NIO: между Сциллой и Харибдой?

package asyncexample1;

import java.nio.*;
import java.nio.channels.*;
import java.nio.file.*;
import java.util.concurrent.Future;
import static java.nio.file.StandardOpenOption.*;

public class AsyncExample1 {

private static long startSync, stopSync, stopAsync, filePosition;
private static String writePath = «C:\\tmp\\tmp1.txt»;
private static int bufferSize = 1024*1024;

public static void main(String[] args)
{

//---------- Initializing parameters —
ByteBuffer buffer = ByteBuffer.allocate(bufferSize);
filePosition = 0;
startSync = stopSync = stopAsync = 0;

//---------- Initializing buffer —

int n = buffer.limit();
byte[] data = new byte[n];
for ( int i=0; i<n; i++ ) { data[i] = '*'; }
buffer.put(data);
buffer.flip();

//---------- Create file channel — // Note this operation is outside of time measurement interval

Path path = Paths.get(writePath);
try ( AsynchronousFileChannel writeChannel =
AsynchronousFileChannel.open( path, CREATE, WRITE ); )
{

//---------- Send write request, first interval —
startSync = System.nanoTime();
Future operation = writeChannel.write( buffer, filePosition );
stopSync = System.nanoTime();

//---------- Wait for request execution, second interval — while( !operation.isDone() );
stopAsync = System.nanoTime();

//---------- Exception handling —

} catch (Exception e) { System.out.println( «Error: » + e ); }

//---------- Visual timings results —
printInterval( startSync, stopSync, «Send task» );
printInterval( stopSync, stopAsync, «Execute task»);

}

//---------- Helper method for output results to console — // t1 = start interval time moment, nanoseconds
// t2 = end interval time moment, nanoseconds
// s1 = parameter name string for print

private static void printInterval( long t1, long t2, String s1 )
{
double x = t2-t1;
String s2 = «error, »;
if (x<0) { s2 = s2 + «negative time interval»; }
if (x==0) { s2 = s2 + «too small time»; }
if (x>0)
{
x /= 1000000;
s2 = String.format("%.6f ms", x);
}
System.out.println( s1 + " = " + s2 );
}

//---------- End of main class —
}