Need help in validating with the existing XML and existing XSD:
---------------------------------------------------------------

These are the entities used:
----------------------------
XSD FILE (mainInfo.xsd):
========================

    code:

    
    <?xml version="1.0" encoding="UTF-8"?>
    <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:abc="http://somesite.com/schemas/BaseDataTypes" targetNamespace="http://somesite.com/schemas/BaseDataTypes">
        <xsd:include schemaLocation="http://somesite.com/schemas/BaseDataTypes.xsd"/>
    
        <xsd:element name="mainDetail">
            <xsd:complexType>
                <xsd:sequence>
                    <xsd:element name="City" type="abc:String30DataType"/>
                    <xsd:element name="State" type="abc:String30DataType"/>
                </xsd:sequence>
            </xsd:complexType>
        </xsd:element>
    

        <xsd:element name="mainHeader">
            <xsd:complexType>
                <xsd:sequence>
                    <xsd:element ref="abc:TotalRecords"/>
                </xsd:sequence>
            </xsd:complexType>
        </xsd:element>
    

        <xsd:element name="mainTag">
            <xsd:complexType>
                <xsd:sequence>
                    <xsd:element ref="abc:mainHeader"/>
                    <xsd:element ref="abc:mainDetail"/>
                </xsd:sequence>
            </xsd:complexType>
        </xsd:element>
    
    </xsd:schema>



XML File:
=========

    code:


    <?xml version="1.0" encoding="UTF-8"?>
    <mainTag>
     <mainHeader>
             <TotalRecords><![CDATA[1]]></TotalRecords>
     </mainHeader>
     <mainDetail>
         <City><![CDATA[Chicago]]></City>
         <State><![CDATA[Illinois]]></State>
     </mainDetail>
    <mainTag>



ERROR MESSAGE:
==============
Error : cvc-elt.1: Cannot find the declaration of element 'mainTag'
IF I CHECK WITH FOLLOWING STARTING TAG IT WORKS PERFECTLY But following way we can't change from the thirdparty's XML:
=======================================
<mainTag xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://somesite.com/schemas/BaseDataTypes"
xsi:schemaLocation="http://somesite.com/schemas/BaseDataTypes http://somesite.com/schemas/mainInfo.xsd">

I USED THE FOLLOWING CODE FOR VALIDATING AGAINST THE XSD:
================================================== =======

    quote: import java.io.File;
    import java.util.ArrayList;
    import java.util.Iterator;
    import java.util.List;

    import javax.xml.parsers.DocumentBuilder;
    import javax.xml.parsers.DocumentBuilderFactory;

    import org.w3c.dom.Document;
    import org.xml.sax.SAXParseException;
    import org.xml.sax.helpers.DefaultHandler;


    public class DomValidator {
    static final String schemaSource = "c:\\testProject\\mainInfo.xsd";

    static final String xml_file = "c:\\testProject\\profile.xml";

    static final String JAXP_SCHEMA_LANGUAGE = "http://java.sun.com/xml/jaxp/properties/schemaLanguage";

    static final String JAXP_SCHEMA_SOURCE = "http://java.sun.com/xml/jaxp/properties/schemaSource";

    public static void main(String args[]) {


    try {
    DocumentBuilderFactory factory = DocumentBuilderFactory
    .newInstance();
    factory.setNamespaceAware(true);
    factory.setValidating(true);


    factory.setAttribute(JAXP_SCHEMA_LANGUAGE,
    "http://www.w3.org/2001/XMLSchema");
    factory.setAttribute(JAXP_SCHEMA_SOURCE, new File(schemaSource));


    DocumentBuilder domParser = factory.newDocumentBuilder();
    // Set Error Handler
    ErrorChecker errors = new ErrorChecker();
    domParser.setErrorHandler(errors);

    Document document = domParser.parse(new File(xml_file));
    List errorList = errors.getErrors();
    Iterator iter = errorList.iterator();
    while (iter.hasNext()) {
    String errroMessage = (String) iter.next();
    System.out.println(errroMessage);
    }
    } catch (Exception e) {
    e.printStackTrace();
    }

    }
    }

    // to capture the errors and warnings and the fatal errors occured

    class ErrorChecker extends DefaultHandler

    {
    public ArrayList errorList = new ArrayList();

    public ErrorChecker() {
    }

    public List getErrors() {
    return errorList;
    }

    public void error(SAXParseException e) {
    errorList.add("Error : " + e.getMessage() + " " + e.getPublicId() + " "
    + e.getSystemId());
    }

    public void warning(SAXParseException e) {
    errorList.add("Warning : " + e.getMessage());
    }

    public void fatalError(SAXParseException e) {
    errorList.add("Fatal error : " + e.getMessage());
    System.exit(1);
    }

    }



It would be great if anyone can suggest me without changing the existing XML structure to validate properly by changing in My Java program. Or guide me to the right direction would be appreiciated.

Well your schema says
  targetNamespace="http://somesite.com/BaseDataTypes"
if you don't want that then remove that attribute from the schema.

--
  Martin Honnen
  Microsoft MVP - XML

It complains if I remove this:
targetNamespace="http://somesite.com/schemas/BaseDataTypes"
    that the following should be same as the the target name:
schemaLocation="http://somesite.com/schemas/BaseDataTypes.xsd"

Well if BaseDataTypes.xsd also has the targetNamespace attribute set then you need to remove that as well if you want to include the schema. You can only include a schema targetting the same namespace. Otherwise you would need an import and not an include.

--
  Martin Honnen
  Microsoft MVP - XML

Is it possible to send me with the code snippet(for XSD AND BaseDataTypes) for this simple example to try with as I tried many ways but have no luck yet. The BaseDataTypes is refered here for :
<xsd:schema targetNamespace="http://somesite.com/schemas/BaseDataTypes">
<xsd:simpleType name="String30DataType">
<xsd:restriction base="xsd:string">
<xsd:maxLength value="30"/>
</xsd:restriction>
</xsd:simpleType>
</xsd:schema>

So please update my XSDs with your suggestion would be great , so that I can try here. Thanks

Untested.

--
  Martin Honnen
  Microsoft MVP - XML

I got the following error still :(

Error : src-include.2.1: The targetNamespace of the referenced schema, currently 'http://somesite.com/schemas/BaseDataTypes', must be identical to that of the including schema, currently 'null'. null http://somesite.com/schemas/BaseDataTypes.xsd