* issue-20804: Add nullability annotations to Java generated clients
Motivation:
Be able to use generated clients in code checked by tools like NullAway.
* issue-20804: Add nullability annotations to Java generated clients
Motivation:
Be able to use generated clients in code checked by tools like NullAway.
* issue-20804: Add nullability annotations to Java generated clients
Motivation:
Be able to use generated clients in code checked by tools like NullAway.
* Revert "v7.12.0 release"
This reverts commit 073723cb4d41187f839fbb46565d109293fa22d7.
* set version to v7.13.0-SNAPSHOT
* update samples
* update doc
* made Configuration.defaultApiClient volatile so that if it's changed the new value is immediately visible to all other threads
* made no-arg api ctor use Configuration.getDefaultApiClient() instead of creating new ApiClient every time
* replaced all use of URLEncoder.encode with ApiClient.urlEncode; just code cleanup; no functional changes
* disabled AbstractJavaCodegenTest.testGeneratedExampleValues as it fails, possibly due to timezone (Locale.ROOT) of local system
* replaced thread-unsafe SimpleDateFormat with DateTimeFormatter and re-enabled unit-test
* removed unused import
* ran the generate-sample scripts and generated a HUGE number of changes!
* added missing import of Configuration to api.mustache (and, thus, all native samples)
* added missing import for ApiClient to anyof and oneof model mustaches
