Converting File into String then into Base64 Fromate With Android Studio

Question

I want to pick a file from an android device, convert that file into string format, convert that string to BASE64 encoding, then pass that encoded string to the server via an API.

I debugged my project and it goes up to this line:

  FileInputStream fis = new FileInputStream(new File(path));

It does not go further.

Can someone please tell me where I am doing wrong?

Thanks in advance.

Here is my code:

      package com.example.deepb.testingencodingapp;

      import android.content.Intent;
      import android.net.Uri;
      import android.support.v7.app.AppCompatActivity;
      import android.os.Bundle;
      import android.util.Log;
      import android.view.View;
      import android.widget.Button;
      import android.widget.EditText;
      import android.widget.TextView;
      import android.util.Base64;
      import java.io.BufferedReader;
      import java.io.ByteArrayOutputStream;
      import java.io.File;
      import java.io.FileInputStream;
      import java.io.FileNotFoundException;
      import java.io.IOException;
      import java.io.InputStreamReader;


  public class MainActivity extends AppCompatActivity {

EditText fatchValue;
TextView displayValue,Fpath;
Button GetValue,SelectFile;
String  ret,uriString,finalString;
File myFile;
String line = null;
private static final int PICKFILE_RESULT_CODE = 1;
public static final int RESULT_OK = -1;
Uri uri;
byte[] fileBytes;



@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    fatchValue = findViewById(R.id.enterText);
    displayValue = findViewById(R.id.displayText);
    Fpath = findViewById(R.id.pathText);
    GetValue = findViewById(R.id.btn_go);
    SelectFile = findViewById(R.id.uploadFile);



    GetValue.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            String GotValue = fatchValue.getText().toString();
            byte[] encodeValue = Base64.encode(finalString.getBytes(), Base64.DEFAULT);
            String ansValue = encodeValue.toString();
            //displayValue.setText(ansValue);
            displayValue.setText(finalString);
            Log.d(finalString,"this is the String " + finalString);

        }
    });

    SelectFile.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent getFile = new Intent(Intent.ACTION_GET_CONTENT);
            getFile.setType("*/*");
            startActivityForResult(getFile,PICKFILE_RESULT_CODE);
        }
    });
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == RESULT_OK) {
        uri = data.getData();
        uriString = uri.toString();
        myFile = new File(uriString);
        ret = myFile.getAbsolutePath();
        Fpath.setText(ret);

        try {
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            String path = ret;
            FileInputStream fis = new FileInputStream(new File(path));

            byte[] buf = new byte[1024];
            int n;
            while (-1 != (n = fis.read(buf)))
                baos.write(buf, 0, n);

            fileBytes = baos.toByteArray();
            //Log.i("ByteArray" + path + ">><<" + ret, "----" + fileBytes.toString());
            finalString = fileBytes.toString();
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
     }

not a single error..it get perfectly execute upto this line `FileInputStream fis = new FileInputStream(new File(path));` then I get "fileBytes" = null. So "finalString=null".. This is What i get in Logcat.. /com.example.deepb.testingencodingapp E/Activity: onResume-Exception-e:Attempt to invoke interface method 'void android.app.applock.ILavaAppLockService.startLockMonitor(java.lang.String, java.lang.String)' on a null object reference /com.example.deepb.testingencodingapp E/SpannableStringBuilder: SPAN_EXCLUSIVE_EXCLUSIVE spans cannot have a zero length — deep bhatt, Jul 26 '18 at 14:12
hey @GinoMempin..May be problem is that file can not get read by `FileInputStream`..that's what I think.. can you please provide me any solution for this? What I am doing wrong or where I am going wrong? — deep bhatt, Jul 26 '18 at 21:03
Hmm. My initial understanding when you said _"it goes up to this line"_ and _"It does not go further."_ was that it _stops running_ or throws an exception at `new FileInputStream(new File(path));`. So the _actual_ problem is in reading the file. If "fileBytes = null" as you said, then you should be getting a `NullPointerException` at `finalString = fileBytes.toString();`. Is it really null or empty/zero? BTW, that logcat error you shared isn't related to the problem (it's a common error when using EditText). — Gino Mempin, Jul 26 '18 at 23:39
Since what you really need are the file contents as `String`, try using `BufferedReader` to read it as `String` instead of bytes. Something like https://stackoverflow.com/questions/12910503/read-file-as-string/13357785#13357785. — Gino Mempin, Jul 26 '18 at 23:44
Hey @GinoMempin Thank you for your answer. code goes upto that line then no result no error. And last fileBytes was null so finalString was null(checked in log). And yes May be I was not using bufferedReader and some RUNTIME permissions. Really Appreciate for your time. Thanks Again. — deep bhatt, Jul 27 '18 at 15:22

