doConfigure method in Configuration class

[Sim Kim]

Hi All,

I am using Hibernate for about a month now . I happened to browse the source code of Configuration class of hibernate3.jar .

If you see there is a method called doConfigure .

 
protected Configuration doConfigure(InputStream stream, String resourceName) throws HibernateException { 
 
      org.dom4j.Document doc; 
      try { 
         List errors = new ArrayList(); 
         doc = xmlHelper.createSAXReader( resourceName, errors, entityResolver ) 
               .read( new InputSource( stream ) ); 
         if ( errors.size() != 0 ) { 
            throw new MappingException( 
                  "invalid configuration", 
                  (Throwable) errors.get( 0 ) 
               ); 
         } 
      } 
      catch (DocumentException e) { 
         throw new HibernateException( 
               "Could not parse configuration: " + resourceName, 
               e 
            ); 
      } 
      finally { 
         try { 
            stream.close(); 
         } 
         catch (IOException ioe) { 
            log.warn( "could not close input stream for: " + resourceName, ioe ); 
         } 
      } 
 
      return doConfigure( doc ); 
 
   } 
 
Here the "doc" variable has not been initialiazed anywhere (before the try bolck). This should have been a compilation issue . 
 
Any inputs ?
 
   

[Paul Sturrock]

So you are suggesting the compiler got it wrong?!

Try this code:

public class Test {

    public static void main(String []args)  {
        Document doc;
        try {
            doc = returnADocument();
        } catch (Exception e) {
            
        }
    }
    
    
    public static Document returnADocument() {
        return null;
    }
    
}

Does it compile?

[Sim Kim]

public class Test {
public static void main(String []args)  {
Integer doc;
try {
doc = null;
returnADocument(doc);  // Line 1
} catch (Exception e) {
}
returnADocument(doc); // Line 2
}
 
public static Integer returnADocument(Integer doc) {
return null;
}
}

Here Line 1 will not give error but Line 2 will certainly give !!! This is what doConfigure() method is doing