Method putOnce

src/main/java/com/mcbans/plugin/org/json/JSONObject.java:1112–1120

Put a key/value pair in the JSONObject, but only if the key and the value are both non-null, and only if there is not already a member with that name. @param key @param value @return his. @throws JSONException if the key is a duplicate

(String key, Object value)

     * @throws JSONException if the key is a duplicate
     */
    public JSONObject putOnce(String key, Object value) throws JSONException {
        if (key != null && value != null) {
            if (opt(key) != null) {
                throw new JSONException("Duplicate key \"" + key + "\"");
            }
            put(key, value);
        }
        return this;
    }


    /**