Get java.lang.String cannot be converted to JSONObject when trying to retrieve value from a specific column

Question

Seriously, I have no idea what's was going wrong here.

This is my work_details table

Assume the ID is 3 , so I want to retrieve the timeIn and timeOut which twd belongs to 3 (In my code, I want to retrieve one row only).

  public void RetrieveTotalHours( final String ID) // ID(twd)=3
    {
        class GetHours extends AsyncTask<Void,Void,String> {
            ProgressDialog loading;
            @Override
            protected void onPreExecute() {
                super.onPreExecute();
                loading = ProgressDialog.show(getActivity(),"Fetching...","Wait...",false,false);
            }

            @Override
            protected void onPostExecute(String s) {
                super.onPostExecute(s);
                loading.dismiss();
                showHours(s);
            }

            @Override
            protected String doInBackground(Void... params) {
                RequestHandler rh = new RequestHandler();
                String s = rh.sendGetRequestParam(Configs.RETRIEVE_HOURS,ID);
                return s;
            }
        }
        GetHours ge = new GetHours();
        ge.execute();

    }
    private void showHours(String json) {
        try {
            JSONObject jsonObject = new JSONObject(json);
            JSONArray result = jsonObject.getJSONArray(Configs.TAG_JSON_ARRAY);
            JSONObject c = result.getJSONObject(0);
            String MiNtimeIn = c.getString(Configs.TAG_IN); 
            String MaXtimeOut=c.getString(Configs.TAG_OUT);
            Log.e("min", MiNtimeIn);
            Log.e("max", MiNtimeOut);

    }

Retrieve_hours.php

 <?php
  define('HOST','127.0.0.1:3307');
  define('USER','root');
  define('PASS','');
  define('DB','androiddb');

  $con = mysqli_connect(HOST,USER,PASS,DB) or die('unable to connect');

  $twd= $_GET['id'];

 $sql = "select * FROM work_details WHERE twd = '".$twd."'";

  $res = mysqli_query($con,$sql);

  $result=array();


  while($row=mysqli_fetch_array($res)){
      array_push($result,array('id'=>$row[0],'project'=>$row[1],'work_description'=>$row[2],'percentage'=>$row[3],'timeIn'=>$row[4],'timeOut'=>$row[5]));
  }

  echo (json_encode(array("result"=>$result)));

mysqli_close($con);

?>

I can see there are something display on the log . But when I specific the column, I will get this annoying error.

<?php
  define('HOST','127.0.0.1:3307');
  define('USER','root');
  define('PASS','');
  define('DB','androiddb');

  $con = mysqli_connect(HOST,USER,PASS,DB) or die('unable to connect');

  $twd= $_GET['id'];

 $sql = "select timeIn , timeOut FROM work_details WHERE twd = '".$twd."'";

  $res = mysqli_query($con,$sql);

  $result=array();


  while($row=mysqli_fetch_array($res)){
      array_push($result,array('id'=>$row[0],'timeIn'=>$row[1],'timeOut'=>$row[2]));
  }

  echo (json_encode(array("result"=>$result)));

mysqli_close($con);

