code: private static void processToken( String token, Stack<String> stack, Properties props )
      {
          if( "}".equals( token ) )
          {
              String name = stack.pop();
              String open = stack.pop();
              if( "${".equals( open ) )
              {
                  startProperty( name, props, stack );
              }
              else
              {
                  push( stack, "${" + name + "}" );
              }
          }
          else
          {
              if( "$".equals( token ) )
              {
                  stack.push( "$" );
              }
              else
              {
                  push( stack, token );
              }
          }
      }
docs: Process one token.
  
  @param token The token to process.
  @param stack The parser Stack.
  @param props The Properties to replace.