補充一點說明（摘自
http://grails.org/IDE+Integration）：
Groovy Eclipse plugin issues
If you are using the Eclipse Groovy plugin then make sure you disable the preference 'Groovy Compiler Generating Class Files' (Eclipse -> Window -> Preferences -> Groovy Preferences) before importing the Grails project. By default this option is enabled and generates class files for your groovy files, and stores them in the basedir of your Grails project. When these class files are generated, unexpected behaviour is encountered like not able to generate controllers and views for you domain classes.