fix checkstyle problem.

Author: hfutatzhanghb

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSClientFaultInjector.java

@@ -72,6 +72,6 @@ public void delayWhenRenewLeaseTimeout() {}
   public void onCreateBlockReader(LocatedBlock block, int chunkIndex, long offset, long length) {}
 
   public void failCreateBlockReader() throws InvalidBlockTokenException {}
-  
+
   public void failCreateBlockReader(int curRetryCounts) throws IOException {}
 }

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSStripedInputStream.java

@@ -777,7 +777,9 @@ public void failCreateBlockReader(int curRetryCounts) throws IOException {
       byte[] readBuf = new byte[6 * 1024 * 1024];
       try (FSDataInputStream fsdis = dfs.open(
           new Path(testBaseDir + Path.SEPARATOR + testfileName))) {
-        while ((fsdis.read(readBuf)) > 0) {}
+        while ((fsdis.read(readBuf)) > 0) {
+          // Do nothing.
+        }
       }
       assertTrue(dfs.delete(new Path(testBaseDir + Path.SEPARATOR + testfileName), true));
     } finally {