Please provide a way to clone an ObjectMapper

[rzio]

We need a way to clone an ObjectMapper. The user case is:
At some times we need a ObjectMapper which has a slightly different configuration that the one that we use though the system.

In Jackson 1.9.1 we did this by
ObjectMapper o1= new ObjectMapper()
.setSerializationConfig(objectMapper.getSerializationConfig()
.with(SerializationConfig.Feature.INDENT_OUTPUT));

I couldn't find a way to reproduce this in Jackson 2.

We cannot use ObjectReader/ObjectWriter for this, since we use both databinding and the TreeModel and ObjectWriter doesn't have support for TreeModel.

[cowtowncoder]

Right, 2.0 sort of hides access to serialization/deserialization config objects.
I'll have to think of best way to do this; one possibility would be to just implement clone() properly, another to have something similar but named explicitly (copyOf())

[rzio]

ObjectMapper o1= objectMapper.clone().configure(SerializationFeature.INDENT_OUTPUT));

or
ObjectMapper o1= ObjectMapper.copyOf(objectMapper).configure(SerializationFeature.INDENT_OUTPUT));

Both seem reasonable to me :)

[cowtowncoder]

Right, those seem like obvious choices. I may ask others on dev list for their input just for fun.

[cowtowncoder]

Implemented as 'ObjectMapper.copy()'. Required quite a bit more work than I expected; had to add JsonFactory.copy() as well, tested etc. But should work more reliably than the old method, as well; i.e. copy all state, unshare.