Specifying Schema Location in XML file and not in the Java code

Question

I have a repository of schema xsd files. When I receive my xml file, I need to validate it against the specified schema. The xml file would declare the schema location, using the following syntax:
<CERD:CERD xsi:schemaLocation = "..\CERD.xsd" xmlns:CERD = "CERD.xsd" xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance">
Is it really necessary to define the schema location again in the JAVA code? Why set the schemaLocation in the xml file at all then?
Does anybody have any examples where the schema location is not set in the JAVA code? I am using Java 1.6, and at this point in time I only need to validate. Any help would be appreciated.

Answer 1

Thank you very much for your quick reply. I have made some progress but I am still stumped.
In my code I am doing this:
SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
Schema schema = factory.newSchema();
Validator validator = schema.newValidator();
validator.validate(XML_SOURCE);
I find this works if my schema does not have a target namespace. I have downloaded the following simple example from the internet that uses a target namespace and it fails:
library1.xsd:
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://example.org/prod"
xmlns:prod="http://example.org/prod">
<xsd:element name="product" type="prod:ProductType"/>
<xsd:complexType name="ProductType">
<xsd:sequence>
<xsd:element name="number" type="xsd:integer"/>
<xsd:element name="size" type="prod:SizeType"/>
</xsd:sequence>
<xsd:attribute name="effDate" type="xsd:date"/>
</xsd:complexType>
<xsd:simpleType name="SizeType">
<xsd:restriction base="xsd:integer">
<xsd:minInclusive value="2"/>
<xsd:maxInclusive value="18"/>
</xsd:restriction>
</xsd:simpleType>
</xsd:schema>
<prod:product xmlns:prod="http://example.org/prod"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="library1.xsd"
effDate="2001-04-02">
<number>557</number>
<size>10</size>
</prod:product>
I get the following SAXParseException when I validate:
[line 4, col 36|
cvc-elt.1: Cannot find the declaration of element 'prod:product'.
Am I doing something wrong with the namespace declaration?
Edited by: alfredamorrissey on Oct 31, 2007 6:34 AM