class CommandParser{  public static final int CMD_AUTHENTICATE = 1;  public static final int CMD_USER_JOINED = 2;  public static final int CMD_USER_LEFT = 3;  public static final int CMD_MESSAGE_RECEIVED = 4;  public static final int CMD_ALL_MESSAGE_RECEIVED = 5;  public static final int CMD_SERVER_SHUTDOWN = 6;   private boolean bFromServer;  private boolean bValid;  private int iCommand;  private String sUsername;  private String sData;  public void clientProtocol(boolean isClient)  {    bFromServer = isClient;   }  public void parseData(String sData)  {    boolean bGetUser, bGetData;    bGetUser = false;    bGetData = false;        // Clear the variables    bValid = false;    iCommand = 0;    sUsername = "";    this.sData = "";        // First get the valid code (+ or -)    bValid = sData.substring(0,1).equalsIgnoreCase("+");        // Now get the code    iCommand = Integer.parseInt(sData.substring(1,3));    // Test the command and see what data to extract    if(!bFromServer && iCommand == CMD_AUTHENTICATE)      bGetUser = true;    if(bFromServer && !bValid && iCommand == CMD_AUTHENTICATE)      bGetData = true;    if(bFromServer && bValid && iCommand == CMD_USER_JOINED)      bGetUser = true;    if(bFromServer && bValid && iCommand == CMD_USER_LEFT)      bGetUser = true;    if(iCommand == CMD_MESSAGE_RECEIVED ||      (iCommand == CMD_ALL_MESSAGE_RECEIVED && bFromServer))    {      bGetUser = true;      bGetData = true;    }    if(iCommand == CMD_ALL_MESSAGE_RECEIVED && ! bFromServer)      bGetData = true;    // If we only want the user then extract the user details    if(bGetUser && !bGetData)    {      sUsername = sData.substring(3, sData.length());    }    // If we only want the data then extract the data    if(!bGetUser && bGetData)    {      this.sData = sData.substring(3, sData.length());    }       // If we want both the username and data then get them both    if(bGetUser && bGetData)    {      int iPos;      iPos = sData.indexOf("~");      if(iPos > 0)      {        sUsername = sData.substring(3, iPos);        this.sData = sData.substring(iPos + 1, sData.length());      }    }  }  public boolean isValid()  {    return bValid;  }  public int getCommand()  {    return iCommand;  }  public String getUser()  {    return sUsername;  }  public String getData()  {    return sData;  }}