I have the below JSON , i need to remove all the keys which have null value
I have tried this
import java.util.Iterator;
import org.json.JSONException;
import org.json.JSONObject;
public class Remove {
public static void main(String[] args) throws JSONException {
String str = "{rn" +
" "videos": {rn" +
"
" }}";
JSONObject json_obj = new JSONObject(str);
JSONObject allKeys_json= json_obj.getJSONObject("videos");
Iterator<String> keys = allKeys_json.keys();
while( keys.hasNext() ) {
String keyanme = (String)keys.next();
String keyvalue = allKeys_json.getString(keyanme);
if(keyvalue.contains("null"))
{
System.out.println(keyanme+"t"+keyvalue);
json_obj.remove(keyanme);
}
}
System.out.println(allKeys_json);
}
}
but the actual json is unaffected , could you please tell me how to do this .
Answer
If it’s only about manipulating a string which structure you know well a solution would be to use some regex
str.replaceAll(".*": null(,)?\r\n", "");
It could be easier to find a good regex than to invest time in building a model that could be used by Jackson.
Three notes:
the code above doesn’t figure out which is the last line and adapt the json accordingly.
the pattern should be compiled separately.
org.json is very inefficient compared to Jackson.