XML validation using XSD

I was using JAXB for reading one configuration file and before unmarshall, I want to validate the document. To do this we need to know two things:

1. How to link xml document with schema
2. How to configure SAX/DOM parser to use the schema and validate
   

Below are the excellent resources I found explaining above steps:

1. Link schema with xml
2. Configure parser to use schema for validation