Updating dataset reader examples to use for-each.

Author: rdblue

dataset/src/main/java/com/cloudera/cdk/examples/data/ReadHCatalogUserDatasetGeneric.java

@@ -42,8 +42,7 @@ public int run(String[] args) throws Exception {
     DatasetReader<GenericRecord> reader = users.getReader();
     try {
       reader.open();
-      while (reader.hasNext()) {
-        GenericRecord user = reader.read();
+      for (GenericRecord user : reader) {
         System.out.println(user);
       }
     } finally {

dataset/src/main/java/com/cloudera/cdk/examples/data/ReadProductDatasetPojo.java

@@ -43,8 +43,7 @@ public int run(String[] args) throws Exception {
     DatasetReader<Product> reader = products.getReader();
     try {
       reader.open();
-      while (reader.hasNext()) {
-        Product product = reader.read();
+      for (Product product : reader) {
         System.out.println(product);
       }
     } finally {

dataset/src/main/java/com/cloudera/cdk/examples/data/ReadUserDatasetGeneric.java

@@ -44,8 +44,7 @@ public int run(String[] args) throws Exception {
     DatasetReader<GenericRecord> reader = users.getReader();
     try {
       reader.open();
-      while (reader.hasNext()) {
-        GenericRecord user = reader.read();
+      for (GenericRecord user : reader) {
         System.out.println(user);
       }
     } finally {

dataset/src/main/java/com/cloudera/cdk/examples/data/ReadUserDatasetGenericOnePartition.java

@@ -54,8 +54,7 @@ public int run(String[] args) throws Exception {
     DatasetReader<GenericRecord> reader = partition.getReader();
     try {
       reader.open();
-      while (reader.hasNext()) {
-        GenericRecord user = reader.read();
+      for (GenericRecord user : reader) {
         System.out.println(user);
       }
     } finally {