[KYUUBI #689] Fix MetricsSystemSuite on JDK 11

[pan3793]

Why are the changes needed?

Fix #689.

How was this patch tested?

• Add some test cases that check the changes thoroughly including negative and positive cases if possible

• Add screenshots for manual tests if appropriate

• Run test locally before make a pull request

[codecov-commenter]

Codecov Report

Merging #690 (7c4d258) into master (b3715c1) will not change coverage.
The diff coverage is n/a.

❗ Current head 7c4d258 differs from pull request most recent head bd64a66. Consider uploading reports for the commit bd64a66 to get more accurate results

@@           Coverage Diff           @@
##           master     #690   +/-   ##
=======================================
  Coverage   80.51%   80.51%           
=======================================
  Files         122      122           
  Lines        4738     4738           
  Branches      574      574           
=======================================
  Hits         3815     3815           
  Misses        601      601           
  Partials      322      322           

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[yaooqinn]

lgtm