/**
* Construct a JSONObject from a subset of another JSONObject. An array of strings is used to
* identify the keys that should be copied. Missing keys are ignored.
*
* @param jo A JSONObject.
* @param sa An array of strings.
* @throws JSONException If a value is a non-finite number.
*/
public JSONObject(JSONObject jo, String[] sa) throws JSONException {
this();
for (int i = 0; i < sa.length; i += 1) {
putOpt(sa[i], jo.opt(sa[i]));
}
}
