How to convert hashmap to JSON object in Java

Question

How to convert or cast hashmap to JSON object in Java, and again convert JSON object to JSON string?

Answer 1

Example using json

Map data = new HashMap();
    data.put( "name", "Mars" );
    data.put( "age", 32 );
    data.put( "city", "NY" );
    JSONObject json = new JSONObject();
    json.putAll( data );
    System.out.printf( "JSON: %s", json.toString(2) );

output::

JSON: {
  "age": 32,
  "name": "Mars",
  "city": "NY"
}

You can also try to use Google's GSON.Google's GSON is the best library available to convert Java Objects into their JSON representation.

http://code.google.com/p/google-gson/