Ability to annotate required properties

Is this same as JACKSON-538?

Wow. What a long thread

To answer your question: I am not looking for property validation (as JACKSON-538 seems to imply). I am looking for Jackson to ensure that the property exists. Property existence is not the same thing as property value. For example, a property may be allowed to have a null value so long as the property is explicitly set. Furthermore, @NotNull sounds weird for primitive types that are not assigned a null value even if they're missing.

PS: I don't like the name @JsonMandatory. I'd prefer adding an attribute to @JsonProperty which indicates whether it is required.

Actually, I take it to only mean same as what you mean; i.e. existence check.

I actually kind of like @JsonMandatory, although am open to alternative names.
I am not quite sure of a new property for @JsonProperty; although if it is possible to just omit name, to do:

@JsonProperty(required=true)

(and let name be auto-detected)

perhaps it actually would work well.

I now also see what you mean, wrt JACKSON-538: discussion is pretty long-winded, and I forgot most of it, just looking at title.

So I will leave this is the thing to track possible feature – in fact, I have slowly started thinking that this would be a valuable addition, as well: and precisely not as (full) validation, but just sort of constraints to data-binding. Anything more elaborate should be added via generic post-processing functionality, for which a separate RFE is warranted.

Quick update: there is now "required" property in @JsonProperty (for 2.0 annotations) – but adding support for it turns out more difficult than anticipated. This because there is no place for keeping track of state during deserialization; deserializers are state-less (to allow concurrency, reuse), and adding hierarchic state in DeserializationContext is non-trivial undertaking.
This just means that we will try to work on this for 2.1, but it will not make it to 2.0.