Question

I am using JSONObject to build a JSON response. The problem I’m facing is how to handle the exception that .put() throws. I surrounded my code with a try catch, but I want to output JSON in my catch as well. I’ve been doing this by hand as seen below, but this seems prone to errors.What is the right way to handle this exception?

try{
    myResponse.put("successful",true);
    resp.getOutputStream().print(myeResponse.toString());
} catch (JSONException e) {
    resp.getOutputStream().print("{\"successful\":false, \"error\":\"Changes could not be saved.  Please reload the page and try again.\"}");
}

Answer 1

What you need to figure out is when the put() method of JSONObject would throw JSONException.

From the Javadoc

public JSONObject put(java.lang.String key,
                      boolean value)
               throws JSONException

Put a key/boolean pair in the JSONObject.

Parameters:
    key - A key string.
    value - A boolean which is the value. 
Returns:
    this. 
Throws:
    JSONException - If the key is null.

So, all you need to take care is that your key is not null which would surely be the case because your key is "successful".