Problem With Java

[Kusagra]

I am not a good programmer in java but can anyone of you provide some examples regarding lexical analysis in java and syntactical analysis in java

[opaper]

Color getColor(String name) {
    String data;
      StringTokenizer st;
      int red, green, blue;
    
     data = getParameter(name);
       if (data == null)
         return null;
          
      st = new StringTokenizer(data, ",");
       try {
        red = Integer.parseInt(st.nextToken());
           green = Integer.parseInt(st.nextToken());
           blue = Integer.parseInt(st.nextToken());
      } catch (Exception e) {
         return null; // (ERROR STATE) could not parse it
       }
       return new Color(red, green, blue); // (END STATE) done.
   }

[MindSpace]

while (true) {
           Expression res;
        int c = StreamTokenizer.TT_EOL;
            String varName = null;

         System.out.println("Enter an expression...");
            try {
             while (true) {
                 c = st.nextToken();
                 if (c == StreamTokenizer.TT_EOF) {
                      System.exit(1);
                 } else if (c == StreamTokenizer.TT_EOL) {
                       continue;
                 } else if (c == StreamTokenizer.TT_WORD) {
                 if (st.sval.compareTo("dump") == 0) {
                          dumpVariables(variables);
                     continue;
                      } else if (st.sval.compareTo("clear") == 0) {
                         variables = new Hashtable();
                          continue;
                     } else if (st.sval.compareTo("quit") == 0) {
                       System.exit(0);
                      } else if (st.sval.compareTo("exit") == 0) {
                          System.exit(0);
                     } else if (st.sval.compareTo("help") == 0) {
                            help();
                         continue;
                     }
                      varName = st.sval;
                    c = st.nextToken();
             }
                  break;
            }
            if (c != '=') {
                   throw new SyntaxError("missing initial '=' sign.");
        }