Setting environment variables in Scala JVM

EnvHacker.scala

import java.util.{Collections, Map => JavaMap}
import scala.collection.JavaConverters._

trait EnvHacker {
    /**
     * Portable method for setting env vars on both *nix and Windows.
     * @see http://stackoverflow.com/a/7201825/293064
     */
    def setEnv(newEnv: Map[String, String]): Unit = {
        try {
            val processEnvironmentClass = Class.forName("java.lang.ProcessEnvironment")
            val theEnvironmentField = processEnvironmentClass.getDeclaredField("theEnvironment")
            theEnvironmentField.setAccessible(true)
            val env = theEnvironmentField.get(null).asInstanceOf[JavaMap[String, String]]
            env.putAll(newEnv.asJava)
            val theCaseInsensitiveEnvironmentField = processEnvironmentClass.getDeclaredField("theCaseInsensitiveEnvironment")
            theCaseInsensitiveEnvironmentField.setAccessible(true)
            val cienv = theCaseInsensitiveEnvironmentField.get(null).asInstanceOf[JavaMap[String, String]]
            cienv.putAll(newEnv.asJava)
        } catch {
            case e: NoSuchFieldException =>
                try {
                    val classes = classOf[Collections].getDeclaredClasses
                    val env = System.getenv()
                    for {cl <- classes} {
                        if (cl.getName == "java.util.Collections$UnmodifiableMap") {
                            val field = cl.getDeclaredField("m")
                            field.setAccessible(true)
                            val obj = field.get(env)
                            val map = obj.asInstanceOf[JavaMap[String, String]]
                            map.clear()
                            map.putAll(newEnv.asJava)
                        }
                    }
                } catch {
                    case e2: Exception => e2.printStackTrace()
                }

            case e1: Exception => e1.printStackTrace()
        }
    }
}