Can not deserialize instance of java.util.ArrayList out of FIELD_NAME token

[slvs]

I'm using json-patch-1.9, and the following simple code doesn't work:

        String origJson = "{\"id\":1}";
        String newJson =  "{\"id\":1}";
        ObjectMapper mapper = new ObjectMapper();
        JsonNode origNode = mapper.readTree(origJson);
        JsonNode newNode = mapper.readTree(newJson);
        JsonPatch patchNew = JsonPatch.fromJson(newNode);
        JsonNode diffs = patchNew.apply(origNode);

The call to JsonPatch.fromJson(newNode) throws the following exception:

com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of java.util.ArrayList out of FIELD_NAME token

Any idea what is wrong?

[ghost]

I assume the JsonPatch expects json that looks like [{"op": "add", "path": "/id", "value": 1}]. Described at: https://tools.ietf.org/html/rfc6902

Maybe you are thinking of JsonMergePatch? https://tools.ietf.org/html/rfc7386

Which uses the JsonMergePatch.fromJson function.

[fge]

Exactly what @jhuffaker said; here you are trying to use a JSON Merge Patch, not a JSON Patch.