Jackson Release 2.18

Jackson Version 2.18 development is planned to start in March, 2024.

This wiki page gives a list of links to all changes (with brief descriptions) that will be included, as well as about original plans for bigger changes (and in some cases changes to plans, postponing).

Status

Branch is waiting to be created.

Patches

No release yet

Documentation

Articles, Blog posts

Changes, compatibility

Compatibility: platform requirements

JDK

Same as Jackson 2.17

Changes, behavior

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Major focus areas, features included

The Focus!

• REWRITE BEAN PROPERTY INTROSPECTION -- AND ESPECIALLY CREATOR INTROSPECTION

Most Wanted features planned

• #512: Add @JsonWrapped
  • Matching annotations issue: annotations#42

Functionality improvements

• Fix handling of null Type Id with JsonGenerator.writeTypePrefix() (and databind-level TypeIdSerializer)
  • Issue: databind#4407
  • Background:
    • See databind#4354 for immediate problem with null type id
    • See databind#3307 that seems like regression

Performance improvements

• More optimized JsonParser.getFloatValue() / JsonParser.getDoubleValue(): avoid String creation when calling FastDoubleParser
  • Issue reported: core#1229: Add char[] versions for NumberInput parseFloat, parseDouble, parseBigInteger
  • possible regression for "Deferred" number parsing

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Full Change list

Changes, core

Annotations

Streaming

• #1230: Improve performance of float and double parsing from TextBuffer
• #1251: InternCache - replace synchronized with ReentrantLock
• #1252: ThreadLocalBufferManager replace synchronized with ReentrantLock
• #1257: Increase InternCache default max size from 100 to 200
• #1262: Add diagnostic method pooledCount() in RecyclerPool
• #1264: Rename shaded ch.randelshofer:fastdoubleparser classes to prevent use by downstream consumers
• #1266: Change default recycler pool to bewConcurrentDequePool() in 2.18
• #1267: Add back Java 22 optimisation in FastDoubleParser
• #1271: Deprecate LockFreePool implementation in 2.18 (remove from 3.0)
• #1277: Add back Java 22 optimisation in FastDoubleParser

Databind

• #2977: Incompatible FAIL_ON_MISSING_PRIMITIVE_PROPERTIES and field level @JsonProperty
• #3241: constructorDetector seems to invalidate defaultSetterInfo for nullability
• #4119: Exception when deserialization uses a record with a constructor property with access=READ_ONLY
• #4452: @JsonProperty not serializing field names properly on @JsonCreator in Record
• #4453: Allow JSON Integer to deserialize into a single-arg constructor of parameter type double
• #4456: Rework locking in DeserializerCache
• #4458: Rework synchronized block from BeanDeserializerBase
• #4464: When Include.NON_DEFAULT setting is used, isEmpty() method is not called on the serializer
• #4472: Rework synchronized block in TypeDeserializerBase
• #4483: Remove final on method BeanSerializer.serialize()
• #4515: Rewrite Bean Property Introspection logic in Jackson 2.x

Changes, data formats

CSV

• #468: Remove synchronization from CsvMapper
• #469: Allow CSV to differentiate between null and empty fields (foo,,bar vs. foo,"",bar)

Protobuf

• #484: Rework synchronization in ProtobufMapper

Changes, Other modules

JAXB Annotations

• #233: Tolerate JAX-RS 2.2 in jackson-module-jaxb-annotations so that it can be deployed in Liberty alongside features which use 2.2

Changes, JVM Languages

Kotlin

Scala

Changes, Providers

Changes, other

Jackson-jr

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