![Google Web Toolkit (GWT) @ deployment time @ development time <html> [...] <script type="text/javascript"> [...] xmlhttp.open("POST", url, true); xmlhttp.onreadystatechange = function(func) { if (xmlhttp.readyState == 4) { [...] } } xmlhttp.setRequestHeader('MessageType', 'CALL'); xmlhttp.setRequestHeader('Content-Type', 'text/xml'); </script> <body>[...]</body> </html> JAVA/eclipse javascript Hosted mode JVM IDE Compile to JAVA bytecode Compile to Javascript](https://image.slidesharecdn.com/gwtpresentation-090518093225-phpapp02/85/Gwt-Presentation1-13-320.jpg)
Gwt Presentation1
- 1. GWT A 'new' way to program dynamic web applications - Usman - Pavan - Rajakumar
- 2. Overview of AJAX development Problems with AJAX What is GWT ? Why GWT ? Sample application User Interface with GWT RPC Cons Agenda
- 3. Classic web application model (synchronous)
- 4. Ajax web application model (asynchronous)
- 5. Asynchronous JavaScript and XML (AJAX) Server - side Client – side Javascript JAVA + no page transition, no blocking No IDE Debugging is difficult weakly typed + eclipse: debugging, easy development good IDE’s Debugging is easy strongly typed
- 6. AJAX Asynchronous JavaScript and XML. Clientside javascript to asynchronously fetch the data Using the DOM API dynamically modify the page Based on javascript,html,xml,css.xhtml,DOM. Web browser UI to be more interactive and to respond quickly to inputs
- 7. Drawbacks Multiple languages and framework across stack Mixing the js,jsp,xml,java leads maintenance problem Less modularization Less reusable code Breaks MVC principle. Complicated debugging and testing with different browsers. Browsers back button and history maintains problem OOPS
- 8. What is GWT ? A FrameWork for building highly perfomant, Ajax enabled , Javascript front-end web applications . Provides Java-to-javaScirpt Compiler . Allow to use the java development tools like netbeans and eclipse. Shell to test and debug modules without compilation Simple asynchronous browser-to-server RPC
- 9. Why GWT ? Rich user Interface Open source No need to learn Javascript language No need to learn DOM Api( use java Api) No plugIns required in client side Junit integration
- 10. Why GWT ? (Cont ... ) OOPS Asynchronous Calls To share load between client and server Keeping only insensitive data on client side Not for validation but for the better and rich user interface.
- 12. Modes of Running Gwt application Gwt Application can run in two modes . Host Mode Hosted Mode is a 'simulated' mode Run entirely from Eclipse using the GWT Shell. * Consists of a customized Tomcat Web container. * Makes debugging easier . Web Mode Run as pure JavaScript and HTML,compiled from your original Java source code with the GWT
- 13. Google Web Toolkit (GWT) @ deployment time @ development time <html> [...] <script type="text/javascript"> [...] xmlhttp.open("POST", url, true); xmlhttp.onreadystatechange = function(func) { if (xmlhttp.readyState == 4) { [...] } } xmlhttp.setRequestHeader('MessageType', 'CALL'); xmlhttp.setRequestHeader('Content-Type', 'text/xml'); </script> <body>[...]</body> </html> JAVA/eclipse javascript Hosted mode JVM IDE Compile to JAVA bytecode Compile to Javascript
- 14. GWT: project structure Package Purpose it/sella/gwt/ The project root package contains module XML files it/sella/gwt/client/ Client-side source files and subpackages it/sella/gwt/server/ Server-side code and subpackages it/sella/gwt/public/ Static resources that can be served publicly
- 15. GWT Modules *.gwt.xml Jsp,Html, ... Entry point class (java class) Css , Images ,other xmls … External java script file
- 17. GWT-RPC These are Asynchronous Calls. A framework used to exchange java objects . Based on the java servlet architecture . GWT handle the serialization of java objects. GWT-RPC services are not same as web services . .
- 19. Corns of GWT Browser compatibility pretty good but issues with some browsers. Although java to javascript convertion takes place, not all features of java can be implemented .eg multi threading,Calender etc Gwt generated javascript and html are very difficult to understand . Layouts,panels and some widgets have bugs .
- 20. Corns of GWT ( Cont... ) The appearance of the application depends on the browser. Take long time to load and heavily uses the client resources.
- 21. Reference Documentation & Tutorial : http://code.google.com/webtoolkit/ http://code.google.com/webtoolkit/tutorials/1.6/index.html Libraries http://gwt-ext.com/ http://extjs.com/products/gxt/ Showcase http://gwt.google.com/samples/Showcase/Showcase.html http://www.gwt-ext.com/demo/#credits