SQOOP-2282: Add validation check for --hive-import and --append

(Abraham Elmahrek via Jarek Jarcec Cecho)
diff --git a/src/java/org/apache/sqoop/tool/BaseSqoopTool.java b/src/java/org/apache/sqoop/tool/BaseSqoopTool.java
index 058e81d..c97bb58 100644
--- a/src/java/org/apache/sqoop/tool/BaseSqoopTool.java
+++ b/src/java/org/apache/sqoop/tool/BaseSqoopTool.java
@@ -1396,6 +1396,12 @@
         + "importing into SequenceFile format.");
     }
 
+    if (options.doHiveImport()
+        && options.isAppendMode()) {
+      throw new InvalidOptionsException("Append mode for hive imports is not "
+          + " yet supported. Please remove the parameter --append-mode");
+    }
+
     // Many users are reporting issues when they are trying to import data
     // directly into hive warehouse. This should prevent users from doing
     // so in case of a default location.