fix issue that cant decode java generic type

[wongoo]

What this PR does:

fix issue #238 that cant decode java generic type

Which issue(s) this PR fixes:

Fixes #238

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

- fix issue that cant decode java generic type

[codecov-io]

Codecov Report

Merging #239 into master will increase coverage by 0.00%.
The diff coverage is 71.42%.

@@           Coverage Diff           @@
##           master     #239   +/-   ##
=======================================
  Coverage   66.18%   66.18%           
=======================================
  Files          25       25           
  Lines        2762     2768    +6     
=======================================
+ Hits         1828     1832    +4     
- Misses        707      708    +1     
- Partials      227      228    +1     

Impacted Files	Coverage Δ
object.go	65.60% <71.42%> (+0.02%)	⬆️

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