Move REPL classes to separate module.

core/src/main/scala/spark/ClosureCleaner.scala

@@ -64,10 +64,19 @@ object ClosureCleaner extends Logging {
       accessedFields(cls) = Set[String]()
     for (cls <- func.getClass :: innerClasses)
       getClassReader(cls).accept(new FieldAccessFinder(accessedFields), 0)
-    
+
+    val isInterpNull = {
+      try {
+        val klass = Class.forName("spark.repl.Main")
+        klass.getMethod("interp").invoke(null) == null
+      } catch {
+        case _: ClassNotFoundException => true
+      }
+    }
+
     var outer: AnyRef = null
     for ((cls, obj) <- (outerClasses zip outerObjects).reverse) {
-      outer = instantiateClass(cls, outer);
+      outer = instantiateClass(cls, outer, isInterpNull);
       for (fieldName <- accessedFields(cls)) {
         val field = cls.getDeclaredField(fieldName)
         field.setAccessible(true)
@@ -85,8 +94,8 @@ object ClosureCleaner extends Logging {
     }
   }
   
-  private def instantiateClass(cls: Class[_], outer: AnyRef): AnyRef = {
-    if (spark.repl.Main.interp == null) {
+  private def instantiateClass(cls: Class[_], outer: AnyRef, isInterpNull: Boolean): AnyRef = {
+    if (isInterpNull) {
       // This is a bona fide closure class, whose constructor has no effects
       // other than to set its fields, so use its constructor
       val cons = cls.getConstructors()(0)

core/src/main/scala/spark/Executor.scala

@@ -105,7 +105,15 @@ class Executor extends mesos.Executor with Logging {
     val classUri = System.getProperty("spark.repl.class.uri")
     if (classUri != null) {
       logInfo("Using REPL class URI: " + classUri)
-      loader = new repl.ExecutorClassLoader(classUri, loader)
+      loader = {
+        try {
+          val klass = Class.forName("spark.repl.ExecutorClassLoader").asInstanceOf[Class[_ <: ClassLoader]]
+          val constructor = klass.getConstructor(classUri.getClass, loader.getClass)
+          constructor.newInstance(classUri, loader)
+        } catch {
+          case _: ClassNotFoundException => loader
+        }
+      }
     }
 
     return loader

project/build/SparkProject.scala

@@ -10,6 +10,8 @@ class SparkProject(info: ProjectInfo) extends ParentProject(info) with IdeaProje
 
   lazy val core = project("core", "Spark Core", new CoreProject(_))
 
+  lazy val repl = project("repl", "Spark REPL", new ReplProject(_), core)
+
   lazy val examples = project("examples", "Spark Examples", new ExamplesProject(_), core)
 
   lazy val bagel = project("bagel", "Bagel", new BagelProject(_), core)
@@ -34,6 +36,10 @@ class SparkProject(info: ProjectInfo) extends ParentProject(info) with IdeaProje
     val jetty = jettyWebapp
   }
 
+  class ReplProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject with DepJar with XmlTestReport {
+    val jetty = jettyWebapp
+  }
+
   class ExamplesProject(info: ProjectInfo) extends DefaultProject(info) with BaseProject {
     val colt = "colt" % "colt" % "1.2.0"
   }