code: @Override
      public Object set(String key, Object value) throws CredentialDestroyedException, CredentialExpiredException {
          SecurityManager sm = System.getSecurityManager();
          if (key.startsWith("wssecurity")) {
              if (sm != null) {
                  sm.checkPermission(UPDATE_PERMISSION);
              }
          }
          if (hashTable.get(key) != null) {
              if (sm != null) {
                  sm.checkPermission(APP_UPDATE_PERMISSION);
              }
          }
          return hashTable.put(key, value);
      }
docs: {@inheritDoc}