Java Driver 5.6.0 (September 11, 2025)

What's Changed 🚀

Credential Handling

• Fix OIDC reauthentication when a session is involved #1719
• Add X509 authentication tests #1771
• Fix OIDC tests #1753
• Add CSOT to OIDC #1741

Performance Optimizations

• Clear CommandCursorResult.results after next()/tryNext() #1780
• Ignore maxWaitTime when CSOT is enabled #1744
• Simplify Operations by uniting Sync and Async operations #1776

Resource Management

• Fix Netty reference leak #1762
• Properly handle exceptions in threads created by MongoClient #1764
• Propagate timeout errors to callback #1761
• Merge changes from tls-channel to prevent accidentally calling SSLEngine #1726

Compatibility and Maintenance

• Handle dropIndex behavior change #1785
• Remove Legacy based ClientSideEncryptionTests #1799
• Remove code that won't execute on supported server releases #1704
• Simplify tests based on 4.2 minimum server support #1712
• Update libmongocrypt version to 1.14.1 #1778
• Deprecate MongoNamespace#COMMAND_COLLECTION_NAME #1786
• Remove internal use of MongoNamespace.COMMAND_COLLECTION_NAME #1782

Benchmarks and Testing

• Support text indexes with encryption #1797
• Ensure encrypted fields data exists fully #1802
• CSFLE auto encryption tests improvements #1788
• Normalize async and sync ClientSideOperationTimeoutProseTest #1800
• Add prose test to verify server monitors do not gossip cluster time #1766
• Added logging specification tests #1740
• Include submodules to OIDC testing #1703

Bug Fixes and Stability

• Fix duplicate field name serialization with @BsonDiscriminator and getter #1610
• Fix Scala UnifiedTest import (No PR link)
• Temporarily limit TypeMqlValuesFunctionalTest.asString server version #1803
• Fix parameterized test names in CrudProseTest #1775
• Improve MongoTimeoutException thrown by DefaultConnectionPool #1767
• Improve error message clarity in MongoCommandException #1789
• Ensure socks5 proxy option parsing is to specification #1688

Documentation and Quality of Life

• Update README.md #1716
• Add JavaDoc to NamespaceType #1754
• Include error messages for stale primary #1714
• Added operation (aka command name) to structured logging #1758

Kotlin Improvements

• JAVA-3815: Pojo Codec - Detect property models on extended interfaces #563
• Ensure custom KProperty include the name in the hashcode #1710

Test Enhancements

• Add support for awaiting CommandStartedEvent in Unified Test Runner #1790
• Update specifications and skip optional rawData based tests #1772
• Improve test clarity and execution time #1743
• Fix datalake and k8s test failures #1720
• Improve Netty test variants #1721

Infrastructure Improvements

• Automate closing and releasing maven artifacts when publishing #1757
• Auto close the repository on publish #1755
• Update waiting times for the transition stage #1756
• Update the evergreen build to use the AWS secrets manager (No PR link)
• Evergreen added shell script to create a git archive #1718
• Add CODEOWNERS file #1739
• Github action fix echo'd file name #1804

All Other Changes

• Add Client Metadata Update Support #1708
• Add namespace type support to ChangeStreamDocument #1736
• Simplify RequestMessage class hierarchy #1787
• Remove unused OperationTypeCodec #1746
• Use OperationContext with NOOP Session #1733
• Publish ClusterDescriptionChangedEvent on topology close #1738
• Ensure serverHeartbeatEvent is sent before opening a connection #1715
• Update the DEFAULT_CODEC_REGISTRY order #1795
• Add parameter type in reflect-config.json for ChangeStreamDocument #1759
• Added ClientEncryption methods to scala #1779
• Modify a redundant code for CAPIHelper #1653
• sunset Astrolabe #1769
• Multiple build dependency updates #1801, #1794, #1783, #1773, #1763, #1748, #1735, #1724, #1713, #1711, #1698
• Various version bumps and snapshot updates (Multiple commits without PR links)
• Various CI/CD and infrastructure adjustments (Multiple commits without PR links)

New Contributors

New Contributors

• @abalanonline made their first contribution in #1764
• @zzypersonally made their first contribution in #1653
• @raffaeleflorio made their first contribution in #1610
• @rishitb-mongodb made their first contribution in #1716

Full Changelog: r5.5.1...r5.6.0

Verifying artifact signatures

Please refer to https://www.mongodb.com/docs/drivers/java/sync/v5.4/security/validate-signatures/ for the full procedure.

To download and import the public key for verifying signatures, execute

gpg --keyserver hkps://keyserver.ubuntu.com --recv-keys 1a75005e142192223d6a7c3b76e0008d166740a8