Dishant Patel · Accepted Answer · 2018-07-28T07:22:59.850

public class DeppDemo extends AppCompatActivity {

EditText fatchValue;
TextView displayValue, Fpath;
Button GetValue, SelectFile;
String ret, uriString, finalString;
File myFile;
String line = null;
private static final int PICKFILE_RESULT_CODE = 1;
public static final int RESULT_OK = -1;
Uri uri;
byte[] fileBytes;
StringBuilder total = new StringBuilder();


String[] permissions = new String[]{
        android.Manifest.permission.READ_EXTERNAL_STORAGE,
        android.Manifest.permission.WRITE_EXTERNAL_STORAGE,
};

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    checkPermissions();

    displayValue = findViewById(R.id.displayText);
    Fpath = findViewById(R.id.pathText);
    GetValue = findViewById(R.id.btn_go);
    SelectFile = findViewById(R.id.uploadFile);


    GetValue.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {

            String s = "Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.";
            //String GotValue = fatchValue.getText().toString();
            // byte[] encodeValue = Base64.encode(finalString.getBytes(), Base64.DEFAULT);
            // byte[] encodeValue = Base64.encode(fileBytes, Base64.DEFAULT);
            byte[] encodeValue = Base64.encode(total.toString().getBytes(), Base64.DEFAULT);
            //byte[] encodeValue = Base64.encode(s.getBytes(), Base64.DEFAULT);
            String ansValue = encodeValue.toString();
            try {
                String text = new String(encodeValue, "UTF-8");
                displayValue.setText(text);

            } catch (UnsupportedEncodingException e) {
                e.printStackTrace();
            }

            //displayValue.setText(ansValue);
            Log.d(finalString, "this is the String " + finalString);

        }
    });

    SelectFile.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Intent getFile = new Intent(Intent.ACTION_GET_CONTENT);
            getFile.setType("*/*");
            startActivityForResult(getFile, PICKFILE_RESULT_CODE);
        }
    });
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if (resultCode == RESULT_OK) {
        uri = data.getData();
        uriString = uri.toString();


        try {
            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            String path = ret;
            InputStream in = getContentResolver().openInputStream(uri);
            InputStreamReader inputStreamReader = new InputStreamReader(in);

            BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

            String line;
            while ((line = bufferedReader.readLine()) != null) {
                total.append(line).append('\n');
            }


        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
            Log.d("error", "onActivityResult: " + e.toString());
        }
    }
}

private boolean checkPermissions() {


    int result;
    List<String> listPermissionsNeeded = new ArrayList<>();
    for (String p : permissions) {
        result = ContextCompat.checkSelfPermission(this, p);
        if (result != PackageManager.PERMISSION_GRANTED) {
            listPermissionsNeeded.add(p);
        }
    }
    if (!listPermissionsNeeded.isEmpty()) {

        ActivityCompat.requestPermissions(this, listPermissionsNeeded.toArray(new String[listPermissionsNeeded.size()]), 100);
        return false;

    }
    return true;

}

}

its not covert proper base64 so try this one

    public class DeppDemo extends AppCompatActivity {

    EditText fatchValue;
    TextView displayValue, Fpath;
    Button GetValue, SelectFile;
    String ret, uriString, finalString;
    File myFile;
    String line = null;
    private static final int PICKFILE_RESULT_CODE = 1;
    public static final int RESULT_OK = -1;
    Uri uri;
    byte[] fileBytes;
    StringBuilder total = new StringBuilder();
    byte[] bytes;
    ByteArrayOutputStream output;




    String[] permissions = new String[]{
            android.Manifest.permission.READ_EXTERNAL_STORAGE,
            android.Manifest.permission.WRITE_EXTERNAL_STORAGE,
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        checkPermissions();

        displayValue = findViewById(R.id.displayText);
        Fpath = findViewById(R.id.pathText);
        GetValue = findViewById(R.id.btn_go);
        SelectFile = findViewById(R.id.uploadFile);


