From c3c2b4d3182bea3b4ee065168844c83f5114edcf Mon Sep 17 00:00:00 2001
From: Steve Loughran <stevel@apache.org>
Date: Mon, 8 Jun 2015 13:02:26 +0100
Subject: [PATCH] HADOOP-12052 IPC client downgrades all exception types to
 IOE, breaks callers trying to use them. (Brahma Reddy Battula via stevel)

---
 hadoop-common-project/hadoop-common/CHANGES.txt           | 3 +++
 .../src/main/java/org/apache/hadoop/ipc/Client.java       | 8 +++++++-
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index 2bdfcdf05b9..6b93e54e420 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -350,6 +350,9 @@ Release 2.8.0 - UNRELEASED
     HADOOP-11924. Tolerate JDK-8047340-related exceptions in
     Shell#isSetSidAvailable preventing class init. (Tsuyoshi Ozawa via gera)
 
+    HADOOP-12052 IPC client downgrades all exception types to IOE, breaks
+    callers trying to use them. (Brahma Reddy Battula via stevel)
+
 Release 2.7.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Client.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Client.java
index 4b4166a2ba5..8062dd60008 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Client.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/ipc/Client.java
@@ -1484,7 +1484,13 @@ public class Client {
           }
         });
       } catch (ExecutionException e) {
-        throw new IOException(e);
+        Throwable cause = e.getCause();
+        // the underlying exception should normally be IOException
+        if (cause instanceof IOException) {
+          throw (IOException) cause;
+        } else {
+          throw new IOException(cause);
+        }
       }
       if (connection.addCall(call)) {
         break;