XSD SubElement Validations

This is my xsd file:

<xs:schema/>    
    <xs:element name="MainEvent">
    <xs:complexType>
        <xs:sequence>
            <xs:element ref="requestID"/>
            <xs:element name="subEvent" minOccurs="100" maxOccurs="1000">

            </xs:element>
        </xs:sequence>
    </xs:complexType>
</xs:element>

So I want to apply validations using this XSD on my incoming XML file during UN-marshaling . If I convert this XML into MainEvent bean, I am able to apply validations, but there are multiple subEvent.

I want to apply XSD validations on subEvent. How can I do that. Please help me and thanks in advance. I also asked following question related to this but didn't found solution: XSD Validation Using Schema Issue