Jackson Work in Progress

Jackson WIP

This page is a "living document" of on-going work, mostly by @cowtowncoder (Tatu), although other committers are welcome to update it as well.

Contents are divided in 3 sections, of actionable (*) things:

1. Urgent things -- security problems, correctness (corruption), reliability (threading/concurrency)
2. Simple things -- low(er) hanging fruits that are likely easily fixable but also important (i.e. non-trivial)
3. Important -- things that important strategically, or highly "voted", but that are more involved to fix/implement.

as well as one "Recently Completed" addendum.

Note that this page does NOT contain "Big Ideas" for Jackson 3.0: these are covered on separate JSTEP page.

(*) actionable meaning, in general, that progress is only/mostly limited by time available and not by inherent difficulty, or lack of design or ideas of how to tackle the need.

Last updates

• 20-Feb-2019, tatu: Fixes, fixes, fixes
• 15-Dec-2018, tatu: With release 2.9.8, trim down "recently completed"
• 29-Oct-2018, tatu: Create the initial version

Urgent things

3.0

2.10

• https://github.com/FasterXML/jackson-core/issues/479: rewrite BufferRecycler fix
• https://github.com/FasterXML/jackson-core/issues/498: better Java 9+ module name support with moditect Maven plug-in (https://github.com/moditect/moditect)

2.9

Simple Things

3.0

• Annotations
  • https://github.com/FasterXML/jackson-annotations/pull/149: Use @Repeated on annotations like JsonSubtypes.Type
• Streaming
  • Remove mutability of JsonGenerator: NOTE, CharacterEscapes hard (due to JSONP); pretty-printer easier, max-non-escaped easy too? Features?
  • https://github.com/FasterXML/jackson-core/issues/507: Escape forward slash in Strings by default (but also allow change)
• Databind
• Formats
  • https://github.com/FasterXML/jackson-dataformats-text/pull/106 (YAML): update to SnakeYAML engine

2.10

• Streaming
  • https://github.com/FasterXML/jackson-core/issues/517: add JsonGenerator.writeStartObject(Object, int)
• Databind
  • https://github.com/FasterXML/jackson-databind/issues/2253: support multiple properties with @JsonRootName, unwap;
• Dataformats, binary
  • https://github.com/FasterXML/jackson-dataformats-binary/issues/73: (protobuf) References to nested types
• Dataformats, text
  • https://github.com/FasterXML/jackson-dataformat-xml/issues/311: (XML) namespace binding issue
  • https://github.com/FasterXML/jackson-dataformat-xml/issues/325: (XML) polymorphic ids
  • https://github.com/FasterXML/jackson-dataformats-text/issues/90: (YAML) base64 problems
  • https://github.com/FasterXML/jackson-dataformats-text/issues/91: (Properties) escaping or not

2.9

None.

Important Things

3.0

• Finish partial rewrite of JsonFormat.Shape handling to support ALL changes (POJO to/from non-POJO), for types AND properties
• https://github.com/FasterXML/jackson-databind/issues/2246: "Iterable" JavaType for Stream, Iterator etc
• https://github.com/FasterXML/jackson-core/issues/485: Add vanilla version for generators, to optimize handling

2.10

Databind

• https://github.com/FasterXML/jackson-core/issues/500: allow "optional padding" for base64 (not just required/not-allowed choices)
• https://github.com/FasterXML/jackson-databind/issues/2195: Add abstraction for ClassNameValidator, for default typing, @JsonTypeInfo
• https://github.com/FasterXML/jackson-databind/issues/2237: (XML) JsonNode improvements.
• https://github.com/FasterXML/jackson-databind/issues/18: Make JsonNode JDK Serializable

Other

• https://github.com/FasterXML/jackson-dataformats-text/issues/115: (CSV) JsonProperty.index is not honored by CsvSchema builder
• https://github.com/FasterXML/jackson-jr/issues/32: (Jackson-jr) Support subset of Jackson annotations (@JsonProperty et al)
• https://github.com/FasterXML/jackson-dataformats-text/issues/100: (Properties) -- allow support for Prefixes

2.9

Big Ideas

Note: many Big Ideas now included on JSTEP page.

But a scratchpad for stuff can be retained...

• Add new JsonToken type for "Native Object Id Reference", mostly for YAML?

