Java - JSON Null Exception

exception, java, json, null

Solution

For me this works with json-lib-2.3-jdk15:

String json = "{\"prop1\":\"val1\", \"prop2\":123, \"prop3\":null}";
JSONObject jsonObject = JSONObject.fromObject(json);
HashMap<String, Object> map = (HashMap<String, Object>) JSONObject.toBean(jsonObject, HashMap.class);

Actually the `null` value becomes an instance of `JSONNull`.

`JSONNull` is equivalent to the value that JavaScript calls `null`, whilst Java's `null` is equivalent to the value that JavaScript calls `undefined`.

Problem

I'm using JSON to deserialize an input string that contains a `null` value for certain hashmap property. Does anyone have any clue why this exception occurs ? Is it possible that `null` is not accepted as a value Is this configurable somehow ? input sample: ``` {"prop1":"val1", "prop2":123, "prop3":null} ``` stacktrace: ``` net.sf.json.JSONException: null object at net.sf.json.JSONObject.verifyIsNull(JSONObject.java:2856) at net.sf.json.JSONObject.isEmpty(JSONObject.java:2212) ``` Thanks.

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