Schema Validation Example

import java.io.*;
import javax.xml.transform.Source;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.*;
import org.xml.sax.SAXException;

public class DocbookXSDCheck {

  public static void main(String[] args) throws SAXException, IOException {

    // 1. Lookup a factory for the W3C XML Schema language
    SchemaFactory factory = 
      SchemaFactory.newInstance("http://www.w3.org/2001/XMLSchema");
    
    // 2. Compile the schema. 
    // Here the schema is loaded from a java.io.File, but you could use 
    // a java.net.URL or a javax.xml.transform.Source instead.
    File schemaLocation = new File("/opt/xml/docbook/xsd/docbook.xsd");
    Schema schema = factory.newSchema(schemaLocation);
  
    // 3. Get a validator from the schema.
    Validator validator = schema.newValidator();
    
    // 4. Parse the document you want to check.
    Source source = new StreamSource(args[0]);
    
    // 5. Check the document
    try {
      validator.validate(source);
      System.out.println(args[0] + " is valid.");
    }
    catch (SAXException ex) {
      System.out.println(args[0] + " is not valid because ");
      System.out.println(ex.getMessage());
    }  
    
  }

}