public static void main(String args[]) {
try {
aServer asr = new aServer();
// file channel.
FileInputStream is = new FileInputStream("");
is.read();
FileChannel cha = is.getChannel();
ByteBuffer bf = ByteBuffer.allocate(1024);
bf.flip();
cha.read(bf);
// Path Paths
Path pth = Paths.get("", "");
// Files some static operation.
Files.newByteChannel(pth);
Files.copy(pth, pth);
// file attribute, other different class for dos and posix system.
BasicFileAttributes bas = Files.readAttributes(pth, BasicFileAttributes.class);
bas.size();
} catch (Exception e) {
System.err.println(e);
}
System.out.println("hello ");
}
public static void main(String[] args) throws IOException {
System.out.println("Input Stream:");
long start = System.currentTimeMillis();
Path filename = Paths.get(args[0]);
long crcValue = checksumInputStream(filename);
long end = System.currentTimeMillis();
System.out.println(Long.toHexString(crcValue));
System.out.println((end - start) + " milliseconds");
System.out.println("Buffered Input Stream:");
start = System.currentTimeMillis();
crcValue = checksumBufferedInputStream(filename);
end = System.currentTimeMillis();
System.out.println(Long.toHexString(crcValue));
System.out.println((end - start) + " milliseconds");
System.out.println("Random Access File:");
start = System.currentTimeMillis();
crcValue = checksumRandomAccessFile(filename);
end = System.currentTimeMillis();
System.out.println(Long.toHexString(crcValue));
System.out.println((end - start) + " milliseconds");
System.out.println("Mapped File:");
start = System.currentTimeMillis();
crcValue = checksumMappedFile(filename);
end = System.currentTimeMillis();
System.out.println(Long.toHexString(crcValue));
System.out.println((end - start) + " milliseconds");
}
public static void main(String args[]) {
int count;
Path filepath = null;
// First, obtain a path to the file.
try {
filepath = Paths.get("test.txt");
} catch (InvalidPathException e) {
System.out.println("Path Error " + e);
return;
}
// Next, obtain a channel to that file within a try-with-resources block.
try (SeekableByteChannel fChan = Files.newByteChannel(filepath)) {
// Allocate a buffer.
ByteBuffer mBuf = ByteBuffer.allocate(128);
do {
// Read a buffer.
count = fChan.read(mBuf);
// Stop when end of file is reached.
if (count != -1) {
// Rewind the buffer so that it can be read.
mBuf.rewind();
// Read bytes from the buffer and show
// them on the screen as characters.
for (int i = 0; i < count; i++) System.out.print((char) mBuf.get());
}
} while (count != -1);
System.out.println();
} catch (IOException e) {
System.out.println("I/O Error " + e);
}
}
