java
Unable to read JSON array in java
I have some JSON data which looks as follows {logs:[{"Log_Level":"Info","appTypeName":"WebNodeJS","Log_Thread":"1492451392226","Log_Component":"Monitoring.WebNodeJS","EntryType":"LogEvent","Log_Message":"Widget Render Time","Log_DateTime":"2017-04-17T17:49:52.226Z","DashboardId":"58f4f4f93b143a902a000022","DashboardName":"Dashboard","DashboardLoadTime":2830,"DashboardRefreshTime":855,"WidgetId":"58f4f4f93b143a902a000024","WidgetName":"Rich Text","WidgetQueryTime":0,"WidgetLoadTime":1888,"WidgetRenderTime":2,"WidgetType":"richtexteditor"}, {"Log_Level":"Info","appTypeName":"WebNodeJS","Log_Thread":"1492451392226","Log_Component":"Monitoring.WebNodeJS","EntryType":"LogEvent","Log_Message":"Widget Render Time","Log_DateTime":"2017-04-17T17:49:52.226Z","DashboardId":"58f4f4f93b143a902a000022","DashboardName":"Dashboard","DashboardLoadTime":2830,"DashboardRefreshTime":855,"WidgetId":"58f4f4f93b143a902a000027","WidgetName":"Top 10 Expensive Cases","WidgetQueryTime":508,"WidgetLoadTime":979,"WidgetRenderTime":86,"WidgetType":"chart/bar"}]} This is my code to read it. I would like to extract the individual elements WidgetLoadTime elements from it. However, it gives me the following error. public void preProcess() throws FileNotFoundException, IOException, ParseException { JSONParser parser = new JSONParser(); try { Object obj = parser.parse(new FileReader("file.json")); JSONObject jsonObject = (JSONObject) obj; System.out.println(jsonObject); // loop array JSONArray msg = (JSONArray) jsonObject.get(""); Iterator<String> iterator = msg.iterator(); while (iterator.hasNext()) { System.out.println(iterator.next()); } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } catch (ParseException e) { e.printStackTrace(); } }
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