Package org.millstone.base.data

Provides interfaces for the MillStone data layer which contains classes for typed data values, data collections, and handlers.

See:
Description

Interface Summary

Buffered	Defines the interface to commit and discard changes to an object, supporting read-through and write-through modes.
BufferedValidatable	This interface defines the combination of Validatable and Buffered interfaces.
Container	A specialized set of identified Items.
Container.Editor	Interface implemented by the editor classes supporting editing the Container.
Container.Hierarchical	Interface for Container classes whose Items can be arranged hierarchically.
Container.Indexed	Interface for Container classes whose Items can be indexed.
Container.ItemSetChangeEvent	An Event object specifying the Container whose Item set has changed.
Container.ItemSetChangeListener	Container Item set change listener interface.
Container.ItemSetChangeNotifier	The interface for adding and removing ItemSetChangeEvent listeners.
Container.Ordered	Interface for Container classes whose Items can be traversed in order.
Container.PropertySetChangeEvent	An Event object specifying the Container whose Property set has changed.
Container.PropertySetChangeListener	The listener interface for receiving PropertySetChangeEvent objects.
Container.PropertySetChangeNotifier	The interface for adding and removing PropertySetChangeEvent listeners.
Container.Viewer	Interface implemented by viewer classes capable of using a Container as a data source.
Item	Provides a mechanism for handling a set of Properties, each associated to a locally unique identifier.
Item.Editor	Interface implemented by the editor classes capable of editing the Item.
Item.PropertySetChangeEvent	An Event object specifying the Item whose contents has been changed through the Property.Managed interface.
Item.PropertySetChangeListener	The listener interface for receiving PropertySetChangeEvent objects.
Item.PropertySetChangeNotifier	The interface for adding and removing PropertySetChangeEvent listeners.
Item.Viewer	Interface implemented by viewer classes capable of using an Item as a data source.
Property	Property is a simple data object that contains one typed value.
Property.Editor	Interface implemented by the editor classes capable of editing the Property.
Property.ReadOnlyStatusChangeEvent	An Event object specifying the Property whose read-only status has been changed.
Property.ReadOnlyStatusChangeListener	The listener interface for receiving ReadOnlyStatusChangeEvent objects.
Property.ReadOnlyStatusChangeNotifier	The interface for adding and removing ReadOnlyStatusChangeEvent listeners.
Property.ValueChangeEvent	An Event object specifying the Property whose value has been changed.
Property.ValueChangeListener	The listener interface for receiving ValueChangeEvent objects.
Property.ValueChangeNotifier	The interface for adding and removing ValueChangeEvent listeners.
Property.Viewer	Interface implemented by the viewer classes capable of using a Property as a data source.
Validatable	Interface for validatable objects.
Validator	Object validator interface.
Validator.Suggestive	Adds the proposing functionality to a Validator.

Exception Summary

Buffered.SourceException	An exception that signals that one or more exceptions occurred while a buffered object tried to access its data source.
Property.ConversionException	An exception that signals that the value passed to the setValue() method couldn't be converted to the native type of the Property.
Property.ReadOnlyException	Exception object that signals that a requested Property modification failed because it's in read-only mode.
Validator.InvalidValueException	Invalid value exception can be thrown by Validator when a given value is not valid.

Package org.millstone.base.data Description

Provides interfaces for the MillStone data layer which contains classes for typed data values, data collections, and handlers. A Property is a simple typed data value; an Item is a collection of Properties, each corresponding to a unique identifier; a Container is a collection of identified Items with special constraints; a Buffered class is able to track its changes and to commit or discard them later.

Package Specification

The package contains a three-tiered structure for typed data objects and collections of them:

• The simplest of these is the Property which represents a single typed data value. A Property may be read-only in which case attempts to modify its contents will throw an exception.
• The second level of the data layer is represented by the Item which embodies a set of Properties. Each Property in an Item corresponds to a locally unique(that is, inside the Item) identifier.
• The third level is called the Container which can be visualized as a set of Items, each corresponding to a locally unique identifier. Note that the Container imposes a few restrictions on the data stored in it, see further documentation in the class specification.

In addition to these interfaces the package contains the Buffered interface, which defines the methods to make an object buffered, that is, track the changes to an object and allow committing or discarding them at a later time.

Provides interfaces for the MillStone validation framework. The framework defines two interfaces; one for classes that need to support external validation, and another one for the validators themselves.

Validation

The most important method defined by the Validatable interface is isValid(). It asks all registered validators to verify if the object's value is valid or not. Note that it depends on the validators registered for a object which values are valid and which are not. For example, a null value can be valid value for one validator but invalid for another.

In addition to isValid(), Validatable defines methods to add, remove and list validators of a validatable object.

Validator defines the interface for an external validator. These validators may be added to any Validatable object, and their task is to check, when requested, that the object which they are attached to contains a valid value. The actual validation logic is hidden in the validate(Object) method.

In addition to check(Object), Validator defines the InvalidValueException which is used to signal that a checked value is invalid, and the Suggestive subinterface which includes functionality to suggest a valid value for the validated object.