Android - Getting from a Uri to an Inputstream to a Byte Array

Android - getting from a Uri to an InputStream to a byte array?

is.toString() will give you a String representation of the InputStream instance, not its content.

You need to read() bytes from the InputStream into your array. There's two read methods to do that, read() which reads a single byte at a time, and read(byte[] bytes) which reads bytes from the InputStream into the byte array you pass to it.

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Update: to read the bytes given that an InputStream does not have a length as such, you need to read the bytes until there is nothing left. I suggest creating a method for yourself something like this is a nice simple starting point (this is how I would do it in Java at least).

public byte[] readBytes(InputStream inputStream) throws IOException {
  // this dynamically extends to take the bytes you read
  ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream();

  // this is storage overwritten on each iteration with bytes
  int bufferSize = 1024;
  byte[] buffer = new byte[bufferSize];

  // we need to know how may bytes were read to write them to the byteBuffer
  int len = 0;
  while ((len = inputStream.read(buffer)) != -1) {
    byteBuffer.write(buffer, 0, len);
  }

  // and then we can return your byte array.
  return byteBuffer.toByteArray();
}

Read file to byte array using uri

As pskink said, your main problem is that you are wrapping your InputStream in a Reader. A Reader is meant to decode bytes into characters, which is, by defintion, what you want to avoid. You need to allocate a buffer and use the InputStream's read method to fill it.

Keep in mind that you have to know the amount of incoming bytes or read multiple times while processing the already received data.

Alternatively, you could use the read method to get an int, check whether the stream has ended, then cast that int to a byte and process one by one. But usually, you want to use a buffer, since that's faster.

Convert InputStream to byte array in Java

You can use Apache Commons IO to handle this and similar tasks.

The IOUtils type has a static method to read an InputStream and return a byte[].

InputStream is;
byte[] bytes = IOUtils.toByteArray(is);

Internally this creates a ByteArrayOutputStream and copies the bytes to the output, then calls toByteArray(). It handles large files by copying the bytes in blocks of 4KiB.

Image Uri to bytesarray

From Uri to get byte[] I do the following things,

InputStream iStream =   getContentResolver().openInputStream(uri);
byte[] inputData = getBytes(iStream);

and the getBytes(InputStream) method is:

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();
    }

Getting bytes[] from inputstream in android gives null value

As pskink suggested in a comment, the issue was that the input stream has been read to the EOF by decodeStream, so there is nothing more to read.

To solve the problem, I created a temporary variable for inputstream.

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