public static boolean userHasAdministratorAccess(ServletContext servletContext,
    String remoteUser) {
    AccessControlList adminsAcl = (AccessControlList) servletContext.getAttribute(ADMINS_ACL);
    return userHasAdministratorAccess(adminsAcl, remoteUser);
  }
Get the admin ACLs from the given ServletContext and check if the given user is in the ACL.
@param servletContext the context containing the admin ACL.
@param remoteUser     the remote user to check for.
@return true if the user is present in the ACL, false if no ACL is set or the user is not
        present
hbase-http/src/main/java/org/apache/hadoop/hbase/http/HttpServer.java