Check the formula string is null

[Pengpengwanga]

Signed-off-by: Pengpeng Wang pengpengw@vmware.com

[codecov]

Codecov Report

Merging #825 (0859388) into master (14c6f64) will increase coverage by 0.02%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##             master     #825      +/-   ##
============================================
+ Coverage     41.66%   41.69%   +0.02%     
- Complexity     1574     1577       +3     
============================================
  Files           233      233              
  Lines         12890    12891       +1     
  Branches       1727     1727              
============================================
+ Hits           5371     5375       +4     
+ Misses         6829     6826       -3     
  Partials        690      690              

Flag	Coverage Δ	Complexity Δ
aggregator	28.11% <ø> (ø)	63.00 <ø> (ø)
api	64.61% <0.00%> (+0.10%)	603.00 <0.00> (+3.00)
infoblox	54.04% <ø> (ø)	70.00 <ø> (ø)
labsdb	24.84% <ø> (ø)	30.00 <ø> (ø)
management	5.67% <ø> (ø)	9.00 <ø> (ø)
nlyte	30.88% <ø> (ø)	200.00 <ø> (ø)
openmanage	42.01% <ø> (ø)	152.00 <ø> (ø)
poweriq	42.21% <ø> (ø)	269.00 <ø> (ø)
vc	41.45% <ø> (ø)	165.00 <ø> (ø)
vro	5.46% <ø> (ø)	16.00 <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ	Complexity Δ
...java/com/vmware/flowgate/service/AssetService.java	80.21% <0.00%> (+0.13%)	259.00 <0.00> (+3.00)
...ware/flowgate/service/ServerValidationService.java	25.33% <0.00%> (+0.65%)	6.00 <0.00> (ø)