New Charset Encoder/Decoder for Microsoft telnet

Question

Hello,
I have a problem for writing a server which is accessible by microsoft windows telnet.
I have managed to find out these relationships:
          switch ((int) c) {
               case -27: c = '�'; break;
               case -28: c = '�'; break;
               case -102: c = '�'; break;
               case -103: c = '�'; break;
               case -108: c = '�'; break;
               case -114: c = '�'; break;
               case -124: c = '�'; break;
               case -127: c = '�'; break;
So how could i write an encoder/decoder which could map these charcters specially and others as norma ISO-8859-1.
I switched them after encoding/decoding but then i got problem, that
i got two characters(in telnet window). First was some wierd symbol and second the right character.
Any help lplease?

Answer 1

Okay, got working the charset include and everything is okay.
Now i need to look after charcodes below 0. I though that it would be useful to create new charset for this purpose which adds little extra functionality to IBM850. When running this code it says that IBM850 charset not found when initilizating X-MICRO charset. But it is accessible in main program. Any ideas what is wrong?... Please help me, this damn internationallization has driven me mad.
package ee.feelfree.charset;
import java.nio.charset.Charset;
import java.nio.charset.spi.CharsetProvider;
import java.util.HashSet;
import java.util.Iterator;
public class MicrosoftCharsetProvider extends CharsetProvider {
     private static final String CHARSET_NAME = "X-MICRO";
     private Charset micro = null;
     public MicrosoftCharsetProvider()
     this.micro = new MicrosoftCharset (CHARSET_NAME, new String [0]);
     public Iterator charsets() {
          HashSet set = new HashSet (1);
          set.add (micro);
          return (set.iterator());
     public Charset charsetForName (String charsetName) {
          if (charsetName.equalsIgnoreCase (CHARSET_NAME)) {
               return (micro);
               return (null);
package ee.feelfree.charset;
import java.nio.CharBuffer;
import java.nio.charset.*;
import java.nio.ByteBuffer;
public class MicrosoftCharset extends Charset {
     private static final String BASE_CHARSET_NAME = "IBM850";
     Charset baseCharset;
     protected MicrosoftCharset(String canonical,String [] aliases) {
          super (canonical, aliases);
          baseCharset = Charset.forName(BASE_CHARSET_NAME);
     public CharsetEncoder newEncoder() {
          return new MicrosoftEncoder(this,baseCharset.newEncoder());
     public CharsetDecoder newDecoder() {
          return new MicrosoftDecoder(this,baseCharset.newDecoder());
     public boolean contains (Charset cs) {
          return false;
     private class MicrosoftEncoder extends CharsetEncoder {
          private CharsetEncoder baseEncoder;
          MicrosoftEncoder(Charset cs,CharsetEncoder baseEncoder) {
               super(cs, baseEncoder.averageBytesPerChar(),
                         baseEncoder.maxBytesPerChar());
               this.baseEncoder = baseEncoder;
          protected CoderResult encodeLoop (CharBuffer cb, ByteBuffer bb)
               CharBuffer tmpcb = CharBuffer.allocate (cb.remaining());
               while (cb.hasRemaining()) {
               tmpcb.put (cb.get());
               tmpcb.rewind();
               baseEncoder.reset();
               CoderResult cr = baseEncoder.encode (tmpcb, bb, true);
               cb.position (cb.position() - tmpcb.remaining());
               return (cr);
     private class MicrosoftDecoder extends CharsetDecoder
     private CharsetDecoder baseDecoder;
     private boolean microClient = false;
          MicrosoftDecoder (Charset cs, CharsetDecoder baseDecoder)
               super (cs, baseDecoder.averageCharsPerByte(),
               baseDecoder.maxCharsPerByte());
               this.baseDecoder = baseDecoder;
          protected CoderResult decodeLoop (ByteBuffer bb, CharBuffer cb)
               baseDecoder.reset();
               CoderResult result = baseDecoder.decode (bb, cb, true);
               myDecode (cb);
               return (result);
          public boolean getClient() {
               return microClient;
          private void myDecode(CharBuffer cb) {
               microClient = false;
               for (int pos = cb.position(); pos < cb.limit(); pos++) {
                    int c = (int) cb.get (pos);
                    if (c<0) microClient=true;
}