refactoring
diff --git a/src/test/java/TestNullableSqls.java b/src/test/java/TestNullableSqls.java
new file mode 100644
index 0000000..a220233
--- /dev/null
+++ b/src/test/java/TestNullableSqls.java
@@ -0,0 +1,5 @@
+/**
+ * @author hanl
+ * @date 30/01/2016
+ */
+public class TestNullableSqls {}