Creating a GWT module as a Library

GWT modules are meant to enable modularisation for Google Web Toolkit (GWT).

I like to develop my applications in mutiple eclipse projects by linking their source folders.

So, I create one project for the actual application and one for the library or whatever that the application uses.

First, I created the projects using the eclipse GWT plugin wizard.

I renamed the “gwt.xml” file in the library project to “webeditor.gwt.xml”. Then I changed the module name:

<module rename-to=’de.linnk.webeditor.webeditor’>

Further, I added the statement:

<source path=”client”/>

Then I put a class “Test” in the client source folder.

The I rennamed the source folder from “src” to “webeditor”.

In the project for the application, I linked the “webeditor” source folder and I added the following line in the “gwt.xml” file:

<inherits name=’de.linnk.webeditor.webeditor’/>

Now I can use the class “Test” in my application project – without having to compile the library application – its automatically compiled when the application project is compiled.

NOTE: I don’t know why I have to leave the “entry-point” declaration in my library’s gwt.xml? Doesn’t compile without that …

Running Google Web Application Project on your tomcat server

I was wondering how I could run a Google Web Application Project created with the wizard in eclipse (part of the google eclipse plugin) on my own tomcat server.

Well, its fairly simple.

First it should be noted that when creating the project with the wizard you should deselect the google app engine sdk. You can still run your projects on google app engine, so you just make sure that you do not use any app engine specific functionality (what I would not recommend anyway to keep your projects portable).

If this prerequisite is given, you can you can just select the project you have created (the root folder) and click Google’s red box GWT button “GWT compile project”.

Then you can go to the project folder in the eclipse workspace. One of the folders created is “war”. Create a new folder in your tomcat webapps folder and name it according to your project name eg “myproject”. Now you can copy all the contents from “war” to “myproject”.

Start tomcat and volia the application should be running.

(I am not too sure whether there might be issues in more complex projects given that google uses jetty for the debug mode that can be strated directly from eclipse)