From 19a7e94ee47f81557f0db6fb76bdf6bc49944dd0 Mon Sep 17 00:00:00 2001
From: Lei Xu <lei@apache.org>
Date: Fri, 28 Apr 2017 17:06:14 -0700
Subject: [PATCH] HDFS-11718. DFSStripedOutputStream hsync/hflush should not
 throw UnsupportedOperationException. (Manoj Govindassamy via lei)

Change-Id: I4cc226b80c64a0d900a3b1ce71e51f051cd29c22
---
 .../hadoop/hdfs/DFSStripedOutputStream.java   |  4 +--
 .../hdfs/TestDFSStripedOutputStream.java      | 29 ++++++++++++++++++-
 2 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSStripedOutputStream.java b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSStripedOutputStream.java
index 22b30e9306..3dd07f72e0 100644
--- a/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSStripedOutputStream.java
+++ b/hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/DFSStripedOutputStream.java
@@ -783,12 +783,12 @@ public class DFSStripedOutputStream extends DFSOutputStream {
 
   @Override
   public void hflush() {
-    throw new UnsupportedOperationException();
+    // not supported yet
   }
 
   @Override
   public void hsync() {
-    throw new UnsupportedOperationException();
+    // not supported yet
   }
 
   @Override
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSStripedOutputStream.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSStripedOutputStream.java
index 14825ca41b..70309c95fe 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSStripedOutputStream.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSStripedOutputStream.java
@@ -17,15 +17,21 @@
  */
 package org.apache.hadoop.hdfs;
 
+import static org.apache.hadoop.fs.contract.ContractTestUtils.fail;
+
+import java.io.ByteArrayInputStream;
 import java.io.IOException;
+import java.io.InputStream;
 import java.util.ArrayList;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.fs.FSDataOutputStream;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hdfs.protocol.DatanodeInfo;
 import org.apache.hadoop.hdfs.protocol.ErasureCodingPolicy;
+import org.apache.hadoop.io.IOUtils;
 import org.apache.hadoop.io.erasurecode.CodecUtil;
 import org.apache.hadoop.io.erasurecode.ErasureCodeNative;
 import org.apache.hadoop.io.erasurecode.rawcoder.NativeRSRawErasureCoderFactory;
@@ -170,7 +176,6 @@ public class TestDFSStripedOutputStream {
         blockSize * dataBlocks + cellSize+ 123);
   }
 
-
   @Test
   public void testFileMoreThanABlockGroup3() throws Exception {
     testOneFile("/MoreThanABlockGroup3",
@@ -178,6 +183,28 @@ public class TestDFSStripedOutputStream {
         + cellSize + 123);
   }
 
+  /**
+   * {@link DFSStripedOutputStream} doesn't support hflush() or hsync() yet.
+   * This test is to make sure that DFSStripedOutputStream doesn't throw any
+   * {@link UnsupportedOperationException} on hflush() or hsync() so as to
+   * comply with output stream spec.
+   *
+   * @throws Exception
+   */
+  @Test
+  public void testStreamFlush() throws Exception {
+    final byte[] bytes = StripedFileTestUtil.generateBytes(blockSize *
+        dataBlocks * 3 + cellSize * dataBlocks + cellSize + 123);
+    try (FSDataOutputStream os = fs.create(new Path("/ec-file-1"))) {
+      InputStream is = new ByteArrayInputStream(bytes);
+      IOUtils.copyBytes(is, os, bytes.length);
+      os.hflush();
+      os.hsync();
+    } catch (Exception e) {
+      fail("hflush()/hsync() on striped file output stream failed!", e);
+    }
+  }
+
   private void testOneFile(String src, int writeBytes) throws Exception {
     src += "_" + writeBytes;
     Path testPath = new Path(src);