Use standard object writer for errors

[clementdenis]

No description provided.

[codecov-io]

Codecov Report

Merging #24 into master will increase coverage by 0.02%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master      #24      +/-   ##
============================================
+ Coverage     80.95%   80.97%   +0.02%     
- Complexity     1721     1723       +2     
============================================
  Files           159      159              
  Lines          6395     6397       +2     
  Branches        830      831       +1     
============================================
+ Hits           5177     5180       +3     
  Misses          907      907              
+ Partials        311      310       -1

Impacted Files	Coverage Δ	Complexity Δ
.../server/spi/response/RestResponseResultWriter.java	100% <100%> (ø)	6 <0> (ø)	⬇️
...rver/spi/response/ServletResponseResultWriter.java	95.29% <100%> (+0.11%)	19 <0> (+1)	⬆️
.../server/spi/discovery/CommonPathPrefixBuilder.java	100% <0%> (+5.55%)	9% <0%> (+1%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 0cc6b91...09f5089. Read the comment docs.

[RaHery]

Reviewed 2 of 2 files at r1.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @alarribeau, @clementdenis, and @llbrt)

---

endpoints-framework/src/main/java/com/google/api/server/spi/response/ServletResponseResultWriter.java, line 96 at r1 (raw file):

    }
    this.objectWriter = configureWriter(objectWriter);
    this.errorObjectWriter = objectWriter;

The method configureObject(..) is not a pure function: it may change the state of the input parameter objectWriter. If it does, the errorObjectWriter would inherit the side effect of this change.
It would be safer to assign a different object to errorObjectWriter instead of reusing the same instance.

[clementdenis]

From the ObjectWriter Javadoc:

new instances are constructed for different configurations

So com.fasterxml.jackson.databind.ObjectWriter instances are effectively immutable, their state can't be changed, so the logic here should be OK.

[RaHery]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @alarribeau, @clementdenis, and @llbrt)

[llbrt]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @alarribeau, @clementdenis, and @llbrt)

[llbrt]

Reviewed 2 of 2 files at r1.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @alarribeau and @clementdenis)

[RaHery]

Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @alarribeau)