Filed under note to self as I keep forgetting this. Here’s a very simple way to pretty print a com.fasterxml.jackson.databind.JsonNode:

public String prettyPrintJsonString(JsonNode jsonNode) {
    try {
        ObjectMapper mapper = new ObjectMapper();
        Object json = mapper.readValue(jsonNode.toString(), Object.class);
        return mapper.writerWithDefaultPrettyPrinter().writeValueAsString(json);
    } catch (Exception e) {
        return "Sorry, pretty print didn't work";

The prettyPrintJsonString(...) method above would print out example JsonNode here…

JsonNode example = Json.newObject()
                       .put("name", "Example")
                       .set("obj", Json.newObject());

…as this:

    "name": "Example",
    "obj": {}

This a simple trick, but I forget things.