* Deduplicate DataSegments contents (loadSpec's keys, dimensions and metrics lists as a whole) more aggressively; use ArrayMap instead of default LinkedHashMap for DataSegment.loadSpec, because they have only 3 entries on average; prune DataSegment.loadSpec on brokers
* Fix DataSegmentTest
* Refinements
* Try to fix
* Fix the second DataSegmentTest
* Nullability
* Fix tests
* Fix tests, unify to use TestHelper.getJsonMapper()
* Revert TestUtil as ServerTestHelper, fix tests
* Add newline
* Fix indexing tests
* Fix s3 tests
* Try to fix tests, remove lazy caching of ObjectMapper in TestHelper, rename TestHelper.getJsonMapper() to makeJsonMapper()
* Fix HDFS tests
* Fix HdfsDataSegmentPusherTest
* Capitalize constant names
* Avoid usages of Default system Locale and printing to System.out or System.err in production code
* Fix Charset in DruidKerberosUtil
* Remove redundant string format in GenericIndexed
* Rename StringUtils.safeFormat() to unimportantSafeFormat(); add StringUtils.format() which fails as well as String.format()
* Fix testSafeFormat()
* More fixes of redundant StringUtils.format() inside ISE
* Rename unimportantSafeFormat() to nonStrictFormat()
* Make using implicit system charset an error
* Use StringUtils.toUtf8() and fromUtf8() instead of String.getBytes() and new String()
* Use English locale in StringUtils.safeFormat()
* Restore comment
* Adding s3a schema and s3a implem to hdfs storage module.
* use 2.7.3
* use segment pusher to make loadspec
* move getStorageDir and makeLoad spec under DataSegmentPusher
* fix uts
* fix comment part1
* move to hadoop 2.8
* inject deep storage properties
* set version to 2.7.3
* fix build issue about static class
* fix comments
* fix default hadoop default coordinate
* fix create filesytem
* downgrade aws sdk
* bump the version
* Make Errorprone the default compiler
* Address comments
* Make Error Prone's ClassCanBeStatic rule a error
* Preconditions allow only %s pattern
* Fix DruidCoordinatorBalancerTester
* Try to give the compiler more memory
* Remove distribution module activation on jdk 1.8 because only jdk 1.8 is used now
* Don't show compiler warnings
* Try different travis script
* Fix travis.yml
* Make Error Prone optional again
* For error-prone compiler
* Increase compiler's maxmem
* Don't run Error Prone for benchmarks because of OOM
* Skip install step in Travis
* Remove MetricHolder.writeToChannel()
* In travis.yml, check compilation before tests, because it may fail faster
* In IndexMerger and IndexMergerV9, create temporary files under the output directory/tmpPeonFiles, instead of java.io.tmpdir
* Use FileUtils.forceMkdir() across the codebase and remove some unused code
* Fix test
* Fix PullDependencies.run()
* Unused import
* support finding segments from a AWS S3 storage.
* add more Uts
* address comments and add a document for the feature.
* update docs indentation
* update docs indentation
* address comments.
1. add a Ut for json ser/deser for the config object.
2. more informant error message in a Ut.
* address comments.
1. use @Min to validate the configuration object
2. change updateDescriptor to a string as it does not take an argument otherwise
* fix a Ut failure - delete a Ut for testing default max length.
* Allow S3 version finder to search entire s3 object key
* Previously only was able to search immediate "directory"
* Update method javadoc
* Expand docs a bit better
* Make S3DataSegmentPuller do GET requests less often
* Fixes#2894
* Run intellij formatting on S3Utils
* Remove forced stream fetching on getVersion
* Remove unneeded finalize
* Allow initial object fetching to fail and be retried