Added javadocs to ResultTransformer

querydsl-core/src/main/java/com/mysema/query/ResultTransformer.java

@@ -1,6 +1,19 @@
+/*
+ * Copyright (c) 2010 Mysema Ltd.
+ * All rights reserved.
+ *
+ */
 package com.mysema.query;
 
-
+/**
+ * Executes query on a Projectable and transforms results into T. This can be used for example
+ * to group projected columns or to filter out duplicate results.
+ * 
+ * @see com.mysema.query.support.GroupBy
+ * @author sasa
+ *
+ * @param <T> Transformations target type
+ */
 public interface ResultTransformer<T> {
 
     public T transform(Projectable projectable);