URL url = jar.toURL();
URI uri = jar.toURI(); URL url = uri.toURL();
    public SystemClassLoader( ClassLoader parent )    {        super( "system", Category.SYSTEM, new URL[0], parent );                m_parent = parent;                if( "true".equals( System.getProperty( "dpml.transit.include.tools" ) ) )        {            String jrePath = System.getProperty( "java.home" );            try            {                File jre = new File( jrePath );                File jdk = jre.getParentFile();                File lib = new File( jdk, "lib" );                File jar = new File( lib, "tools.jar" );                URL url = jar.toURL();                addURL( url );            }            catch( Throwable e )            {                final String error =                   "Internal error while attempting to establish tools.jar in the system classloader.";                throw new PartError( error, e );            }        }    }