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Sapphire - develop UI without wiring individual widgets Little has changed in the way Java desktop UI is written since the original Java release. Technologies have changed (AWT, Swing, SWT, etc.), but fundamentals remain the same. The developer must choose which widgets to use, how to lay those widgets out, how to store the data being edited and how to synchronize the model with the UI. Even the best developers fall into traps of having UI components talk directly to other UI components rather than through the model. Inordinate amount of time is spent debugging layout and data-binding issues. Sapphire aims to raise UI writing to a higher level of abstraction. The core premise is that the basic building block of UI should not be a widget (text box, label, button, etc.), but rather a property editor. Unlike a widget, a property editor analyzes metadata associated with a given property, renders the appropriate widgets to edit that property and wires up data binding. Data is synchronized, validation is passed from the model to the UI, content assistance is made available, etc. This fundamentally changes the way developers interact with a UI framework. Instead of writing UI by telling the system how to do something, the developer tells the system what they intend to accomplish. When using Sapphire, the developer says "I want to edit LastName property of the person object". When using widget toolkits like SWT, the developer says "create label, create text box, lay them out like so, configure their settings, setup data binding and so on". By the time the developer is done, it is hard to see the original goal in the code that's produced. This results in UI that is inconsistent, brittle and difficult to maintain.

The goal of the Eclipse Scout project is making it easy to build distributed enterprise applications based on the Eclipse platform. It consists of a runtime framework providing transparent service communication between the client and backend part and is shipped with a rich set of common user interface components. The user interface is not built for a particular rendering technology but it encapsulates the core functionality into a headless model. GUI factories are available for rendering the client model into a particular target UI platform. SWT and Swing are supported out of the box and an AJAX GUI factory could be easily added. Developing Scout applications is supported by the Scout SDK, a plug-in set built on top of Eclipse PDE and Eclipse JDT. The Scout SDK works directly on the bare Java resources and assists the development task by providing an augmented view on the underlying Java code. Additionally, it comes with a rich set of wizards and operations for modifying the Scout application project just by editing the underlying Java code. There is no meta-data required. Hence a developer can switch between editing resources using Eclipse's standard editors and leveraging the features of Scout SDK at any point in time. Eclipse Scout can be used to create multi-tier client/server applications, standalone client applications or OSGi-based server applications. Basically, there are three main advantages when choosing Scout as your framework for building such applications. First, the Scout runtime is service oriented by design. Almost every functionality is provided as an OSGi service. Every OSGi bundle may make use of them. Second, Scout provides a rich set of UI elements being uncoupled from a particular GUI technology. And third, building distributed client/server applications is as easy as if both parts would run within the same local JVM.