Below is the code which does the authenticate and then call the secured resource api. Also i have used default CallbackHandler, you can use user callback if you to

javax.security.auth.login.LoginContext lc = null;

try {
lc = new javax.security.auth.login.LoginContext(“WSLogin”,
new com.ibm.websphere.security.auth.callback.WSCallbackHandlerImpl
(“usernam”, “password”));

// create a LoginContext and specify a CallbackHandler implementation
// CallbackHandler implementation determine how authentication data is collected
// in this case, the authentication data is “pushed” to the authentication
// mechanism implemented by the LoginModule.
} catch(javax.security.auth.login.LoginException e) {
System.err.println(“ERROR: failed to instantiate a LoginContext ”
+ “and the exception: ” + e.getMessage());
e.printStackTrace();

// may be javax.security.auth.AuthPermission “createLoginContext” is not granted
// to the application, or the JAAS login configuration is not defined.
}

if (lc != null)
{
try
{

lc.login(); // perform login

// get the authenticated subject
javax.security.auth.Subject s = lc.getSubject();

// Invoke a J2EE resources using the authenticated subject
com.ibm.websphere.security.auth.WSSubject.doAs(s,
new java.security.PrivilegedAction()
{
public Object run() {
try {
bankAccount.deposit(100.00);
// where bankAccount is an protected resource
} catch (Exception e) {
System.out.println(“ERROR: error while accessing resource, exception: ” +
e.getMessage());
e.printStackTrace();
}
return null;
}
});

} catch (javax.security.auth.login.LoginException e)
{
System.err.println(“ERROR: login failed with exception: ” + e.getMessage());
e.printStackTrace();

// login failed, might want to provide relogin logic
}
}

}

Thank you!