Having hard time installing GWT plugin. Tried to search for GWT plugins and all I was able to find was GWT Imagebundle which is pretty outdated. Tried File Menu -> configure
Starting from the version 11 it's not possible to add PROJECT_FOLDER/src as it was described in the previously posted (by ctorx) link http://java.dzone.com/tips/gwt-development-intellij-idea. Once we add a source folder it appears as an "Empty library" and doesn't work. This is because IDEA treats it as a folder where should be compiled classes not sources.
But there is a workaround. To fix it we have to hack the module's IML file. Find the following lines in the IML file of your entry point module
<orderEntry type="module-library">
<library>
<CLASSES />
<JAVADOC />
<SOURCES>
<root url="file://$MODULE_DIR$/src/main/java" />
</SOURCES>
</library>
</orderEntry>
and move your path into the CLASSES
tag, so the entire thing looks like the following
<orderEntry type="module-library">
<library>
<CLASSES>
<root url="file://$MODULE_DIR$/src/main/java" />
</CLASSES>
<JAVADOC />
<SOURCES />
</library>
</orderEntry>
There is no GWT support in the Community Edition.