container-common/src/main/java/com/streamsets/datacollector/security/SecurityContext.java
public synchronized void logout() {
    if (subject != null) {
      LOG.debug("Logout. Kerberos enabled '{}', Principal '{}'", securityConfiguration.isKerberosEnabled(),
        subject.getPrincipals());
      if (loginContext != null) {
        try {
          loginContext.logout();
        } catch (LoginException ex) {
          LOG.warn("Error while doing logout from Kerberos: {}", ex.toString(), ex);
        } finally {
          loginContext = null;
        }
      }
      subject = null;
    }
  }
public synchronized void logout() {
    if (subject != null) {
      LOG.debug("Logout. Kerberos enabled '{}', Principal '{}'", securityConfiguration.isKerberosEnabled(),
        subject.getPrincipals());
      if (loginContext != null) {
        try {
          loginContext.logout();
        } catch (LoginException ex) {
          LOG.warn("Error while doing logout from Kerberos: {}", ex.toString(), ex);
        } finally {
          loginContext = null;
        }
      }
      subject = null;
    }
  }
Logs out. If Keberos is enabled it logs out from the KDC, otherwise is a NOP.