Documentation

(NOTE: need to include in some better way, but for now just need a place to add ideas)

Another dimension of things to work is... documentation.

• Rewrite jackson-databind README to make it plain that JSON is NOT the only supported format: add examples, links
• Write blog entries about:
  1. How does property introspection COMPLETELY work
  2. Simple "untyped" serialization with Guava ImmutableMap/ImmutableList

---

Recently completed

Here are things since December 2018, after release of 2.9.8 (except for 3.0 some earlier too)

2.9

• https://github.com/FasterXML/jackson-datatype-json-org/issues/15 (org.json): Misleading exception when trying to deserialize JSON String as org.json.JSONArray value (07-Jan-2019)
• https://github.com/FasterXML/jackson-databind/issues/1408: Sync on getBounds() (15-Jan-2019)
• https://github.com/FasterXML/jackson-core/pull/510: ArrayIndexOutOfBounds for unquoted names, reader-parser. (16-Jan-2019)
• https://github.com/FasterXML/jackson-databind/issues/2221: DeserializationProblemHandler, type Void.class (17-Jan-2019)
• https://github.com/FasterXML/jackson-databind/pull/2227: Enum exception typo (18-Jan-2019)
• https://github.com/FasterXML/jackson-modules-base/pull/70: Afterburner, MapperFeature.ALLOW_COERCION_OF_SCALARS (28-Jan-2019)
• https://github.com/FasterXML/jackson-dataformats-text/issues/63 (yaml): Null Object Ids written.
• https://github.com/FasterXML/jackson-core/issues/516: _inputPtr OBO (13-Feb-2019)
• https://github.com/FasterXML/jackson-dataformats-text/issues/122: CSV. readValues(null), infinite loop (18-Feb-2019)
• https://github.com/FasterXML/jackson-modules-base/issues/49: (afterburner) Locking of class loading (16-Feb-2019)
• https://github.com/FasterXML/jackson-dataformats-text/issues/123: (YAML) Problem with ObjectId (20-Feb-2019)
• https://github.com/FasterXML/jackson-dataformat-xml/issues/333: (XML) no Decorator applied

2.10

• https://github.com/FasterXML/jackson-databind/issues/2223: Add missingNode() method in JsonNodeFactory (11-Jan-2019)
• https://github.com/FasterXML/jackson-dataformats-binary/issues/155: Only flush outputs when FLUSH_PASSED_TO_STREAM is allowed (14-Jan-2019)
• https://github.com/FasterXML/jackson-core/issues/464: Add "maximum unescaped char" limit option in JsonFactory.builder() (14-Jan-2019)
• https://github.com/FasterXML/jackson-databind/issues/2189: Bounds checks (int, long) for TreeTraversingParser (and verify TokenBuffer's too) (16-Jan-2019)
• https://github.com/FasterXML/jackson-databind/issues/2211: change in ObjectMapper.readTree() for "no content" return value in 2.9 (24-Jan-2019)
• (hibernate) https://github.com/FasterXML/jackson-datatype-hibernate/issues/125: Ignore missing entities when lazy loading is enabled, if (newly added) Feature.WRITE_MISSING_ENTITIES_AS_NULL is enabled (24-Jan-2019)
• https://github.com/FasterXML/jackson-databind/issues/2220: avoid short-circuit for ObjectMapper.convertValue() (25-Jan-2019)
• https://github.com/FasterXML/jackson-databind/pull/2241: Add PropertyNamingStrategy.LOWER_DOT_CASE (04-Feb-2019)
• https://github.com/FasterXML/jackson-databind/issues/1675: Remove IOException from String/byte[] sourced parse methods (04-Feb-2019)
• https://github.com/FasterXML/jackson-databind/issues/2236: Double.NaN, polymorphic type info due to serialization as String (08-Feb-2019)
• https://github.com/FasterXML/jackson-core/pull/518: Perf improvement for int/long decoding from `char-backed sources

3.0

• https://github.com/FasterXML/jackson-databind/issues/2176: add JsonMapper.shared() (and ditto for other mappers) (10-Dec-2018)
• https://github.com/FasterXML/jackson-databind/pull/2196: Type safety wrt TypeReference, ObjectMapper.readValue() (10-Jan-2019)