v2.10

• Support for serializing and deserializing Java records, on Java ≥ 16. (#​2201)
• Add JsonArray.asList and JsonObject.asMap view methods (#​2225)
• Fix TypeAdapterRuntimeTypeWrapper not detecting reflective TreeTypeAdapter and FutureTypeAdapter (#​1787)
• Improve JsonReader.skipValue() (#​2062)
• Perform numeric conversion for primitive numeric type adapters (#​2158)
• Add Gson.fromJson(..., TypeToken) overloads (#​1700)
• Fix changes to GsonBuilder affecting existing Gson instances (#​1815)
• Make JsonElement conversion methods more consistent and fix javadoc (#​2178)
• Throw UnsupportedOperationException when JsonWriter.jsonValue is not supported (#​1651)
• Disallow JsonObject Entry.setValue(null) (#​2167)
• Fix TypeAdapter.toJson throwing AssertionError for custom IOException (#​2172)
• Convert null to JsonNull for JsonArray.set (#​2170)
• Fixed nullSafe usage. (#​1555)
• Validate TypeToken.getParameterized arguments (#​2166)
• Fix #​1702: Gson.toJson creates CharSequence which does not implement toString (#​1703)
• Prefer existing adapter for concurrent Gson.getAdapter calls (#​2153)
• Improve ArrayTypeAdapter for Object[] (#​1716)
• Improve AppendableWriter performance (#​1706)

v2.9.1

• Make Object and JsonElement deserialization iterative rather than
  recursive (#​1912)
• Added parsing support for enum that has overridden toString() method (#​1950)
• Removed support for building Gson with Gradle (#​2081)
• Removed obsolete codegen hierarchy (#​2099)
• Add support for reflection access filter (#​1905)
• Improve TypeToken creation validation (#​2072)
• Add explicit support for float in JsonWriter (#​2130, #​2132)
• Fail when parsing invalid local date (#​2134)

Also many small improvements to javadoc.

v2.9.0

The minimum supported Java version changes from 6 to 7.

• Change target Java version to 7 (#​2043)
• Put module-info.class into Multi-Release JAR folder (#​2013)
• Improve error message when abstract class cannot be constructed (#​1814)
• Support EnumMap deserialization (#​2071)
• Add LazilyParsedNumber default adapter (#​2060)
• Fix JsonReader.hasNext() returning true at end of document (#​2061)
• Remove Gradle build support. Build script was outdated and not actively
  maintained anymore (#​2063)
• Add GsonBuilder.disableJdkUnsafe() (#​1904)
• Add UPPER_CASE_WITH_UNDERSCORES in FieldNamingPolicy (#​2024)
• Fix failing to serialize Collection or Map with inaccessible constructor (#​1902)
• Improve TreeTypeAdapter thread-safety (#​1976)
• Fix Gson.newJsonWriter ignoring lenient and HTML-safe setting (#​1989)
• Delete unused LinkedHashTreeMap (#​1992)
• Make default adapters stricter; improve exception messages (#​2000)
• Fix FieldNamingPolicy.upperCaseFirstLetter uppercasing non-letter (#​2004)