JSON Java check element is a JSONArray or JSONObject
How to check whether an element is a JSONArray or JSONObject. I wrote the code to check,
if(jsonObject.getJSONObject("Category").getClass().isArray()) {
} else {
}
In this case if the element 'category' is JSONObject then it work fine but if it contains an array then it throw exception: JSONArray cannot be converted to JSONObject. Please help. Thanks.
Yes, this is because the getJSONObject("category")
will try to convert that String
to a JSONObject what which will throw a JSONException
. You should do the following:
Check if that object is a JSONObject
by using:
JSONObject category=jsonObject.optJSONObject("Category");
which will return a JSONObject
or null
if the category
object is not a json object.
Then you do the following:
JSONArray categories;
if(category == null)
categories=jsonObject.optJSONArray("Category");
which will return your JSONArray
or null if it is not a valid JSONArray
.
Even though you have got your answer, but still it can help other users...
if (Law.get("LawSet") instanceof JSONObject)
{
JSONObject Lawset = Law.getJSONObject("LawSet");
}
else if (Law.get("LawSet") instanceof JSONArray)
{
JSONArray Lawset = Law.getJSONArray("LawSet");
}
Here Law
is other JSONObject
and LawSet
is the key which you want to find as JSONObject or JSONArray
.
String data = "{ ... }";
Object json = new JSONTokener(data).nextValue();
if (json instanceof JSONObject)
//you have an object
else if (json instanceof JSONArray)
//you have an array
tokenizer is able to return more types: http://developer.android.com/reference/org/json/JSONTokener.html#nextValue()
if (element instanceof JSONObject) {
Map<String, Object> map = json2Java.getMap(element
.toString());
if (logger.isDebugEnabled()) {
logger.debug("Key=" + key + " JSONObject, Values="
+ element);
}
for (Entry<String, Object> entry : map.entrySet()) {
if (logger.isDebugEnabled()) {
logger.debug(entry.getKey() + "/"
+ entry.getValue());
}
jsonMap.put(entry.getKey(), entry.getValue());
}
}
You can use instanceof
to check the type of the result that you get. Then you can handle it as you wish.
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