chriskilding / jackson-dataformat-ron Goto Github PK

The Jackson Core superclasses have some aspects that make them awkward to specialise for RON. Ask for changes in upstream to make this easier.

• JsonStreamContext#inArray() is final. We need to override this, so ask for the final modifier to be removed.
• JsonStreamContext#inRoot() is final. We need to override this, so ask for the final modifier to be removed.
• JsonStreamContext#inObject() is final. We need to override this, so ask for the final modifier to be removed.
• JsonParser#nextToken() returns JsonToken which is an enum. This means it can't be extended to add RON concepts like START_TUPLE/END_TUPLE. So we have to provide the awkward nextRONToken method adjacent to it. Ask for this to be changed into something that can handle extension, e.g. make JsonToken an interface.
• MapperFeature is an enum. This means it can't be extended to add RON concepts (like say WRITE_STRUCT_NAMES) to the RONMapper.

How can we address RON field ordering in this library?

To do:

• Use a Java Map subtype that preserves order e.g. LinkedHashMap

Find a way to support enums that contain fields in the mapper.

Example:

Foo(1, true)

The JSON ObjectMapper does not support these, so there is no prior code in Jackson to fall back on.

Add a RON write feature (in the style of JsonWriteFeatures) which lets the user decide whether the generator should write trailing commas or not.

Add a boolean property to RONStructSerializer which allows the user to decide whether struct names are written. Expose this in the Mapper API as a write feature.

Add support for binary/byte arrays

Tuples are difficult because Java doesn't natively support them. Observing RON field ordering in Java is also an issue. Is there a way to make tuples work in the RONMapper (reading or writing)?

Some options:

• Read tuples to Collection<Object>
  • Optionally allow some specialisation of the generic type if all elements have some commonality e.g. Collection<Number>
• Use a 3rd party tuple library like javatuples
• Wait for JDK to add native tuples one day