I bet you have never get it to the stage of validating anything at all. And what you observe has nothing to do with the schema. It has everything to do with your class com.pack1.SampleDTO where there is a method isHasNext() returning a boolean. That's all. xsd data typing has no bearing on the problem not to say conversion of anything. You can put truce, ecurt, true or anything there and the result would be the same.
 In the case of further development to the stage of validating, suffice it to mention that the schema (xsd) is invalid? It can never get pass the loading stage. What is the problem? I leave it to your own discovering.