Understanding the GWT compiler. The GWT compiler is the fulcrum of GWT.
The entire approach GWT takes, encapsulating browser differences and compiling JavaScript from Java, is made possible by the design and architecture of the compiler. The GWT compiler compiles Java into JavaScript, but it’s important to understand that the compiler doesn’t compile Java the same way javac does. The GWT compiler is really a Java source to JavaScript source translator. The GWT compiler needs hints about the work that it must perform partly because it operates from source. These hints come in the form of the module descriptor, the marker interfaces that denote serializable types, the JavaDoc style annotations used in serializable types for collections, and more.
Running and Debugging - Google Plugin for Eclipse. Creating a Launch Configuration If you created a project using the New Web Application Wizard, a launch configuration will have already been created for you.
It can be found by navigating to the Launch Configuration dialog. Select the Run Configurations... item from the drop-down menu associated with the Run toolbar button: Compile & Debug - Google Web Toolkit. Let's start with the core principle of GWT development: If your GWT application runs in development mode as you expect... and the GWT compiler successfully compiles your application into JavaScript... then your application will work the same way in a web browser as it did in development mode.
The rest of this section introduces development mode (previously called "hosted mode") and production mode (previously called "web mode") and explains how and when to use each. Debugging in Development Mode You will spend most of your development time running your application in development mode, which means that you are interacting with your GWT application without it having been translated into JavaScript. Anytime you edit, run, and debug applications from a Java integrated development environment (IDE), you are working in development mode.
What could cause an UmbrellaException anonymous function on deployed GWT app. UmbrellaException.