From 566f3d591729afdc5e8504a48dda2b5bf67f37f8 Mon Sep 17 00:00:00 2001
From: Eli Collins <eli@apache.org>
Date: Tue, 21 Aug 2012 00:01:43 +0000
Subject: [PATCH] HDFS-3707. TestFSInputChecker: improper use of skip.
 Contributed by Colin Patrick McCabe

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1375338 13f79535-47bb-0310-9956-ffa450edef68
---
 hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt   |  3 ++
 .../hadoop/hdfs/TestFSInputChecker.java       | 32 +++++++++++++++----
 2 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index b254740bd5b..25687eab074 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -479,6 +479,9 @@ Release 2.0.1-alpha - UNRELEASED
     HDFS-3816. Invalidate work percentage default value should be 0.32f
     instead of 32. (Jing Zhao via suresh)
 
+    HDFS-3707. TestFSInputChecker: improper use of skip.
+    (Colin Patrick McCabe via eli)
+
   BREAKDOWN OF HDFS-3042 SUBTASKS
 
     HDFS-2185. HDFS portion of ZK-based FailoverController (todd)
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFSInputChecker.java b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFSInputChecker.java
index 1faff65727a..2f2c9a4fd6e 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFSInputChecker.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestFSInputChecker.java
@@ -20,7 +20,9 @@ package org.apache.hadoop.hdfs;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
+import java.io.EOFException;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
@@ -159,8 +161,8 @@ public class TestFSInputChecker {
   private void testSkip1(int skippedBytes) 
   throws Exception {
     long oldPos = stm.getPos();
-    long nSkipped = stm.skip(skippedBytes);
-    long newPos = oldPos+nSkipped;
+    IOUtils.skipFully(stm, skippedBytes);
+    long newPos = oldPos + skippedBytes;
     assertEquals(stm.getPos(), newPos);
     stm.readFully(actual);
     checkAndEraseData(actual, (int)newPos, expected, "Read Sanity Test");
@@ -193,13 +195,31 @@ public class TestFSInputChecker {
     testSkip1(FILE_SIZE-1);
     
     stm.seek(0);
-    assertEquals(stm.skip(FILE_SIZE), FILE_SIZE);
-    assertEquals(stm.skip(10), 0);
+    IOUtils.skipFully(stm, FILE_SIZE);
+    try {
+      IOUtils.skipFully(stm, 10);
+      fail("expected to get a PrematureEOFException");
+    } catch (EOFException e) {
+      assertEquals(e.getMessage(), "Premature EOF from inputStream " +
+          "after skipping 0 byte(s).");
+    }
     
     stm.seek(0);
-    assertEquals(stm.skip(FILE_SIZE+10), FILE_SIZE);
+    try {
+      IOUtils.skipFully(stm, FILE_SIZE + 10);
+      fail("expected to get a PrematureEOFException");
+    } catch (EOFException e) {
+      assertEquals(e.getMessage(), "Premature EOF from inputStream " +
+          "after skipping " + FILE_SIZE + " byte(s).");
+    }
     stm.seek(10);
-    assertEquals(stm.skip(FILE_SIZE), FILE_SIZE-10);
+    try {
+      IOUtils.skipFully(stm, FILE_SIZE);
+      fail("expected to get a PrematureEOFException");
+    } catch (EOFException e) {
+      assertEquals(e.getMessage(), "Premature EOF from inputStream " +
+          "after skipping " + (FILE_SIZE - 10) + " byte(s).");
+    }
   }
 
   private void cleanupFile(FileSystem fileSys, Path name) throws IOException {