/**
     * Loads the webapp properties based on servlet context information.
     * Returns a Properties object containing the settings, or null if unable
     * to load it. (The default file is WEB-INF/jspwiki.properties, and can
     * be overridden by setting PARAM_PROPERTYFILE in the server or webapp
     * configuration.)
     */
    private static Properties loadWebAppProps( ServletContext context )
    {
        String      additionalPropertyFile   = context.getInitParameter(PARAM_PROPERTYFILE);
        InputStream additionalPropertyStream = null;
        InputStream propertyStream = null;
        
        try
        {
            //  Use the default property file.
            propertyStream = context.getResourceAsStream(DEFAULT_PROPERTYFILE);

            if( propertyStream == null )
            {
                throw new WikiException("Default-Property file cannot be found!"+DEFAULT_PROPERTYFILE);
            }
            // Load Default Properties
            Properties props = new Properties( TextUtil.createProperties( DEFAULT_PROPERTIES ) );
            props.load( propertyStream );

            
            //
            //  Figure out where our properties lie.
            //
            if( additionalPropertyFile == null )
            {
                context.log("No "+PARAM_PROPERTYFILE+" defined for this context, using only default from "+DEFAULT_PROPERTYFILE);
            }
            else
            {
                context.log("Reading additional properties from "+additionalPropertyFile+" and merge to default.");
                Properties additionalProps = new Properties();
                additionalPropertyStream = new FileInputStream( new File(additionalPropertyFile) );
                if( additionalPropertyStream == null )
                {
                    throw new WikiException("Property file cannot be found!"+additionalPropertyFile);
                }
                additionalProps.load( additionalPropertyStream );
                props.putAll(additionalProps);
            }
            return( props );
        }
        catch( Exception e )
        {
            context.log( Release.APPNAME+": Unable to load and setup properties from jspwiki.properties. "+e.getMessage() );
        }
        finally
        {
            try
            {
                propertyStream.close();
                if (additionalPropertyStream != null)
                {
                    additionalPropertyStream.close();
                }
            }
            catch( IOException e )
            {
                context.log("Unable to close property stream - something must be seriously wrong.");
            }
        }

        return( null );
    }