Serializing a POJO based on a runtime whitelist of properties

Question

Is it possible to serialize a whitelisted subset of a POJO's properties (where the whitelist is known only at runtime) using Jackson?

All the solutions I know of so far (Views, @JsonIgnoreProperties etc.) are static, compile-time solutions.

Further, my backend returns results in the following format:

{
    "outcome": "SUCCESS", // an enum
    "message": "Success.", // a message for the developer
    "result": {
        // Some result that's different for each call
    }
}

So I am looking for a solution that can be applied to only parts of the object graph (like the contents of the result property).

Answer 1

You probably want to look at @JsonFilter.

See this tutorial on serializing only fields that meet some criteria which includes details of this, and a couple of other methods.

For completeness

@JsonFilter("pojo-filter")
class Pojo {
    public int foo;
}

FilterProvider filters = new SimpleFilterProvider()
    .addFilter("pojo-filter", new SimpleBeanPropertyFilter() {
        @Override
        protected boolean include(PropertyWriter writer) {
            return "foo".equals(writer.getName()) 
                ? Random.nextBoolean()
                : true;
        }
    });

new ObjectMapper().writer().filters(filters).write(new Pojo());

Globally you can use ObjectMapper.setFilterProvider