?>

Error

01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ org.json.JSONException: Value <br of type java.lang.String cannot be converted to JSONObject
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at org.json.JSON.typeMismatch(JSON.java:111)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at org.json.JSONObject.<init>(JSONObject.java:159)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at org.json.JSONObject.<init>(JSONObject.java:172)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails.showHours(Edit_WorkDetails.java:248)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails.access$000(Edit_WorkDetails.java:46)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails$1GetHours.onPostExecute(Edit_WorkDetails.java:232)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at com.example.project.myapplication.GUI.Edit_WorkDetails$1GetHours.onPostExecute(Edit_WorkDetails.java:220)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.AsyncTask.finish(AsyncTask.java:632)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.AsyncTask.access$600(AsyncTask.java:177)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.AsyncTask$InternalHandler.handleMessage(AsyncTask.java:645)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.Handler.dispatchMessage(Handler.java:102)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at android.os.Looper.loop(Looper.java:146)
01-10 19:31:47.355    1298-1298/com.example.project.myapplication W/System.err﹕ at android.app.ActivityThread.main(ActivityThread.java:5602)
01-10 19:31:47.360    1298-1298/com.example.project.myapplication W/System.err﹕ at java.lang.reflect.Method.invokeNative(Native Method)
01-10 19:31:47.360    1298-1298/com.example.project.myapplication W/System.err﹕ at java.lang.reflect.Method.invoke(Method.java:515)
01-10 19:31:47.360    1298-1298/com.example.project.myapplication W/System.err﹕ at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
01-10 19:31:47.360    1298-1298/com.example.project.myapplication W/System.err﹕ at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
01-10 19:31:47.360    1298-1298/com.example.project.myapplication W/System.err﹕ at dalvik.system.NativeStart.main(Native Method)
01-10 19:31:47.380    1298-1298/com.example.project.myapplication D/AbsListView﹕ Get MotionRecognitionManager

Why value get display when I use *, but it gives me error when I specific the column name ?

Is it possible that you are getting timeln as time object and you would need to explicitly convert it to string and then push it to json (common logic I do not know php)??? — elrado, Jan 10 '16 at 14:14
@JohnJoe a lot of people here are willing to help you, and this does look like a good question to me, but an all-caps _tell meh y meh codes not workz_ is not going to get you an answer any time sooner. — Nelewout, Jan 10 '16 at 14:41

score 1 · Accepted Answer · answered Jan 10 '16 at 14:40

when mapping your result you are mapping the column $id which you didn't select in the select statement and probably that breaks at the server side and returns an HTML error message to the client which doesn't parse, fix the line:

array_push($result,array('id'=>$row[0],'timeIn'=>$row[1],'timeOut'=>$row[2]));

to:

array_push($result,array('timeIn'=>$row[0],'timeOut'=>$row[1]));

score 1 · Answer 2 · edited May 23 '17 at 10:28

1

@joe,

Here is the issue:

Your query looks like this:

select timeIn , timeOut FROM work_details ....

You access the rows using index based array:

array('id'=>$row[0],'timeIn'=>$row[1],'timeOut'=>$row[2])

You fetching 3 columns instead of 2 you have selected in your SQL

I suggest you do not use numeric arrays when you fetch, because they rely on the position of the fields in your query. This will cause problems and bug if you ever change the query without paying attention at the fetching. You should at least use the associative arrays.

For example:

array('timeIn'=>$row['timeIn'],'timeOut'=>$row['timeOut'])

Even better You can check how I fetched the array in your previous question.

It saves you from bothering matching the fields

$res = mysqli_query($con,$sql);
$result=array();
while($row=mysqli_fetch_array($res)){
    $result[] = $row;
}
echo (json_encode(array("result"=>$result)));

edited May 23 '17 at 10:28

Community

1
1

answered Jan 10 '16 at 14:41

meda

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@JohnJoe I expanded on my answer, you should adjust your code this way, it will be less error prone, no need to parse the result in the loop – meda Jan 10 '16 at 14:49
Meda can you see this ? http://stackoverflow.com/questions/34707414/how-to-get-min-id-value-and-max-id-value-in-mysql-table – John Joe Jan 11 '16 at 02:39
But on the screenshot they are both 10 for twk – meda Jan 11 '16 at 04:09
ya, that's why I use min(id) and max(id) – John Joe Jan 11 '16 at 04:15
Can you start a new question add the JSON – meda Jan 11 '16 at 04:21
ok,check it out https://stackoverflow.com/questions/34735760/get-min-id-and-max-id-value-in-mysql-php..thanks – John Joe Jan 12 '16 at 04:46

Get java.lang.String cannot be converted to JSONObject when trying to retrieve value from a specific column

2 Answers2