What does this error in my Logcat mean

Question

I am having problem to understand the error in my Logcat,can you help me please how can i fixed this.

    04-06 08:17:54.738: E/AndroidRuntime(4491): FATAL EXCEPTION: AsyncTask #1
    04-06 08:17:54.738: E/AndroidRuntime(4491): java.lang.RuntimeException: An error   occured while executing doInBackground()
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.os.AsyncTask$3.done(AsyncTask.java:299)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:352)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.util.concurrent.FutureTask.setException(FutureTask.java:219)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.util.concurrent.FutureTask.run(FutureTask.java:239)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:230)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.lang.Thread.run(Thread.java:841)
04-06 08:17:54.738: E/AndroidRuntime(4491): Caused by: java.lang.NullPointerException: println needs a message
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.util.Log.println_native(Native Method)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.util.Log.e(Log.java:231)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at com.example.logintest.adduser$AssCrounTask.doInBackground(adduser.java:118)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at com.example.logintest.adduser$AssCrounTask.doInBackground(adduser.java:1)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.os.AsyncTask$2.call(AsyncTask.java:287)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at java.util.concurrent.FutureTask.run(FutureTask.java:234)
04-06 08:17:54.738: E/AndroidRuntime(4491):     ... 4 more

Answer 1

To report crashs to logcat you should use Log.d/v/etc(TAG, Message, Throwable) not e.printStackTrace().

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Anyway, your code crashs because e.getMessage() could be null and Log don't accept null as message.

So change your line to

Log.e("MY_APP_error!", "Error!", e);

Answer 2

The message you put in Log is null. That is written right here:

Caused by: java.lang.NullPointerException: println needs a message
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.util.Log.println_native(Native Method)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.util.Log.e(Log.java:231)
04-06 08:17:54.738: E/AndroidRuntime(4491):     at com.example.logintest.adduser$AssCrounTask.doInBackground(adduser.java:118)

Check what you are using in Log message.

Answer 3

As your logcat says

04-06 08:17:54.738: E/AndroidRuntime(4491): Caused by: java.lang.NullPointerException: println needs a message
04-06 08:17:54.738: E/AndroidRuntime(4491):     at android.util.Log.println_native(Native Method)

You have a NullPointerException, probably you call Log.e() and pass a null value in a variable.