The <schema>
element is the root element of every XML Schema document:
<?xml version="1.0"?>
<xsd:schema>
...
...
</xsd:schema>
The <schema> element may
contain some attributes, which are described in XML Schema Part 1:
Structures of the standard. A typical schema declaration often looks
something like this:
<?xml version="1.0"?>
<xsd:schema
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
targetNamespace="http://www.eclipse.org/xsd/examples"
xmlns="http://www.eclipse.org/xsd/examples"
elementFormDefault="qualified">
...
...
</xs:schema>
- xmlns:xsd="http://www.w3.org/2001/XMLSchema" -
Indicates that the elements and data types used in the schema (schema, element,
complexType, sequence, string, int, etc.) come from the
"http://www.w3.org/2001/XMLSchema" namespace, which is also known as the schema
for schemas. It also specifies that the elements and data types that come from
the "http://www.w3.org/2001/XMLSchema" namespace should be prefixed with xsd in
the example above.
- xmlns="http://www.eclipse.org/xsd/examples" -
Indicates that the default namespace is "http://www.eclipse.org/xsd/examples".
- elementFormDefault="qualified" - Indicates that any elements
used by the XML instance document that were declared in this schema must be
namespace qualified.
The XML Schema model java interface for the
root <schema> is org.eclipse.xsd.XSDSchema and can be created by calling
org.eclipse.xsd.XSDFactory.eINSTANCE.createXSDSchema().