public JSONObject increment(String key) throws JSONException {
		Object value = this.opt(key);
		if (value == null) {
			this.put(key, 1);
		} else if (value instanceof Integer) {
			this.put(key, ((Integer) value).intValue() + 1);
		} else if (value instanceof Long) {
			this.put(key, ((Long) value).longValue() + 1);
		} else if (value instanceof Double) {
			this.put(key, ((Double) value).doubleValue() + 1);
		} else if (value instanceof Float) {
			this.put(key, ((Float) value).floatValue() + 1);
		} else {
			throw new JSONException("Unable to increment [" + quote(key) + "].");
		}
		return this;
	}