diff -urN mysql-connector-java-5.1.40/src/com/mysql/jdbc/ResultSetImpl.java mysql-connector-java-5.1.40.new/src/com/mysql/jdbc/ResultSetImpl.java
--- mysql-connector-java-5.1.40/src/com/mysql/jdbc/ResultSetImpl.java	2016-09-25 01:35:01.000000000 +0700
+++ mysql-connector-java-5.1.40.new/src/com/mysql/jdbc/ResultSetImpl.java	2016-10-13 19:05:19.022284134 +0700
@@ -4932,6 +4932,13 @@
 
         Object value = this.thisRow.getColumnValue(columnIndex - 1);
 
+        if (value == null) {
+            this.wasNullFlag = true;
+            return 0;
+        }
+
+        this.wasNullFlag = false;
+        
         if (this.fields[columnIndex - 1].isSingleBit() || ((byte[]) value).length == 1) {
             return ((byte[]) value)[0];
         }