How to use a SubString method with string array in java

Question

class DownloadFileAsync extends AsyncTask<String, String, String> {

        @Override
        protected String doInBackground(String... params) {
            // TODO Auto-generated method stub

            int count;
            String destination = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/" ;


            String[] fileName = params;
            String a = fileName.toString();
            String b = a.substring(20,25);
            destination+=b;


            try {

                URL url = new URL(params[0]);
                URLConnection conexion = url.openConnection();
                conexion.connect();

                int lengthofFile = conexion.getContentLength();
                Log.d("ANDRO_ASYNC", "Length of file: " + lengthofFile);

                InputStream input = new BufferedInputStream(url.openStream());
                OutputStream output = new FileOutputStream(destination);

                byte data[] = new byte[1024];

                long total = 0;

                while ((count = input.read(data)) != -1) {
                    total += count;
                    publishProgress("" + (int) ((total * 100) / lengthofFile));
                    output.write(data, 0, count);
                }

                output.flush();
                output.close();
                input.close();
            } catch (Exception e) {
                // TODO: handle exception
            }
            return null;
        }

my param variable will contain the url link which is "http://ledeveloper.in/ep123BCA.pdf" and i want to cut that url..the desire string which i want "ep123BCA.pdf".

But when i run this code the substring Method will always give me a different sub string how to solve that problem.

please help and thanx in advance.

use split method `String[] parts= url.split("/");` it will split the url into 3 or 4 parts, last one is the file name , this is a one way — Mohammed Elrashied, Jan 25 '17 at 11:29
not working for me that give me a same garbage name of the downloaded file. :( — Saurabh Saini, Jan 25 '17 at 12:30

diiN__________ · Answer 1 · 2017-01-25T11:33:26.230

2

Use lastIndexOf to get the file name from the URL:

String b = a.substring(a.lastIndexOf('/') + 1);

edited Jan 25 '17 at 11:33

answered Jan 25 '17 at 11:27

diiN__________

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score 0 · Answer 2 · answered Jan 25 '17 at 11:29

0

You can use this.

fileName=a.substring(a.lastIndexOf("/")+1);

answered Jan 25 '17 at 11:29

Rahul Giradkar

1,818
1
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score 0 · Answer 3 · answered Jan 25 '17 at 11:31

0

Another solution is (if the first part of the url never change)

a.substring(22)

This should split the string this way:

the part cut out = http://ledeveloper.in/
a = ep123BCA.pdf

answered Jan 25 '17 at 11:31

jonaslagoni

663
7
23

It is a solution, but it's not flexible enough. – Todor Kostov Jan 25 '17 at 11:35
That is most certainly correct :) – jonaslagoni Jan 25 '17 at 11:37
giving a garbage name of the file. – Saurabh Saini Jan 25 '17 at 12:31

score 0 · Answer 4 · answered Jan 25 '17 at 11:32

0

String url = "http://ledeveloper.in/ep123BCA.pdf";
         String file = url.substring(url.lastIndexOf('/')+1);

answered Jan 25 '17 at 11:32

Karthik CP

1,150
13
24

score 0 · Answer 5 · edited Jan 25 '17 at 11:46

0

filename = a.substring(a.lastIndexOf("/")+1);

This line replace with your code.

edited Jan 25 '17 at 11:46

Ronak Chaniyara

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answered Jan 25 '17 at 11:35

surilshah08

1
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How to use a SubString method with string array in java

5 Answers5