        GetValue.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {



//                String s = "Man is distinguished, not only by his reason, but by this singular passion from other animals, which is a lust of the mind, that by a perseverance of delight in the continued and indefatigable generation of knowledge, exceeds the short vehemence of any carnal pleasure.";
//                //String GotValue = fatchValue.getText().toString();
//                // byte[] encodeValue = Base64.encode(finalString.getBytes(), Base64.DEFAULT);
//                // byte[] encodeValue = Base64.encode(fileBytes, Base64.DEFAULT);
//                Log.d("image string", "onClick: "+total);
//                byte[] encodeValue = new byte[0];
//                try {
//                    encodeValue = Base64.encode(total.toString().getBytes("UTF-8"), Base64.DEFAULT);
//                } catch (UnsupportedEncodingException e) {
//                    e.printStackTrace();
//                }
//                //byte[] encodeValue = Base64.encode(s.getBytes(), Base64.DEFAULT);
//                String ansValue = encodeValue.toString();
//                try {
//                    String text = new String(encodeValue, "UTF-8");
//                    //displayValue.setText(text);
//                    Log.d("Base64", "onClick: "+text);
//                    Log.d("Base64 byte", "onClick: "+encodeValue);
//                    //String encodedString = Base64.encodeToString(bytes, Base64.DEFAULT);
//                    String encodedString = Base64.encodeToString(output.toByteArray(), Base64.DEFAULT);
//                    Log.d("Base64 ==2", "onClick: "+encodedString);
//
//
//                } catch (UnsupportedEncodingException e) {
//                    e.printStackTrace();
//                }
//
//                //displayValue.setText(ansValue);
//                Log.d(finalString, "this is the String " + finalString);

            }
        });

        SelectFile.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent getFile = new Intent(Intent.ACTION_GET_CONTENT);
                getFile.setType("*/*");
                startActivityForResult(getFile, PICKFILE_RESULT_CODE);
            }
        });
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (resultCode == RESULT_OK) {
            uri = data.getData();
            uriString = uri.toString();
            Log.d("data", "onActivityResult: uri"+uriString);
            //            myFile = new File(uriString);
            //            ret = myFile.getAbsolutePath();
            //Fpath.setText(ret);

            try {
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                String path = ret;
                InputStream in = getContentResolver().openInputStream(uri);

                bytes=getBytes(in);
                Log.d("data", "onActivityResult: bytes size="+bytes.length);

                Log.d("data", "onActivityResult: Base64string="+Base64.encodeToString(bytes,Base64.DEFAULT));


//                InputStreamReader inputStreamReader = new InputStreamReader(in);
//                BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
//                String line;
//                while ((line = bufferedReader.readLine()) != null) {
//                    total.append(line);
//                }
//                
//                byte[] buffer = new byte[8192];
//                int bytesRead;
//                output = new ByteArrayOutputStream();
//                int count=0;
//                try {
//                    while ((bytesRead = in.read(buffer)) != -1) {
//                        output.write(buffer, 0, bytesRead);
//                        count++;
//                    }
//                } catch (IOException e) {
//                    Log.d("error byte", "onActivityResult: " + e.toString());
//                    e.printStackTrace();
//                }
//                bytes = output.toByteArray();
//
//                Toast.makeText(this, "Done", Toast.LENGTH_SHORT).show();
                // FileInputStream fis = new FileInputStream(new File(uri.getPath()));

            //                byte[] buf = new byte[1024];
//                int n;
//                while (-1 != (n = in.read(buf))) {
//                    baos.write(buf, 0, n);
//                }
//                fileBytes = baos.toByteArray();
//                //Log.i("ByteArray" + path + ">><<" + ret, "----" + fileBytes.toString());
//                finalString = fileBytes.toString();


            } catch (Exception e) {
                // TODO: handle exception
                e.printStackTrace();
                Log.d("error", "onActivityResult: " + e.toString());
            }
        }
    }


    public byte[] getBytes(InputStream inputStream) throws IOException {
        ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream();
        int bufferSize = 1024;
        byte[] buffer = new byte[bufferSize];

        int len = 0;
        while ((len = inputStream.read(buffer)) != -1) {
            byteBuffer.write(buffer, 0, len);
        }
        return byteBuffer.toByteArray();
    }

    private boolean checkPermissions() {


        int result;
        List<String> listPermissionsNeeded = new ArrayList<>();
        for (String p : permissions) {
            result = ContextCompat.checkSelfPermission(this, p);
            if (result != PackageManager.PERMISSION_GRANTED) {
                listPermissionsNeeded.add(p);
            }
        }
        if (!listPermissionsNeeded.isEmpty()) {

            ActivityCompat.requestPermissions(this, listPermissionsNeeded.toArray(new String[listPermissionsNeeded.size()]), 100);
            return false;

        }
        return true;

    }

}

Thank you Sooo much..It is working for me. With all type of (Small)file. — deep bhatt, Jul 30 '18 at 16:09

Converting File into String then into Base64 Fromate With Android Studio

1 Answers1

Linked