GroovyCastException while starting web-app with Gretty

Don’t try to apply from "grettyX-X.plugin" AND define classpath for gretty simultaneously:

// ATTENTION: this script does not work! It contains error!
buildscript {
  repositories {
    jcenter()
  }

  dependencies {
    classpath 'org.gretty:gretty:+'
  }
}

repositories {
  jcenter()
}

apply from: 'https://raw.github.com/gretty-gradle-plugin/gretty/master/pluginScripts/gretty.plugin'

Here the following happens: gradle loads gretty-plugin JARs twice, class-loading gets confused and you get exceptions like GroovyCastException.

Exceptions when using Jacoco code coverage on JDK-8

If you get exceptions when using combination JDK-8 + Gradle 1.1x + Jacoco + Gretty, you are very likely hitting a problem of compatibility between JDK-8 and earlier versions of Jacoco. This is fixed by adding the following to your "build.gradle":

jacoco {
  toolVersion = '0.7.1.201405082137'
}

or, if you don’t want to depend on concrete version of Jacoco and prefer to use the latest available version:

jacoco {
  toolVersion = '+'
}