How to convert an Image to base64 string in java?

Question

It may be a duplicate but i am facing some problem to convert the image into Base64 for sending it for Http Post. I have tried this code but it gave me wrong encoded string.

 public static void main(String[] args) {

           File f =  new File("C:/Users/SETU BASAK/Desktop/a.jpg");
             String encodstring = encodeFileToBase64Binary(f);
             System.out.println(encodstring);
       }

       private static String encodeFileToBase64Binary(File file){
            String encodedfile = null;
            try {
                FileInputStream fileInputStreamReader = new FileInputStream(file);
                byte[] bytes = new byte[(int)file.length()];
                fileInputStreamReader.read(bytes);
                encodedfile = Base64.encodeBase64(bytes).toString();
            } catch (FileNotFoundException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            return encodedfile;
        }

Output: [B@677327b6

But i converted this same image into Base64 in many online encoders and they all gave the correct big Base64 string.

Edit: How is it a duplicate?? The link which is duplicate of mine doesn't give me solution of converting the string what i wanted.

What am i missing here??

Solution 1

The problem is that you are returning the toString() of the call to Base64.encodeBase64(bytes) which returns a byte array. So what you get in the end is the default string representation of a byte array, which corresponds to the output you get.

Instead, you should do:

encodedfile = new String(Base64.encodeBase64(bytes), "UTF-8");

Solution 2

I think you might want:

String encodedFile = Base64.getEncoder().encodeToString(bytes);

Solution 3

this did it for me. you can vary the options for the output format to Base64.Default whatsoever.

// encode base64 from image
ByteArrayOutputStream baos = new ByteArrayOutputStream();
imageBitmap.compress(Bitmap.CompressFormat.PNG, 100, baos);
byte[] b = baos.toByteArray();
encodedString = Base64.encodeToString(b, Base64.URL_SAFE | Base64.NO_WRAP);