patchca整合Spring MVC生成超炫的验证码

转载： http://lavasoft.blog.51cto.com/62575/1406947
@Controller
public  class  Login2Controller {
    private  static  ConfigurableCaptchaService cs =  new  ConfigurableCaptchaService();
    private  static  Random random =  new  Random();
    static  {
//        cs.setColorFactory(new SingleColorFactory(new Color(25, 60, 170)));
        cs.setColorFactory( new  ColorFactory() {
            @Override
            public  Color getColor( int  x) {
                int [] c =  new  int [ 3 ];
                int  i = random.nextInt(c.length);
                for  ( int  fi =  0 ; fi < c.length; fi++) {
                    if  (fi == i) {
                        c[fi] = random.nextInt( 71 );
                    }  else  {
                        c[fi] = random.nextInt( 256 );
                    }
                }
                return  new  Color(c[ 0 ], c[ 1 ], c[ 2 ]);

            }
        });
        RandomWordFactory wf =  new  RandomWordFactory();
        wf.setCharacters( "23456789abcdefghigkmnpqrstuvwxyzABCDEFGHIGKLMNPQRSTUVWXYZ" );
        wf.setMaxLength( 4 );
        wf.setMinLength( 4 );
        cs.setWordFactory(wf);
    }
    @RequestMapping ( "/pcrimg" )
    public  void  crimg(HttpServletRequest request, HttpServletResponse response)  throws  IOException {
        switch  (random.nextInt( 5 )) {
            case  0 :
                cs.setFilterFactory( new  CurvesRippleFilterFactory(cs.getColorFactory()));
                break ;
            case  1 :
                cs.setFilterFactory( new  MarbleRippleFilterFactory());
                break ;
            case  2 :
                cs.setFilterFactory( new  DoubleRippleFilterFactory());
                break ;

            case  3 :
                cs.setFilterFactory( new  WobbleRippleFilterFactory());
                break ;
            case  4 :
                cs.setFilterFactory( new  DiffuseRippleFilterFactory());
                break ;
        }
        HttpSession session = request.getSession( false );
        if  (session ==  null ) {
            session = request.getSession();
        }
        setResponseHeaders(response);
        String token = EncoderHelper.getChallangeAndWriteImage(cs,  "png" , response.getOutputStream());
        session.setAttribute( "captchaToken" , token);
        System.out.println( "当前的SessionID="  + session.getId() +  "，验证码="  + token);
    }
    protected  void  setResponseHeaders(HttpServletResponse response) {
        response.setContentType( "image/png" );
        response.setHeader( "Cache-Control" ,  "no-cache, no-store" );
        response.setHeader( "Pragma" ,  "no-cache" );

        long  time = System.currentTimeMillis();
        response.setDateHeader( "Last-Modified" , time);
        response.setDateHeader( "Date" , time);
        response.setDateHeader( "Expires" , time);
    }
}