Upgrade Jackson from 2.9.10 to 2.16.2

[mertant]

Why?

Issue:

• Intercom-java SDK is not compatible with recent versions of Jackson intercom/intercom-java#311

As described in the linked issue, if another dependency has Jackson as a transitive dependency and causes it to be updated to >2.15 in a project, then the Intercom HttpClient.readEntity method breaks (it begins to throw Jackson Databind UnrecognizedPropertyExceptions at runtime).

This PR attempts to upgrade the Jackson dependency of intercom-java & then fix the ObjectMapper as necessary.

See also:

• Update Jackson to 2.9.10 intercom/intercom-java#289

How?

1. Update Jackson from 2.9 to 2.15
   • Run tests, confirm they still pass.
2. Then update Jackson to 2.16
   • Run tests, confirm that they now begin to fail with: com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "type" (class io.intercom.api.TypedData), not marked as ignorable (0 known properties: ])
3. Fix usage of Jackson ObjectMapper:

• Try to add the necessary ObjectMapper configurations to MapperSupportso that it will (once again, as in older versions of Jackson) ignore any uncrecognized properties.
  • Set FAIL_ON_UNKNOWN_PROPERTIES to false
  • => This makes some of the tests pass; however, other tests still fail with com.fasterxml.jackson.databind.exc.InvalidDefinitionException: No serializer found for class io.intercom.api.TypedData and no properties discovered to create BeanSerializer (to avoid exception, disable SerializationFeature.FAIL_ON_EMPTY_BEANS) (through reference chain: io.intercom.api.User["companies"]
  • => Set FAIL_ON_EMPTY_BEANS to false
  • However, other tests till fail with e.g. java.lang.ClassCastException: io.intercom.api.TypedData cannot be cast to io.intercom.api.Segment.

It seems that something breaks the serialization of nested fields that are collections, such as tags and segments:

  "segments" : {
    "segments" : [ { } ],
    "type" : "segment.list"
  },
  "tags" : {
    "tags" : [ { } ],
    "type" : "tag.list"
  }

should be:

  "segments": {
    "type": "segment.list",
    "segments": [
      {
        "id": "5310d8e7598c9a0b24000002"
      }
    ]
  },
  "tags": {
    "type": "tag.list",
    "tags": [
      {
        "id": "202"
      }
    ]
  }

[mertant]

According to this, Intercom Java SDK will not be updated

intercom#311 (comment)

For the Java SDK, there are no planned updates at this time due to it being in maintenance mode as I said. So our recommendation is that you use regular API endpoints as opposed to the SDK wrapper.

[mertant]

Despite the above information, there now seems to be an upgrade to the official repository which upgrades jackson-databind to 2.17.2:

https://github.com/intercom/intercom-java/pull/321/files#diff-49a96e7eea8a94af862798a45174e6ac43eb4f8b4bd40759b5da63ba31ec3ef7R16

• 🌿 Fern Regeneration -- April 7, 2025 intercom/intercom-java#321

Therefore, I'm closing this PR.