XML validation using xml schema string

[Praveen Peddi <pp...@contextmedia.com>]

Hi all,
I want to validate an xml document with an existing schema. I know there is a code to do it when the schema is present as a URL. BUt in my case schema is present with in the application memory (since it is stored in the database) and that is not the url or on the hard disk.
I have the following method which validates only when the schema is present externally. Note that the argument Schema is a URL:
public static void DOMValidate(String XMLfile, String Schema){
  long startTime = System.currentTimeMillis();        

        // Instantiate the DOM parser.
        DOMParser parser = new DOMParser();

        // set the features
        try{
            parser.setFeature("http://xml.org/sax/features/namespaces",true);
            parser.setFeature("http://xml.org/sax/features/validation", true);
            parser.setFeature("http://apache.org/xml/features/validation/schema",true);
            parser.setFeature("http://apache.org/xml/features/validation/schema-full-checking",true);
            // convert the xml file name to a URL
            String SystemId = null;
            try{
                SystemId = new File(Schema).toURL().toExternalForm();
            } catch(java.net.MalformedURLException ex){
                //ex.printStackTrace();
                log.error(ex);
            }
            parser.setProperty("http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation",SystemId);
            // myErrorHandler is a descendant of ErrorHandler, it should be set here to be able to catch parse errors
            parser.setErrorHandler(new SchemaErrorHandler());

        } catch (SAXNotSupportedException ex){
            System.out.println("SAXNotSupportedException Exception");
        } catch (SAXNotRecognizedException ex){
                System.out.println("SAXNotRecognizedException Exception");
        }

        // parse the xml file, the errorhandler class has callbacks,
        // so those will be called automatically there is a parse error
        try{
                parser.parse(new File(XMLfile).toURL().toExternalForm());
                //System.out.println("Parsed Successfully by DOM Parser");
        } catch (org.xml.sax.SAXException ex){
                //System.out.println("SAXException Exception");
                //ex.printStackTrace();
            log.error(ex);
        } catch (java.io.IOException ex){
                System.out.println("IOException Exception");
   } finally {
   long endTime = System.currentTimeMillis();
         //System.out.println("Total time of DOMValidate:"+(endTime-startTime));
 
 }

    }

How can I do the validation if the Schema is the actual schema string not the url. This looks like a common problem. I assume that its not universal that schema is not always stored externally.

Any suggestions are appreciated.

Praveen

Re: XML validation using xml schema string

[Praveen Peddi <pp...@contextmedia.com>]

Hi all,
Last week I sent an email regarding the xml validation against the schema, but didn't get any reply. Please reply if any one has answer to my question. Is it possible to validate an xml document using a schema document (not the schema url) that is present with in the application. If its not possible, whats the best way of achieving it. Please read my previous email below.

Thanks
Praveen


  Hi all,
  I want to validate an xml document with an existing schema. I know there is a code to do it when the schema is present as a URL. BUt in my case schema is present with in the application memory (since it is stored in the database) and that is not the url or on the hard disk.
  I have the following method which validates only when the schema is present externally. Note that the argument Schema is a URL:
  public static void DOMValidate(String XMLfile, String Schema){
    long startTime = System.currentTimeMillis();        

          // Instantiate the DOM parser.
          DOMParser parser = new DOMParser();

          // set the features
          try{
              parser.setFeature("http://xml.org/sax/features/namespaces",true);
              parser.setFeature("http://xml.org/sax/features/validation", true);
              parser.setFeature("http://apache.org/xml/features/validation/schema",true);
              parser.setFeature("http://apache.org/xml/features/validation/schema-full-checking",true);
              // convert the xml file name to a URL
              String SystemId = null;
              try{
                  SystemId = new File(Schema).toURL().toExternalForm();
              } catch(java.net.MalformedURLException ex){
                  //ex.printStackTrace();
                  log.error(ex);
              }
              parser.setProperty("http://apache.org/xml/properties/schema/external-noNamespaceSchemaLocation",SystemId);
              // myErrorHandler is a descendant of ErrorHandler, it should be set here to be able to catch parse errors
              parser.setErrorHandler(new SchemaErrorHandler());

          } catch (SAXNotSupportedException ex){
              System.out.println("SAXNotSupportedException Exception");
          } catch (SAXNotRecognizedException ex){
                  System.out.println("SAXNotRecognizedException Exception");
          }

          // parse the xml file, the errorhandler class has callbacks,
          // so those will be called automatically there is a parse error
          try{
                  parser.parse(new File(XMLfile).toURL().toExternalForm());
                  //System.out.println("Parsed Successfully by DOM Parser");
          } catch (org.xml.sax.SAXException ex){
                  //System.out.println("SAXException Exception");
                  //ex.printStackTrace();
              log.error(ex);
          } catch (java.io.IOException ex){
                  System.out.println("IOException Exception");
     } finally {
     long endTime = System.currentTimeMillis();
           //System.out.println("Total time of DOMValidate:"+(endTime-startTime));
   
   }

      }

  How can I do the validation if the Schema is the actual schema string not the url. This looks like a common problem. I assume that its not universal that schema is not always stored externally.

  Any suggestions are appreciated.

  Praveen