jodd-json/src/main/java/jodd/json/JsonObject.java
public Double getDouble(final String key, final Double def) {
		Double val = getDouble(key);

		if (val == null) {
			if (map.containsKey(key)) {
				return null;
			}
			return def;
		}

		return val;
	}
public Double getDouble(final String key, final Double def) {
		Double val = getDouble(key);

		if (val == null) {
			if (map.containsKey(key)) {
				return null;
			}
			return def;
		}

		return val;
	}
Like {@link #getDouble(String)} but specifies a default value to return if there is no entry.