Method isNull

src/main/java/com/volmit/adapt/util/JSONObject.java:980–982

Determine if the value associated with the key is null or if there is no value. @param key A key string. @return true if there is no value associated with the key or if the value is the JSONObject.NULL object.

(String key)

     * is the JSONObject.NULL object.
     */
    public boolean isNull(String key) {
        return JSONObject.NULL.equals(this.opt(key));
    }

    /**
     * Get an enumeration of the keys of the JSONObject.