Add doc + refactor + fix formatting

java/RocksDBSample.java

@@ -141,9 +141,9 @@ public class RocksDBSample {
         System.out.println("Failed in call to geHistogramData()");
         assert(false); //Should never reach here.
       }
-      
+
       Iterator iterator = db.iterator();
-      
+
       boolean seekToFirstPassed = false;
       for (iterator.seekToFirst(); iterator.isValid(); iterator.next()) {
         iterator.status();
@@ -154,7 +154,7 @@ public class RocksDBSample {
       if(seekToFirstPassed) {
         System.out.println("iterator seekToFirst tests passed.");
       }
-      
+
       boolean seekToLastPassed = false;
       for (iterator.seekToLast(); iterator.isValid(); iterator.prev()) {
         iterator.status();
@@ -162,18 +162,18 @@ public class RocksDBSample {
         assert(iterator.value() != null);
         seekToLastPassed = true;
       }
-      
+
       if(seekToLastPassed) {
         System.out.println("iterator seekToLastPassed tests passed.");
       }
-      
+
       iterator.seekToFirst();
       iterator.seek(iterator.key());
       assert(iterator.key() != null);
       assert(iterator.value() != null);
-      
+
       System.out.println("iterator seek test passed.");
-      
+
       iterator.close();
       System.out.println("iterator tests passed.");
     } catch (RocksDBException e) {