feat(import): add support for multiple hbase snapshot imports

[tianlei2]

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b/429250716

This is the first PR that incorporates changes from https://github.com/jhambleton/java-bigtable-hbase/commits/dataflow-v2-v2.15.6 and some fixes to make it pass the tests.

• Fixed Test Isolation Issues
  SnapshotUtilsTest.testGetHbaseConfiguration was failing because the static configuration field SnapshotUtils.hbaseConfiguration cached state between test cases, leaking stale data into subsequent tests.
  • Solution: Added a @before setup method to reset the static field to null via reflection before every test run.
• Fixed Timestamp Formatting Tests
  SnapshotUtilsTest.testAppendCurrentTimestamp was throwing a NumberFormatException because the return value contained a UUID suffix (timestamp-UUID), but the test attempted to parse the entire string directly as a Long.
  • Solution: Updated the test to split the string using the "-" character to extract and correctly parse just the timestamp prefix.
• Resolved Classpath and SPI Conflicts (dnsjava)
  Integration tests failed on Java 8 and 11 in Kokoro because of unshaded transitive dependency conflicts (com.google.protobuf.LiteralByteString NoClassDefFoundError).
  • Solution: Reverted back to the shaded hbase-shaded-mapreduce dependency, ensuring proper compatibility across all Java versions.
• Uncommented and Fixed Tests in ImportJobFromHbaseSnapshotTest
  Several useful unit tests were commented out in ImportJobFromHbaseSnapshotTest because mockito-core lacked the ability to mock static methods.
  • Solution:
    Switched from mockito-core to mockito-inline in the pom.xml to allow static mocking.
    Uncommented the code and restored the original formatting to prevent any lint errors, enabling JUnit to verify correct configuration parsing.
• ComputeAndValidateHashFromBigtableDoFnTest.java was accidentally deleted, adding back
• Cleanups on unused comments

[tianlei2]

Integration test is run and passing:
https://fusion2.corp.google.com/invocations/33f68247-794b-45c2-8294-1b97ff42c5d0/artifacts/github%2Fjava-bigtable-hbase%2Fbigtable-dataflow-parent%2Fbigtable-beam-import%2Ftarget%2Ffailsafe-reports%2Fintegration-beam%2Fcom.google.cloud.bigtable.beam.hbasesnapshots.EndToEndIT;config=default

[mutianf]

/gemini review

[gemini-code-assist]

Code Review

This pull request introduces a new tool, HBaseSnapshotRestoreTool, and updates the existing ImportJobFromHbaseSnapshot to support loading multiple HBase snapshots into Bigtable. It includes several infrastructure improvements, such as adding necessary dependencies, introducing a RegionConfigCoder for efficient serialization, and enhancing the ReadRegions transform with dynamic splitting and sharding capabilities. My review identified several areas for improvement, including fixing an incorrect tracker claim in ReadSnapshotRegion, improving configuration handling in ImportJobFromHbaseSnapshot, ensuring consistent brace usage, and addressing potential null pointer exceptions and minor code style issues.

[mutianf]

I don't think the logic is correc,t I think checking the flag should be inside of convertAndValidateThresholds? And also, why pass in an empty list? I think we can just do List mutations = convertAndValidateThresholds(rowKey, element.getValue()..., snapshotName)

[mutianf]

There's also a EndToEnd IT failing, can you take a look?

com.google.cloud.bigtable.beam.hbasesnapshots.EndToEndIT.testHBaseSnapshotImportWithSharding -- Time elapsed: 434.2 s <<< FAILURE!
java.lang.AssertionError: expected: but was:
	at org.junit.Assert.fail(Assert.java:89)
	at org.junit.Assert.failNotEquals(Assert.java:835)
	at org.junit.Assert.assertEquals(Assert.java:120)
	at org.junit.Assert.assertEquals(Assert.java:146)
	at com.google.cloud.bigtable.beam.hbasesnapshots.EndToEndIT.testHBaseSnapshotImportWithSharding(EndToEndIT.java:508)

[tianlei2]

/gemini review

[tianlei2]

/gemini review

[mutianf]

Some final nits.

[mutianf]

/gemini review

[tianlei2]

/gemini review