Parse JSON in Java

How to parse a JSON string into an object and serialize (stringify) an object back to JSON in Java. Java has no built-in JSON; Jackson and Gson are the common libraries. Need to clean up the JSON first? Use the formatter & validator.

Parse JSON (string → object)

// Jackson
ObjectMapper mapper = new ObjectMapper();
JsonNode obj = mapper.readTree(text);

Stringify (object → JSON string)

String text = mapper.writerWithDefaultPrettyPrinter()
    .writeValueAsString(obj);

Frequently asked questions

How do I parse JSON in Java?

Java has no built-in JSON; Jackson and Gson are the common libraries. Parse with the snippet above; the result is a native object/map you can read.

How do I pretty-print JSON in Java?

Use the stringify snippet above with indentation, or paste your JSON into the formatter on this page.