InputStream will not reset to beginning

Question

InputStream data = realResponse.getEntity().getContent();
byte[] preview = new byte[100];
data.read(preview, 0, 100);

// Now I want to refer to the

Answer 1

If the InputStream supports mark (you can check with the markSupported() method), then the following should work:

InputStream data = realResponse.getEntity().getContent();
byte[] preview = new byte[100];
data.mark(100);
data.read(preview, 0, 100);
data.reset();

However, be aware that data.read(preview, 0, 100) is not guaranteed to read 100 bytes in one go, it may read less.