Here is a description of the files that reside in the $JONAS_ROOT/examples/src/sb directory:
ClientOp.java is the Java client that accesses the JOnAS server.
jonas-sb.xml is the JOnAS specific part of the deployment descriptor.
OpBean.java contains the bean implementation code.
OpHome.java contains the home interface of the bean.
Op.java contains the remote interface of the bean.
sb.xml is the standard part of the deployment descriptor.