How do I validate an XML file against XSD file?

import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;

import javax.xml.XMLConstants;
import javax.xml.transform.Source;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;

import org.xml.sax.SAXException;

public class XMLValidation {

	public static void main(String[] args) throws MalformedURLException {
		URL schemaFile = new URL("http://host:port/filename.xsd");
		Source xmlFile = new StreamSource(new File("web.xml"));
		SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
		try {
			Schema schema = schemaFactory.newSchema(schemaFile);
			Validator validator = schema.newValidator();
			validator.validate(xmlFile);
			System.out.println(xmlFile.getSystemId() + " is valid.");
		} catch (SAXException e) {
			System.out.println(xmlFile.getSystemId() + " is NOT valid xml, The reason is:" + e);
		} catch (IOException e) {
		}
	}

}