title: User-mapped section open error in Grails
body: <p>I am trying to build WAR file for a Grails application using IDEA 2017.1.4 on Windows 10.
  I get the following error:</p>
  
  <pre><code>|Compiling 17 GSP files for package [AECommand]
  .Error 
  |WAR packaging error: G:\Dropbox\thePlatform\AETN\aetn-dd-custom-commands\target\classes\gsp\views.properties (The requested operation cannot be performed on a file with a user-mapped section open)
  Process finished with exit code 1
  </code></pre>
  
  <p>The applications runs fine in IDEA and gives me the same error in PowerShell. And it ran and built fine using a terminal "grails war" command on my MacPro, which is currently not available to me.</p>
  
  <p>MacPro and Windows IDEA project use JDK7. </p>
  
  <p>When I try to run the app in PowerShell using JDK8, I get the folloing error which does have "Incompatible JVM?" message in it:</p>
  
  <pre><code>Oct 24, 2017 6:45:17 AM org.springsource.loaded.jvm.JVM copyMethod
  SEVERE: Problems copying method. Incompatible JVM?
  java.lang.reflect.InvocationTargetException
          at sun.reflect.GeneratedMethodAccessor58.invoke(Unknown Source)
          at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
          at java.lang.reflect.Method.invoke(Method.java:497)
          at org.springsource.loaded.jvm.JVM.copyMethod(JVM.java:134)
          at org.springsource.loaded.ri.OriginalClassInvoker.createJavaMethod(OriginalClassInvoker.java:68)
          at org.springsource.loaded.ri.ReflectiveInterceptor.jlClassGetDeclaredMethods(ReflectiveInterceptor.java:151)
          at org.codehaus.groovy.reflection.CachedClass$3$1.run(CachedClass.java:84)
          at java.security.AccessController.doPrivileged(Native Method)
          at org.codehaus.groovy.reflection.CachedClass$3.initValue(CachedClass.java:81)
          at org.codehaus.groovy.reflection.CachedClass$3.initValue(CachedClass.java:79)
          at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:46)
          at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:33)
          at org.codehaus.groovy.reflection.CachedClass.getMethods(CachedClass.java:250)
          at groovy.lang.MetaClassImpl.populateMethods(MetaClassImpl.java:343)
          at groovy.lang.MetaClassImpl.fillMethodIndex(MetaClassImpl.java:293)
          at groovy.lang.MetaClassImpl.initialize(MetaClassImpl.java:3048)
          at groovy.lang.ExpandoMetaClass.initialize(ExpandoMetaClass.java:483)
          at org.codehaus.groovy.reflection.ClassInfo.getMetaClassUnderLock(ClassInfo.java:176)
  </code></pre>