[#3354 ]add a test case for not null

[liubao68]

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[codecov-commenter]

Codecov Report

Merging #3439 (a5d3b46) into master (d03cff6) will increase coverage by 0.00%.
The diff coverage is 80.00%.

@@            Coverage Diff            @@
##             master    #3439   +/-   ##
=========================================
  Coverage     77.58%   77.58%           
  Complexity     1466     1466           
=========================================
  Files          1650     1650           
  Lines         43948    43953    +5     
  Branches       3700     3700           
=========================================
+ Hits          34095    34100    +5     
  Misses         8309     8309           
  Partials       1544     1544           

Impacted Files	Coverage Δ
...xrs/client/validation/ValidationServiceClient.java	74.60% <80.00%> (+2.18%)	⬆️

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