package class9_1_FileChannelAndByteBuffer;

import java.io.*;
import java.nio.ByteBuffer;

/**
 * Like Reader, only using a FileChannel.
 *
 * Now we can read a whole buffer at a time...
 *
 * We still don't handle all the problems that could occur.
 */
public class FileChannelReader {
    public static void main(String[] args) {
        try(FileInputStream is = new FileInputStream("binary.bin")) {
            int firstByteAsInt = is.read();
            ByteBuffer buffer = ByteBuffer.allocate(firstByteAsInt);
            is.getChannel().read(buffer);
            buffer.rewind();
            for(int i = 0; i<firstByteAsInt; i++) {
                System.out.println(i+": "+(int)buffer.get());
            }
            buffer.rewind();
            for(int i = 0; i<firstByteAsInt; i++) {
                System.out.println(i+": "+(int)buffer.get());
            }
        } catch (FileNotFoundException e) {
            System.out.println("The file was not found.");
        } catch (IOException e) {
            System.out.println("An unexpected problem occurred while trying to read the file.");
            throw new RuntimeException(e);
        }
    }
}