	Object value	void

Definition

The methods allow to retrieve handlers or values that are related to the XEO Model definition of the attribute

Method Name	Description	Parameters	Return type	Notes
getDefAttribute	Retrieves the attribute definition handler for the current attribute	-	boDefAttribute
getName	Retrieves the name of the attribute (not the label) in the definition	-	String

Attribute Behavior

These methods allow to query the attribute handler for the result of certain behaviors.

Method name	Description	Parameters	Return type	Notes
hiddenWhen	Returns whether the attribute should be hidden (evaluates user code defined in the object model)	-	boolean
disableWhen	Returns whether the attribute should be disabled (evaluates user code defined in the object model)	-	boolean
required	Returns whether the attribute should be required (evaluates user code defined in the object model)	-	boolean
valid	Returns whether the attribute's value is valid (evaluates user code defined in the object model)	-	boolean
haveDefaultValue	Returns whether the attribute has a default value or not	-	boolean
defaultValue	Returns the attribute's default value (evaluates user code defined in the object model)	-	String	The default value for an attribute must always be a string which is convertible to the attribute's native format (example, the default value for a attribute of type date must be a string which can be parsed as a java.util.Date)
isDisabled	Returns whether the attribute is disabled or not	-	boolean
setDisabled	Sets the attribute as disabled	-	void
setInvalid	Marks the attribute has invalid	-	void

Topic revision: r4 - 2011-04-04 - NicolauGrosskopf

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