user manual

Chapter 11: Writing enterprise bean clients 113
EJB to CORBA mapping
Current current = Current.narrow( obj );
if( current == NULL ) {
cerr << "Couldn't resolve current" << endl;
exit( 1 );
}
// execute transaction
try {
current->begin();
atmSession->transfer("checking", "saving", 100.00 );
current->commit( 0 );
} catch( ... ) {
current->rollback();
}
}
catch( ... ) {
...
}
Mapping for security
Security aspects of the EJB specification focuses on controlling access to
enterprise beans. CORBA defines a number of ways to define the identities,
including the following cases:
■
Plain IIOP. CORBA's principal interface was deprecated in early 1998. The
principal interface was intended for determining the identity of a client.
However, the authors of the CORBA security services implemented a
different approach, GIOP.
■
The GIOP specification contains a component called service context, which
is an array of value pairs. The identifier is a CORBA long and the value is a
sequence of octet. Among other purposes, entries in the service context
can be used to identify a caller.
■
Secure IIOP. The CORBA security specification defines an opaque data
type for the identity. The real type of the identity is determined by the
chosen security mechanism; for example, GSS Kerberos, SPKM, or CSI-
ECMA.
■
IIOP over SSL. SSL uses X.509 certificates to identify servers and,
optionally, clients. When a server requests a client certificate, the server
can use the certificate as a client identity.