Merge branch 'develop' of https://git-wip-us.apache.org/repos/asf/incubator-nifi into develop

nifi/nifi-external/nifi-spark-receiver/src/main/java/org/apache/nifi/spark/NiFiDataPacket.java

@@ -20,21 +20,20 @@ import java.util.Map;
 
 /**
  * <p>
- * The NiFiDataPacket provides a packaging around a NiFi FlowFile. It wraps both a FlowFile's
+ * The NiFiDataPacket provides a packaging around a NiFi FlowFile. It wraps both
- * content and its attributes so that they can be processed by Spark
+ * a FlowFile's content and its attributes so that they can be processed by
+ * Spark
  * </p>
  */
 public interface NiFiDataPacket {
 
     /**
-	 * Returns the contents of a NiFi FlowFile
+     * @return the contents of a NiFi FlowFile
-	 * @return
      */
     byte[] getContent();
 
     /**
-	 * Returns a Map of attributes that are associated with the NiFi FlowFile
+     * @return a Map of attributes that are associated with the NiFi FlowFile
-	 * @return
      */
     Map<String, String> getAttributes();
 }

nifi/nifi-external/nifi-spark-receiver/src/main/java/org/apache/nifi/spark/NiFiReceiver.java

@@ -31,34 +31,37 @@ import org.apache.nifi.stream.io.StreamUtils;
 import org.apache.spark.storage.StorageLevel;
 import org.apache.spark.streaming.receiver.Receiver;
 
-
 /**
  * <p>
- * The <code>NiFiReceiver</code> is a Reliable Receiver that provides a way to pull data 
+ * The <code>NiFiReceiver</code> is a Reliable Receiver that provides a way to
- * from Apache NiFi so that it can be processed by Spark Streaming. The NiFi Receiver connects 
+ * pull data from Apache NiFi so that it can be processed by Spark Streaming.
- * to NiFi instance provided in the config and requests data from
+ * The NiFi Receiver connects to NiFi instance provided in the config and
- * the OutputPort that is named. In NiFi, when an OutputPort is added to the root process group,
+ * requests data from the OutputPort that is named. In NiFi, when an OutputPort
- * it acts as a queue of data for remote clients. This receiver is then able to pull that data
+ * is added to the root process group, it acts as a queue of data for remote
- * from NiFi reliably.
+ * clients. This receiver is then able to pull that data from NiFi reliably.
  * </p>
  *
  * <p>
- * It is important to note that if pulling data from a NiFi cluster, the URL that should be used
+ * It is important to note that if pulling data from a NiFi cluster, the URL
- * is that of the NiFi Cluster Manager. The Receiver will automatically handle determining the nodes
+ * that should be used is that of the NiFi Cluster Manager. The Receiver will
- * in that cluster and pull from those nodes as appropriate.
+ * automatically handle determining the nodes in that cluster and pull from
+ * those nodes as appropriate.
  * </p>
  *
  * <p>
- * In order to use the NiFiReceiver, you will need to first build a {@link SiteToSiteClientConfig} to provide 
+ * In order to use the NiFiReceiver, you will need to first build a
- * to the constructor. This can be achieved by using the {@link SiteToSiteClient.Builder}.
+ * {@link SiteToSiteClientConfig} to provide to the constructor. This can be
- * Below is an example snippet of driver code to pull data from NiFi that is running on localhost:8080. This
+ * achieved by using the {@link SiteToSiteClient.Builder}. Below is an example
- * example assumes that NiFi exposes and OutputPort on the root group named "Data For Spark".
+ * snippet of driver code to pull data from NiFi that is running on
- * Additionally, it assumes that the data that it will receive from this OutputPort is text
+ * localhost:8080. This example assumes that NiFi exposes and OutputPort on the
- * data, as it will map the byte array received from NiFi to a UTF-8 Encoded string.
+ * root group named "Data For Spark". Additionally, it assumes that the data
+ * that it will receive from this OutputPort is text data, as it will map the
+ * byte array received from NiFi to a UTF-8 Encoded string.
  * </p>
  *
  * <code>
  * <pre>
+ * {@code
  * Pattern SPACE = Pattern.compile(" ");
  *
  * // Build a Site-to-site client config
@@ -106,10 +109,12 @@ import org.apache.spark.streaming.receiver.Receiver;
  * wordCounts.print();
  * ssc.start();
  * ssc.awaitTermination();
+ * }
  * </pre>
  * </code>
  */
 public class NiFiReceiver extends Receiver<NiFiDataPacket> {
+
     private static final long serialVersionUID = 3067274587595578836L;
     private final SiteToSiteClientConfig clientConfig;
 
@@ -131,29 +136,32 @@ public class NiFiReceiver extends Receiver<NiFiDataPacket> {
     }
 
     class ReceiveRunnable implements Runnable {
+
         public ReceiveRunnable() {
         }
 
+        @Override
         public void run() {
             try {
                 final SiteToSiteClient client = new SiteToSiteClient.Builder().fromConfig(clientConfig).build();
                 try {
-					while ( !isStopped() ) {
+                    while (!isStopped()) {
                         final Transaction transaction = client.createTransaction(TransferDirection.RECEIVE);
                         DataPacket dataPacket = transaction.receive();
-						if ( dataPacket == null ) {
+                        if (dataPacket == null) {
                             transaction.confirm();
                             transaction.complete();
 
                             // no data available. Wait a bit and try again
                             try {
                                 Thread.sleep(1000L);
-							} catch (InterruptedException e) {}
+                            } catch (InterruptedException e) {
+                            }
 
                             continue;
                         }
 
-						final List<NiFiDataPacket> dataPackets = new ArrayList<NiFiDataPacket>();
+                        final List<NiFiDataPacket> dataPackets = new ArrayList<>();
                         do {
                             // Read the data into a byte array and wrap it along with the attributes
                             // into a NiFiDataPacket.
@@ -163,10 +171,12 @@ public class NiFiReceiver extends Receiver<NiFiDataPacket> {
 
                             final Map<String, String> attributes = dataPacket.getAttributes();
                             final NiFiDataPacket NiFiDataPacket = new NiFiDataPacket() {
+                                @Override
                                 public byte[] getContent() {
                                     return data;
                                 }
 
+                                @Override
                                 public Map<String, String> getAttributes() {
                                     return attributes;
                                 }
@@ -174,7 +184,7 @@ public class NiFiReceiver extends Receiver<NiFiDataPacket> {
 
                             dataPackets.add(NiFiDataPacket);
                             dataPacket = transaction.receive();
-						} while ( dataPacket != null );
+                        } while (dataPacket != null);
 
                         // Confirm transaction to verify the data
                         transaction.confirm();