grails - GStringImpl cannot be cast to java.lang.String -

I got an error in using grails and spring security. Someone has such a problem.

  error. Exception in thread "Thread-15" error. Java.lang.ClassCastException: org.codehaus.groovy.runtime.GStringImpl can not be entered in java.lang.String error. Org.codehaus.groovy.grails.project.compiler.GrailsProjectWatcher.run (GrailsProjectWatcher.java:114)  

and

  java.lang.IllegalArgumentException : Have you generated all the sections (user, etc.)? User_name ' 

role ...) What does your order look like? This way grails s2-quickstart com.testapp user role ? Check your configuration and see it in this tutorial.

Actually this error means that you use a GString like "$ {my_var}" and some classes are expected to be string. It can not be inserted automatically. If you have such a code, you have to change it in the string: "$ {my_var}". ToString () .