java.fedora.server.validation.DOValidatorXMLSchema Maven / Gradle / Ivy

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/*
 * -----------------------------------------------------------------------------
 *
 * License and Copyright: The contents of this file are subject to the
 * Apache License, Version 2.0 (the "License"); you may not use 
 * this file except in compliance with the License. You may obtain a copy of 
 * the License at 
 * http://www.fedora-commons.org/licenses.
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
 * the specific language governing rights and limitations under the License.
 *
 * The entire file consists of original code.
 * Copyright © 2008 Fedora Commons, Inc.

 * 
Copyright © 2002-2007 The Rector and Visitors of the University of 
 * Virginia and Cornell University
 
 * All rights reserved.
 *
 * -----------------------------------------------------------------------------
 */
package fedora.server.validation;

// JAXP imports
import javax.xml.parsers.*;
import org.xml.sax.*;

import java.io.File;
import java.io.InputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URI;

import org.apache.log4j.Logger;

import fedora.server.errors.ObjectValidityException;
import fedora.server.errors.GeneralException;

/**
 * XML Schema validation for Digital Objects.
 *
 * @author [email protected]
 * @version $Id: DOValidatorXMLSchema.java 5218 2006-11-20 05:10:11Z cwilper $
 */
public class DOValidatorXMLSchema implements EntityResolver
{

    /** Logger for this class. */
    private static final Logger LOG = Logger.getLogger(
            DOValidatorXMLSchema.class.getName());

    /** Constants used for JAXP 1.2 */
    private static final String JAXP_SCHEMA_LANGUAGE =
        "http://java.sun.com/xml/jaxp/properties/schemaLanguage";
    private static final String W3C_XML_SCHEMA =
        "http://www.w3.org/2001/XMLSchema";
    private static final String JAXP_SCHEMA_SOURCE =
        "http://java.sun.com/xml/jaxp/properties/schemaSource";

    private URI schemaURI = null;

    public DOValidatorXMLSchema(String schemaPath) throws GeneralException
    {
      try
      {
        schemaURI = (new File(schemaPath)).toURI();
      }
      catch (Exception e)
      {
        LOG.error("Error constructing validator", e);
        throw new GeneralException(e.getMessage());
      }
    }

    public void validate(File objectAsFile)
      throws ObjectValidityException, GeneralException
    {
      try
      {
		validate(new InputSource(new FileInputStream(objectAsFile)));
      }
      catch (IOException e)
      {
        String msg = "DOValidatorXMLSchema returned error.\n"
                  + "The underlying exception was a " + e.getClass().getName() + ".\n"
                  + "The message was "  + "\"" + e.getMessage() + "\"";
        throw new GeneralException(msg);
      }
    }



    public void validate(InputStream objectAsStream)
      throws ObjectValidityException, GeneralException
    {
	  validate(new InputSource(objectAsStream));
    }

    private void validate(InputSource objectAsSource)
      throws ObjectValidityException, GeneralException
    {
      InputSource doXML = objectAsSource;
      try
      {
      // XMLSchema validation via SAX parser
      SAXParserFactory spf = SAXParserFactory.newInstance();
      spf.setNamespaceAware(true);
      spf.setValidating(true);
      SAXParser sp = spf.newSAXParser();
      sp.setProperty(JAXP_SCHEMA_LANGUAGE, W3C_XML_SCHEMA);

      // JAXP property for schema location
      sp.setProperty(
        "http://java.sun.com/xml/jaxp/properties/schemaSource",
        schemaURI.toString());

      XMLReader xmlreader = sp.getXMLReader();
      xmlreader.setErrorHandler(new DOValidatorXMLErrorHandler());
      xmlreader.setEntityResolver(this);
      xmlreader.parse(doXML);
      }
      catch (ParserConfigurationException e)
      {
        String msg = "DOValidatorXMLSchema returned parser error.\n"
                  + "The underlying exception was a " + e.getClass().getName() + ".\n"
                  + "The message was "  + "\"" + e.getMessage() + "\"";
        throw new GeneralException(msg, e);
      }
      catch (SAXException e)
      {
        String msg = "DOValidatorXMLSchema returned validation exception.\n"
                  + "The underlying exception was a " + e.getClass().getName() + ".\n"
                  + "The message was "  + "\"" + e.getMessage() + "\"";
        throw new ObjectValidityException(msg, e);
      }
      catch (Exception e)
      {
        String msg = "DOValidatorXMLSchema returned error.\n"
                  + "The underlying error was a " + e.getClass().getName() + ".\n"
                  + "The message was "  + "\"" + e.getMessage() + "\"";
        throw new GeneralException(msg, e);
      }
    }

    /**
     * Resolve the entity if it's referring to a local schema.
     * Otherwise, return an empty InputSource.
     *
     * This behavior is required in order to ensure that Xerces never
     * attempts to load external schemas specified with xsi:schemaLocation.
     * It is not enough that we specify processContents="skip" in our own
     * schema.
     */
    public InputSource resolveEntity(String publicId, String systemId) {
        if (systemId != null && systemId.startsWith("file:")) {
            return null;
        } else {
            return new InputSource();
        }
    }
}