OIM API - Code Snippet to Set Display Name of User.

public void setDisplayNameOfUser(String userKey, String displayName){
        final String logp = CN + " :: setDisplayNameOfUser - ";
        LOGGER.log(Level.FINEST, logp + "START");
        HashMap<String, Object> modifyMap = new HashMap<String, Object>();
       
        //get user manager service
        UserManager usrService = Platform.getService(UserManager.class);
       
        //create display name map
        HashMap displayNameMap = new HashMap();
        displayNameMap.put("base", displayName);
        modifyMap.put(UserManagerConstants.AttributeName.DISPLAYNAME.getId(), displayNameMap);
       
        try{
            User newUser = new User(userKey, modifyMap);
            LOGGER.log(Level.INFO, logp + "User to update :: " + userKey);
            UserManagerResult result = usrService.modify(AttributeName.USER_KEY.getId(), userKey, newUser);
            LOGGER.log(Level.INFO, logp + "Operations Status :: " + result.getStatus());
        }catch(Exception e){
            LOGGER.log(Level.SEVERE, logp + "Exception occured :: " ,e.getMessage());
        }
        Logger.log(Level.FINEST, logp + "END");
 } 

Happy Learning!!!!