Unable to load class 'org.codehaus.groovy.runtime.StringGroovyMethods'.

[sirvon]

Got this error upon building the lib:

Error: Unable to load class 'org.codehaus.groovy.runtime.StringGroovyMethods'.
Possible causes for this unexpected error include:<ul><li>Gradle's dependency cache 
may be corrupt (this sometimes occurs after a network connection timeout.)
<a href="syncProject">Re-download dependencies and sync project 
(requires network)</a></li><li>The state of a Gradle build process (daemon) 
may be corrupt. Stopping all Gradle daemons may solve this problem.
<a href="stopGradleDaemons">Stop Gradle build processes (requires restart)
</a></li><li>Your project may be using a third-party plugin which is not 
compatible with the other plugins in the project or the version of Gradle 
requested by the project.</li></ul>In the case of corrupt Gradle processes,
 you can also try closing the IDE and then killing all Java processes.

My internet is connected while building....

thanks

[ShkurtiA]

check this issue: http://stackoverflow.com/questions/28923716/getting-resolve-error-while-importing-project-in-android-studio-unable-to-load
also look build gradle file to have the latest configurations and check
compileSdkVersion 23
buildToolsVersion "23.0.2"

defaultConfig {
    minSdkVersion 9
    targetSdkVersion 23
    versionCode 1
    versionName "1.0"
}