I have code in a method that I ported that now throws JSONException in my newly created java code.
Below does not work as it used to:
if (theEvent.getString("plugin")== null)
{
processNonPluginEvent(theEvent);
return;
}
I found out using
org.json.JSONObject
behaves differently than it did on my old code using a different JSON library in c#. The above code always gets caught by an exception. In my old code if a key didn't exist it would return null. Do I really have to catch for that exception in the event the key doesn't exsist? or is there another way I have not yet discovered to tell if my org.json.JSONObject has a key or not in it?
for reference the old c# code looked like:
if (theEvent["plugin"] == null)
{
processNonPluginEvent(theEvent);
return;开发者_如何学JAVA
}
Assuming you are using the code from this library, I believe you want:
if (!theEvent.has("plugin"))
{
processNonPluginEvent(theEvent);
return;
}
Check out the documentation for the JSONObject
class:
http://www.json.org/javadoc/org/json/JSONObject.html
Also, all classes from the library are documented here.
To see if the JSONObject
has a key, use the JSONObject.has(String key)
function.
e.g.
if (!theEvent.has("plugin")) {
processNonPluginEvent(theEvent);
}
From the JavaDoc, the has()
function:
Determine if the JSONObject contains a specific key.
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