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| author | Henri Sara <henri.sara@itmill.com> | 2009-05-11 09:19:03 +0000 |
|---|---|---|
| committer | Henri Sara <henri.sara@itmill.com> | 2009-05-11 09:19:03 +0000 |
| commit | adc8c0ad3573272c236040c3a76005b9e73a5737 (patch) | |
| tree | a3860704dbd5b82dc6af38684b80f8ef79a32722 /src/com/vaadin/data/package.html | |
| parent | 5abc870dda584d0c2fc47fd5eec4ae3de3fa240e (diff) | |
| download | vaadin-framework-adc8c0ad3573272c236040c3a76005b9e73a5737.tar.gz vaadin-framework-adc8c0ad3573272c236040c3a76005b9e73a5737.zip | |
#2904: initial bulk rename "com.itmill.toolkit" -> "com.vaadin"
- com.itmill.toolkit.external not yet fully renamed
svn changeset:7715/svn branch:6.0
Diffstat (limited to 'src/com/vaadin/data/package.html')
| -rw-r--r-- | src/com/vaadin/data/package.html | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/src/com/vaadin/data/package.html b/src/com/vaadin/data/package.html new file mode 100644 index 0000000000..f6e0a2d645 --- /dev/null +++ b/src/com/vaadin/data/package.html @@ -0,0 +1,86 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> +<html> +<head> +</head> + +<body bgcolor="white"> + +<p>Provides interfaces for the data layer which contains classes +for typed data values, data collections, and handlers. A +{@link com.vaadin.data.Property Property} is a simple typed data +value; an {@link com.vaadin.data.Item Item} is a collection of +Properties, each corresponding to a unique identifier; a +{@link com.vaadin.data.Container Container} is a collection of +identified Items with special constraints; a +{@link com.vaadin.data.Buffered Buffered} class is able to track +its changes and to commit or discard them later.</p> + +<h2>Package Specification</h2> + +<p>The package contains a three-tiered structure for typed data objects and +collections of them:</p> + +<center> +<p><a href=Property.html target="classFrame"><img src=doc-files/Property.gif></a></p> +<p><a href=Item.html target="classFrame"><img src=doc-files/Item.gif></a></p> +<p><a href=Container.html target="classFrame"><img src=doc-files/Container_simple.gif></a></p> +</center> + +<ul> + <li>The simplest of these is the + {@link com.vaadin.data.Property 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. + + <li>The second level of the data layer is represented by the + {@link com.vaadin.data.Item Item} which embodies a set of + <i>Properties</i>. Each Property in an Item corresponds to a locally + unique(that is, inside the Item) identifier. + + <li>The third level is called the + {@link com.vaadin.data.Container 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 + <a href=Container.html target="classFrame">class specification</a>. +</ul> + +<p>In addition to these interfaces the package contains the +{@link com.vaadin.data.Buffered 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.</p> + +<p>Provides interfaces for the validation framework. The framework +defines two interfaces; one for classes that need to support external +validation, and another one for the validators themselves.</p> + +<h2>Validation</h2> + +<p>The most important method defined by the +{@link com.vaadin.data.Validatable Validatable} interface is +{@link com.vaadin.data.Validatable#isValid() 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 <code>null</code> value +can be valid value for one validator but invalid for another.<p> + +<p>In addition to <code>isValid()</code>, <code>Validatable</code> defines +methods to add, remove and list validators of a validatable object.</p> + +<p>{@link com.vaadin.data.Validator Validator} defines the +interface for an external validator. These validators may be added to +any <code>Validatable</code> 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 +{@link com.vaadin.data.Validator#validate(Object) validate(Object)} +method.</p> + +<p>In addition to <code>check(Object)</code>, <code>Validator</code> defines +the <code>InvalidValueException</code> which is used to signal that a +checked value is invalid, and the +{@link com.vaadin.data.Validator.Suggestive Suggestive} +subinterface which includes functionality to suggest a valid value for +the validated object.</p><!-- Put @see and @since tags down here. --> + +</body> +</html> |