SPARK-1729. Use foreach instead of map for all Options.

Author: harishreedharan

external/flume-sink/src/main/scala/org/apache/spark/flume/sink/SparkAvroCallbackHandler.scala

@@ -59,12 +59,16 @@ private class SparkAvroCallbackHandler(val threads: Int, val channel: Channel,
     val sequenceNumber = seqBase + seqCounter.incrementAndGet()
     val processor = new TransactionProcessor(channel, sequenceNumber,
       n, transactionTimeout, backOffInterval, this)
-    transactionExecutorOpt.map(executor => {
+    transactionExecutorOpt.foreach(executor => {
       executor.submit(processor)
     })
-    processorMap.put(sequenceNumber, processor)
-    // Wait until a batch is available - will be an error if
-    processor.getEventBatch
+    // Wait until a batch is available - will be an error if error message is non-empty
+    val batch = processor.getEventBatch
+    if (batch.getErrorMsg != null && !batch.getErrorMsg.equals("")) {
+      processorMap.put(sequenceNumber, processor)
+    }
+
+    batch
   }
 
   /**
@@ -93,7 +97,7 @@ private class SparkAvroCallbackHandler(val threads: Int, val channel: Channel,
    * @param success Whether the batch was successful or not.
    */
   private def completeTransaction(sequenceNumber: CharSequence, success: Boolean) {
-    Option(removeAndGetProcessor(sequenceNumber)).map(processor => {
+    Option(removeAndGetProcessor(sequenceNumber)).foreach(processor => {
       processor.batchProcessed(success)
     })
   }
@@ -112,7 +116,7 @@ private class SparkAvroCallbackHandler(val threads: Int, val channel: Channel,
    * Shuts down the executor used to process transactions.
    */
   def shutdown() {
-    transactionExecutorOpt.map(executor => {
+    transactionExecutorOpt.foreach(executor => {
       executor.shutdownNow()
     })
   }

external/flume-sink/src/main/scala/org/apache/spark/flume/sink/SparkSink.scala

@@ -84,7 +84,7 @@ class SparkSink extends AbstractSink with Configurable {
     // dependencies which are being excluded in the build. In practice,
     // Netty dependencies are already available on the JVM as Flume would have pulled them in.
     serverOpt = Option(new NettyServer(responder, new InetSocketAddress(hostname, port)))
-    serverOpt.map(server => {
+    serverOpt.foreach(server => {
       LOG.info("Starting Avro server for sink: " + getName)
       server.start()
     })
@@ -93,10 +93,10 @@ class SparkSink extends AbstractSink with Configurable {
 
   override def stop() {
     LOG.info("Stopping Spark Sink: " + getName)
-    handler.map(callbackHandler => {
+    handler.foreach(callbackHandler => {
       callbackHandler.shutdown()
     })
-    serverOpt.map(server => {
+    serverOpt.foreach(server => {
       LOG.info("Stopping Avro Server for sink: " + getName)
       server.close()
       server.join()

external/flume-sink/src/main/scala/org/apache/spark/flume/sink/TransactionProcessor.scala

@@ -106,7 +106,7 @@ private class TransactionProcessor(val channel: Channel, val seqNum: String,
         eventBatch.setErrorMsg("Something went wrong. Channel was " +
           "unable to create a transaction!")
       }
-      txOpt.map(tx => {
+      txOpt.foreach(tx => {
         tx.begin()
         val events = new util.ArrayList[SparkSinkEvent](maxBatchSize)
         val loop = new Breaks
@@ -145,7 +145,7 @@ private class TransactionProcessor(val channel: Channel, val seqNum: String,
         LOG.error("Error while processing transaction.", e)
         eventBatch.setErrorMsg(e.getMessage)
         try {
-          txOpt.map(tx => {
+          txOpt.foreach(tx => {
             rollbackAndClose(tx, close = true)
           })
         } finally {
@@ -163,7 +163,7 @@ private class TransactionProcessor(val channel: Channel, val seqNum: String,
    */
   private def processAckOrNack() {
     batchAckLatch.await(transactionTimeout, TimeUnit.SECONDS)
-    txOpt.map(tx => {
+    txOpt.foreach(tx => {
       if (batchSuccess) {
         try {
           tx.commit()

external/flume/src/main/scala/org/apache/spark/streaming/flume/FlumePollingInputDStream.scala

@@ -151,7 +151,7 @@ private[streaming] class FlumePollingReceiver(
   override def onStop(): Unit = {
     logInfo("Shutting down Flume Polling Receiver")
     receiverExecutor.shutdownNow()
-    connections.map(connection => {
+    connections.foreach(connection => {
       connection.transceiver.close()
     })
     channelFactory.releaseExternalResources()