Question

if(jsonArray.getJSONObject(i).get("SECNO").toString()!=null && jsonArray.getJSONObject(i).get("SECNO").toString().trim()!="")
                        appointment.mSecNo =Integer.parseInt(jsonArray.getJSONObject(i).get("SECNO").toString());
                    else
                        appointment.mSecNo = -1;

In the previouse lines, when the value of jsonArray.getJSONObject(i).get("SECNO").toString() equales to ” it doesn’t be caught by the if statement ..

and I get this error message .. can't parse '' to integer

Answer 1

Don’t use == or != to compare strings in Java – it only compares the references, not the contents of the strings. Also, I doubt that toString would ever return null. I suspect you want:

Foo x = jsonArray.getJSONObject(i).get("SECNO");
if (x != null && x.toString().trim().length() > 0)

(I don’t know what the type of jsonArray.getJSONObject(i).get("SECNO") would be, hence the Foo.)

In this particular case I’ve used length() > 0 to detect a non-empty string – but for more general equality, you’d want to use equals, so an alternative is:

if (x != null && !x.toString().trim().equals(""))