for String type input, JavaStringDateObjectInspector getPrimitiveJava…

…Object should not return null

Signed-off-by: wangxianbin1987 <[email protected]>

json-serde-cdh5-shim/src/main/java/org/openx/data/jsonserde/objectinspector/primitive/JavaStringDateObjectInspector.java

@@ -51,7 +51,7 @@ public DateWritable getPrimitiveWritableObject(Object o) {
     @Override
     public Date getPrimitiveJavaObject(Object o) {
         if(o instanceof String) {
-           parse((String)o);
+           return parse((String)o);
         } else {
             if (o instanceof Date) return (Date) o;
         }