How can I have list of all users logged in (via spring security) my web application

Question

I\'m using spring security in my web application, and now I want to have a list of all users who are logged in my program.

How can I have access to that list? Aren\'

Answer 1

Similar to @rolyanos solution, mine for me always works:

- for the controller

@RequestMapping(value = "/admin")
public String admin(Map<String, Object> model) {

    if(sessionRegistry.getAllPrincipals().size() != 0) {
        logger.info("ACTIVE USER: " + sessionRegistry.getAllPrincipals().size());
        model.put("activeuser",  sessionRegistry.getAllPrincipals().size());
    }
    else
        logger.warn("EMPTY" );

    logger.debug(log_msg_a + " access ADMIN page. Access granted." + ANSI_RESET);
    return "admin";
}

- for the front end

<tr th:each="activeuser, iterStat: ${activeuser}">
    <th><b>Active users: </b></th> <td align="center" th:text="${activeuser}"></td>
    </tr>

- for spring confing

@Bean
public SessionRegistry sessionRegistry() {
    return new SessionRegistryImpl();
}

@Bean
public ServletListenerRegistrationBean<HttpSessionEventPublisher> httpSessionEventPublisher() {
    return new ServletListenerRegistrationBean<HttpSessionEventPublisher>(new HttpSessionEventPublisher());
}


@Override
protected void configure(HttpSecurity http) throws Exception {

    http.logout()
    .logoutSuccessUrl("/home")
    .logoutUrl("/logout")
    .invalidateHttpSession(true)
    .deleteCookies("JSESSIONID");


    http.authorizeRequests()
    .antMatchers("/", "/home")
    .permitAll()

    .antMatchers("/admin")
    .hasRole("ADMIN") 
    .anyRequest()
    .authenticated()

    .and()
    .formLogin()
    .loginPage("/home")
    .defaultSuccessUrl("/main")
    .permitAll()
    .and()
    .logout()
    .permitAll();

    http.sessionManagement().maximumSessions(1).sessionRegistry(sessionRegistry());

    http.authorizeRequests().antMatchers("/webjars/**").permitAll();

    http.exceptionHandling().accessDeniedPage("/403");
}