use parens when calling method with side-effects

core/src/main/scala/spark/SparkEnv.scala

@@ -59,7 +59,7 @@ class SparkEnv (
 
   def createPythonWorker(pythonExec: String, envVars: Map[String, String]): java.net.Socket = {
     synchronized {
-      pythonWorkers.getOrElseUpdate((pythonExec, envVars), new PythonWorkerFactory(pythonExec, envVars)).create
+      pythonWorkers.getOrElseUpdate((pythonExec, envVars), new PythonWorkerFactory(pythonExec, envVars)).create()
     }
   }
 

core/src/main/scala/spark/api/python/PythonRDD.scala

@@ -116,12 +116,12 @@ private[spark] class PythonRDD[T: ClassManifest](
               // We've finished the data section of the output, but we can still
               // read some accumulator updates; let's do that, breaking when we
               // get a negative length record.
-              var len2 = stream.readInt
+              var len2 = stream.readInt()
               while (len2 >= 0) {
                 val update = new Array[Byte](len2)
                 stream.readFully(update)
                 accumulator += Collections.singletonList(update)
-                len2 = stream.readInt
+                len2 = stream.readInt()
               }
               new Array[Byte](0)
           }

core/src/main/scala/spark/api/python/PythonWorkerFactory.scala

@@ -16,7 +16,7 @@ private[spark] class PythonWorkerFactory(pythonExec: String, envVars: Map[String
   def create(): Socket = {
     synchronized {
       // Start the daemon if it hasn't been started
-      startDaemon
+      startDaemon()
 
       // Attempt to connect, restart and retry once if it fails
       try {
@@ -24,8 +24,8 @@ private[spark] class PythonWorkerFactory(pythonExec: String, envVars: Map[String
       } catch {
         case exc: SocketException => {
           logWarning("Python daemon unexpectedly quit, attempting to restart")
-          stopDaemon
-          startDaemon
+          stopDaemon()
+          startDaemon()
           new Socket(daemonHost, daemonPort)
         }
         case e => throw e
@@ -34,7 +34,7 @@ private[spark] class PythonWorkerFactory(pythonExec: String, envVars: Map[String
   }
 
   def stop() {
-    stopDaemon
+    stopDaemon()
   }
 
   private def startDaemon() {
@@ -51,7 +51,7 @@ private[spark] class PythonWorkerFactory(pythonExec: String, envVars: Map[String
         val workerEnv = pb.environment()
         workerEnv.putAll(envVars)
         daemon = pb.start()
-        daemonPort = new DataInputStream(daemon.getInputStream).readInt
+        daemonPort = new DataInputStream(daemon.getInputStream).readInt()
 
         // Redirect the stderr to ours
         new Thread("stderr reader for " + pythonExec) {
@@ -71,7 +71,7 @@ private[spark] class PythonWorkerFactory(pythonExec: String, envVars: Map[String
         }.start()
       } catch {
         case e => {
-          stopDaemon
+          stopDaemon()
           throw e
         }
       }
@@ -85,7 +85,7 @@ private[spark] class PythonWorkerFactory(pythonExec: String, envVars: Map[String
     synchronized {
       // Request shutdown of existing daemon by sending SIGTERM
       if (daemon != null) {
-        daemon.destroy
+        daemon.destroy()
       }
 
       daemon = null