I have a method that does some things that I would like to know what it is ... just explain me out loud please?
private static byte[] readFully(InputStream in) throws IOException {
ByteArrayOutputStream out = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
for (int count; (count = in.read(buffer)) != -1; ) {
out.write(buffer, 0, count);
}
return out.toByteArray();
}
The method in question is reading the entire contents of an input stream (eg, from a file, network port, etc.) to an array of bytes in memory.
The ByteArrayOutputStream is an output that keeps everything you write ( write ) in memory.
The code is basic by reading the content of InputStream in blocks of up to 1KiB (1024 bytes) and writing it in ByteArrayOutputStream . This is a very manual way of buffering the operation.
Finely the line out.toByteArray() returns everything written in ByteArrayOutputStream as a byte[] .
See that there are several libraries and alternate implementations to solve this problem.
InputStream.readAllBytes() for that purpose.