import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.nio.channels.FileChannel;
public class MainClass {
public static void main(String[] args) throws Exception {
File fromFile = new File("fromFile.txt");
File toFile = new File("toFile.txt");
FileInputStream inFile = new FileInputStream(fromFile);
FileOutputStream outFile = new FileOutputStream(toFile);
FileChannel inChannel = inFile.getChannel();
FileChannel outChannel = outFile.getChannel();
int bytesWritten = 0;
long byteCount = inChannel.size();
while (bytesWritten < byteCount) {
bytesWritten += inChannel.transferTo(bytesWritten, byteCount - bytesWritten, outChannel);
}
inFile.close();
outFile.close();
}
}