This looks like a standalone t3 client application (not running in a container). Thus, you'll need weblogic's full client (wlfullclient.jar) to be in your client application's classpath (read more: http://docs.oracle.com/cd/E11035_01/wls100/client/basics.html#wp1066820).
However, you'll have to generate this particular jar file using a tool called JarBuilder. And this is how: http://docs.oracle.com/cd/E11035_01/wls100/client/jarbuilder.html