Jackson3 Changes

Proposed Jackson 3.0 changes

JVM/JDK Compatibility

• Jackson 3.x will require and be based on Java 8
  • with possible exception of jackson-core and jackson-annotations (?)

Module structure

• Embed some/all Java8 modules
  • Embed "parameter names", "datatypes" (Optional)
  • Need to think of Java 8 date/time module (size)

Things to Remove

Major features

1. Dataformat auto-detection (most in streaming, some in databind)
   • supported by some formats, but complicated to make work at higher level
2. Old JSON Schema generation that builds JsonNode (already deprecated)
   • Not actively maintained since at least 2.4, deprecated by visitor-based approach since then

Features

MapperFeature:

• USE_STD_BEAN_NAMING: should always be used, no need for old slightly differing algorithm

Entities

• ContextualSerializer / ContextualDeserializer, ResolvableSerializer / ResolvableDeserializer
  • just embed as part of JsonSerializer / JsonDeserializer, with no-op implementation

Major API change areas:

• JsonNode needs major rework; can do binary-incompatible return value changes

Changes to defaults

(will require wiki sub-page)

• MapperFeature
  • SORT_PROPERTIES_ALPHABETICALLY: default to true (false really doesn't make much sense since it is unstable, and arbitrary based on JVM/JDK)
• DeserializationFeature
  • READ_ENUMS_USING_TO_STRING: default to true (instead of false that relies on name())
  • FAIL_ON_UNKNOWN_PROPERTIES: default to false? (TOP REQUEST by users)
• SerializationFeature
  • FAIL_ON_EMPTY_BEANS: default to false
• Other
  • Check defaults of date/time handling