Jackson Release 2.9

Version 2.9 development is on-going, as of October 2016, with tentative goal of getting RC1 out during December 2016.

New Modules, status changes

Changes: compatibility

java.sql.Date

As per databind#219 java.sql.Date will finally use same "timestamp-or-String" determination as java.util.Date and java.util.Calendar. This means that with vanilla, unchanged settings, values will be serialized as numeric timestamps. Note that the default String serialization will still default to java.sql.Date.String(), and not to default formatting java.util.Date uses.

Major features of 2.9

Implemented

1. Add separate exception type for "pojo configuration problem" (InvalidDefinitionException), distinct from "json input" problem; in general to distinguish between bad configuration (server-side issue) and bad data (client issue) #1356
2. Per-property custom serialization inclusion (@JsonInclude(value=Include.CUSTOM, valueFilter=MyExcluder.class) #888
3. Per-property overwrite-vs-merge annotation/handling, to allow for merging of configuration information (for example) #1399
   • note: on-going work to increase coverage; some types (arrays, tree nodes) not yet supported
4. Ability to override handling of null for deserialization #1402

Under construction

1. Aliases, to allow migration: alternate property id names to accept (but not write) #1029

Planned

1. DeserializationFeature to automatically verify that value bound is full value and there is no trailing junk in input ("whole value verification")
2. Non-blocking JSON/Smile parser?
3. Ability to force "inject-only" variant of @JacksonInject #1381 -- also solves a few related issues wrt un-deserializable injectable values (which are common)
4. Allow pre-defining Object Ids; pluggable Object Id converters? #693
5. A way to force a supertype as type id to use during serialization: this is needed to avoid deserialization problems for things like concrete Hibernate collection type. #789
6. "Safe" ObjectReader, ObjectWriter; that is, ones that does NOT throw checked exceptions (wrap IOExceptions), to work better with Java 8 Streams #779

And possibly

• Protobuf: Schema building by hand
• Comma-separated "ints in a String" #1242
• Support for @JsonIncludeProperties (opposite of @JsonIgnoreProperties) #1296

Changes likely to be postponed

Some things that we are aware of but that very likely get postponed:

• @JsonUnwrapped improvements, which need major rewrite of unwrapped deserialization:
  • Support for @JsonUnwrapped as @JsonCreator parameter
  • Catching "unknown" properties
• Rewrite of property/creator introspection code, to resolve most open issues wrt Creator auto-detection and name-detection

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Change list

Changes, core

Annotations

• #103: Add JsonInclude.Include.CUSTOM, properties for specifying filter(s) to use
• #104: Add new properties in @JsonSetter: merge, null/contentNulls
• #105: Add @JsonFormat.lenient to allow configuring lenience of date/time deserializers
• #108: Allow @JsonValue on fields
• #109: Add enabled for @JsonAnyGetter, @JsonAnySetter, to allow disabling via mix-ins
• #113: Add @JsonMerge to support (deep) merging of properties
• Allow use of @JsonView on classes, to specify Default View to use on non-annotated properties.

Streaming

• #17: Add 'JsonGenerator.writeString(Reader r, int charLength)'
• #312: Add JsonProcessingException.clearLocation() to allow clearing possibly security-sensitive information
• #323: Add JsonParser.ALLOW_TRAILING_COMMA to work for Arrays and Objects
• #325: DataInput backed parser should handle EOFException at end of doc
• #340: Make WriterBasedJsonGenerator non-final
• #356: Improve indication of "source reference" in JsonLocation wrt byte[],char[]

Databind

• #219: SqlDateSerializer does not obey SerializationConfig.Feature.WRITE_DATES_AS_TIMESTAMPS
• #476: Allow "Serialize as POJO" using @JsonFormat(shape=Shape.OBJECT) class annotation
• #507: Support for default @JsonView for a class
• #888: Allow specifying custom exclusion comparator via @JsonInclude, using JsonInclude.Include.CUSTOM
• #1035: @JsonAnySetter assumes key of String, does not consider declared type
• #1284: Make StdKeySerializers use new JsonGenerator.writeFieldId() for int/long keys
• #1320: Add ObjectNode.put(String, BigInteger)
• #1341: DeserializationFeature.FAIL_ON_MISSING_EXTERNAL_TYPE_ID_PROPERTY
• #1347: Extend ObjectMapper.configOverrides() to allow changing visibility rules
• #1356: Differentiate between input and code exceptions on deserialization
• #1369: Improve @JsonCreator detection via AnnotationIntrospector by passing MappingConfig
• #1371: Add MapperFeature.INFER_CREATOR_FROM_CONSTRUCTOR_PROPERTIES to allow disabling use of @CreatorProperties as explicit @JsonCreator equivalent
• #1376: Add ability to disable JsonAnySetter/JsonAnyGetter via mixin
• #1399: Add support for @JsonSetter(merge=OptBoolean.TRUE) to allow "deep update"
• #1406: ObjectMapper.readTree() methods do not return null on end-of-input
• #1407: @JsonFormat.pattern is ignored for java.sql.Date valued properties
• #1428: Allow @JsonValue on a field, not just getter
• #1454: Support @JsonFormat.lenient for java.util.Date, java.util.Calendar

Changes, data formats

Avro

• #15: Add a way to produce "file" style Avro output

CSV

• #127: Add CsvGenerator.Feature.ALWAYS_QUOTE_EMPTY_STRINGS to allow forced quoting of empty Strings
• #130: Add fluent addColumns operation to CsvSchema.Builder
• #139: Add CsvParser.Feature.ALLOW_TRAILING_COMMA to allow enforcing strict handling

Properties

• #3: Write into Properties instance (factory, mapper) using JavaPropsMapper.writeValue() with Properties and JavaPropsMapper.writeValueAsProperties()
• #4: Allow binding from Properties instance

YAML

• #76: Add YAMLGenerator.Feature.LITERAL_BLOCK_STYLE for String output

Changes, other modules

JSON Schema

• #119: dependencies property should not be an Array but Object