From 70615947bdac9c4050a00465c426de9e783d0d74 Mon Sep 17 00:00:00 2001
From: Akira Ajisaka <aajisaka@apache.org>
Date: Tue, 26 May 2015 16:16:21 +0900
Subject: [PATCH] HADOOP-8751. NPE in Token.toString() when Token is
 constructed using null identifier. Contributed by kanaka kumar avvaru.

(cherry picked from commit 56996a685e6201cb186cea866d22418289174574)
---
 hadoop-common-project/hadoop-common/CHANGES.txt   |  3 +++
 .../org/apache/hadoop/security/token/Token.java   |  8 ++++----
 .../token/delegation/TestDelegationToken.java     | 15 +++++++++++++++
 3 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index baba53a7638..0091f565786 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -287,6 +287,9 @@ Release 2.8.0 - UNRELEASED
     HADOOP-11927.  Fix "undefined reference to dlopen" error when compiling
     libhadooppipes (Xianyin Xin via Colin P. McCabe)
 
+    HADOOP-8751. NPE in Token.toString() when Token is constructed using null
+    identifier. (kanaka kumar avvaru via aajisaka)
+
 Release 2.7.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/token/Token.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/token/Token.java
index 3944ad12825..539621de359 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/token/Token.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/security/token/Token.java
@@ -70,10 +70,10 @@ public class Token<T extends TokenIdentifier> implements Writable {
    * @param service the service for this token
    */
   public Token(byte[] identifier, byte[] password, Text kind, Text service) {
-    this.identifier = identifier;
-    this.password = password;
-    this.kind = kind;
-    this.service = service;
+    this.identifier = (identifier == null)? new byte[0] : identifier;
+    this.password = (password == null)? new byte[0] : password;
+    this.kind = (kind == null)? new Text() : kind;
+    this.service = (service == null)? new Text() : service;
   }
 
   /**
diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/security/token/delegation/TestDelegationToken.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/security/token/delegation/TestDelegationToken.java
index 239b8414eb3..b41ff152510 100644
--- a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/security/token/delegation/TestDelegationToken.java
+++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/security/token/delegation/TestDelegationToken.java
@@ -44,6 +44,7 @@ import org.apache.hadoop.security.UserGroupInformation.AuthenticationMethod;
 import org.apache.hadoop.security.token.SecretManager;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.security.token.SecretManager.InvalidToken;
+import org.apache.hadoop.security.token.TokenIdentifier;
 import org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSecretManager.DelegationTokenInformation;
 import org.apache.hadoop.util.Daemon;
 import org.apache.hadoop.util.Time;
@@ -539,4 +540,18 @@ public class TestDelegationToken {
     Assert.assertEquals(key1, key2);
     Assert.assertFalse(key2.equals(key3));
   }
+
+  @Test
+  public void testEmptyToken() throws IOException {
+    Token<?> token1 = new Token<TokenIdentifier>();
+
+    Token<?> token2 = new Token<TokenIdentifier>(new byte[0], new byte[0],
+        new Text(), new Text());
+    assertEquals(token1, token2);
+    assertEquals(token1.encodeToUrlString(), token2.encodeToUrlString());
+
+    token2 = new Token<TokenIdentifier>(null, null, null, null);
+    assertEquals(token1, token2);
+    assertEquals(token1.encodeToUrlString(), token2.encodeToUrlString());
+  }
 }