import org.apache.hadoop.registry.client.exceptions.AuthenticationFailedException; //导入依赖的package包/类
/**
 * Given an exception and a possibly empty argument list, generate
 * a diagnostics string for use in error messages
 * @param operation the operation that failed
 * @param e exception
 * @param argsList arguments list
 * @return a string intended for the user
 */
String analyzeException(String operation,
    Exception e,
    List<String> argsList) {

  String pathArg = !argsList.isEmpty() ? argsList.get(1) : "(none)";
  if (LOG.isDebugEnabled()) {
    LOG.debug("Operation {} on path {} failed with exception {}",
        operation, pathArg, e, e);
  }
  if (e instanceof InvalidPathnameException) {
    return "InvalidPath :" + pathArg + ": " + e;
  }
  if (e instanceof PathNotFoundException) {
    return "Path not found: " + pathArg;
  }
  if (e instanceof NoRecordException) {
    return "No service record at path " + pathArg;
  }
  if (e instanceof AuthenticationFailedException) {
    return "Failed to authenticate to registry : " + e;
  }
  if (e instanceof NoPathPermissionsException) {
    return "No Permission to path: " + pathArg + ": " + e;
  }
  if (e instanceof AccessControlException) {
    return "No Permission to path: " + pathArg + ": " + e;
  }
  if (e instanceof InvalidRecordException) {
    return "Unable to read record at: " + pathArg + ": " + e;
  }
  if (e instanceof IOException) {
    return "IO Exception when accessing path :" + pathArg + ": " + e;
  }
  // something else went very wrong here
  return "Exception " + e;

}