public static void main(String[] arguments) {
try {
// read byte data into a byte buffer
String data = "friends.dat";
FileInputStream inData = new FileInputStream(data);
FileChannel inChannel = inData.getChannel();
long inSize = inChannel.size();
ByteBuffer source = ByteBuffer.allocate((int) inSize);
inChannel.read(source, 0);
source.position(0);
System.out.println("Original byte data:");
for (int i = 0; source.remaining() > 0; i++) {
System.out.print(source.get() + " ");
}
// convert byte data into character data
source.position(0);
Charset ascii = Charset.forName("US-ASCII");
CharsetDecoder toAscii = ascii.newDecoder();
CharBuffer destination = toAscii.decode(source);
destination.position(0);
System.out.println("\n\nNew character data:");
for (int i = 0; destination.remaining() > 0; i++) {
System.out.print(destination.get());
}
System.out.println();
} catch (FileNotFoundException fne) {
System.out.println(fne.getMessage());
} catch (IOException ioe) {
System.out.println(ioe.getMessage());
}
}
public static void main(String args[]) throws Exception {
String inputFile = "samplein.txt";
String outputFile = "sampleout.txt";
RandomAccessFile inf = new RandomAccessFile(inputFile, "r");
RandomAccessFile outf = new RandomAccessFile(outputFile, "rw");
long inputLength = new File(inputFile).length();
FileChannel inc = inf.getChannel();
FileChannel outc = outf.getChannel();
MappedByteBuffer inputData = inc.map(FileChannel.MapMode.READ_ONLY, 0, inputLength);
Charset latin1 = Charset.forName("ISO-8859-1");
CharsetDecoder decoder = latin1.newDecoder();
CharsetEncoder encoder = latin1.newEncoder();
CharBuffer cb = decoder.decode(inputData);
// Process char data here
ByteBuffer outputData = encoder.encode(cb);
outc.write(outputData);
inf.close();
outf.close();
}
/**
* Decode file charset.
*
* @param f File to process.
* @return File charset.
* @throws IOException in case of error.
*/
public static Charset decode(File f) throws IOException {
SortedMap<String, Charset> charsets = Charset.availableCharsets();
String[] firstCharsets = {
Charset.defaultCharset().name(), "US-ASCII", "UTF-8", "UTF-16BE", "UTF-16LE"
};
Collection<Charset> orderedCharsets = U.newLinkedHashSet(charsets.size());
for (String c : firstCharsets)
if (charsets.containsKey(c)) orderedCharsets.add(charsets.get(c));
orderedCharsets.addAll(charsets.values());
try (RandomAccessFile raf = new RandomAccessFile(f, "r")) {
FileChannel ch = raf.getChannel();
ByteBuffer buf = ByteBuffer.allocate(4096);
ch.read(buf);
buf.flip();
for (Charset charset : orderedCharsets) {
CharsetDecoder decoder = charset.newDecoder();
decoder.reset();
try {
decoder.decode(buf);
return charset;
} catch (CharacterCodingException ignored) {
}
}
}
return Charset.defaultCharset();
}