Handling empty xml tags using java

i have an xml as below.

<stat>
    <Parents>
        <Parent>
            <parentName></parentName>
            <occupation></occupation>
        </Parent>
        <Parent>
            <parentName>Brian</parentName>
            <occupation>Doctor</occupation>
        </Parent>
    </Parents>
     <Parents/>
    <Parents>
        <Parent>
            <parentName></parentName>
            <occupation></occupation开发者_如何学编程>
        </Parent>
        <Parent/>
    </Parents>
</stat>

I need to validate the xml file using java in based on the parents values.When ever the xml file contains empty parents block for e.g: <Parents/> or <Parents> <Parent><parentName></parentName><occupation></occupation></Parent></Parents>.I need to throw an exception saying xml is not valid.How to implement the requirment using either xpath or some approach with out performance issue. Your help appreciated.

---

First, I'd recommend you to take a look on XSD. Using XSD you can define which tags and how many such tags may appear in your XML. Once you are done just validate XML: http://download.oracle.com/javaee/1.4/tutorial/doc/JAXPDOM8.html

d

---

Aside from XSD or RelaxNG schemas (which should allow specifying acceptable models; and empty one not being one of them, can report it), this would be easy to deal with Stax XMLStreamReader (javax.xml.stream.) as well. Read any tutorial, and check for START_ELEMENT/END_ELEMENT pairs (with 'parents' as local name).