[HADOOP-13641] Update UGI#spawnAutoRenewalThreadForUserCreds to reduce indentation

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 2.8.0, 3.0.0-alpha2
• Labels: newbie
• Target Version/s: 2.8.0
• Hadoop Flags: Reviewed
• Assignee: Huafeng Wang
• Reporter: Xiao Chen
• Created: 22/Sep/16 17:56
• Updated: 10/Oct/16 06:20
• Resolved: 10/Oct/16 05:48

Description

From drankye's comment in HADOOP-13590:

Could we return earlier at the beginning so we can avoid at least 2 level of indents and make the whole block more readable?

  /**Spawn a thread to do periodic renewals of kerberos credentials*/
  private void spawnAutoRenewalThreadForUserCreds() {
    if (isSecurityEnabled()) {
      //spawn thread only if we have kerb credentials
      if (user.getAuthenticationMethod() == AuthenticationMethod.KERBEROS &&
          !isKeytab) {
...
...
                             very deep nested ...
...