Java 生成好看的验证码

http://www.oschina.net/code/snippet_1760858_54871

/Make_img_util
使用 官方jar生成验证图片

      <dependency>
          <groupId>com.github.bingoohuang</groupId>
          <artifactId>patchca</artifactId>
          <version>0.0.1</version>
      </dependency>
 
<servlet>
  <servlet-name>ValidCode</servlet-name>
  <servlet-class>validImg.ValidCode</servlet-class>
</servlet>
<servlet-mapping>
  <servlet-name>ValidCode</servlet-name>
  <url-pattern>/validImg.jpg</url-pattern>
</servlet-mapping>

package validImg;
 
import java.awt.Color;
import java.io.IOException;
import java.util.Random;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import com.github.bingoohuang.patchca.color.ColorFactory;
import com.github.bingoohuang.patchca.custom.ConfigurableCaptchaService;
import com.github.bingoohuang.patchca.filter.predefined.CurvesRippleFilterFactory;
import com.github.bingoohuang.patchca.filter.predefined.DiffuseRippleFilterFactory;
import com.github.bingoohuang.patchca.filter.predefined.DoubleRippleFilterFactory;
import com.github.bingoohuang.patchca.filter.predefined.MarbleRippleFilterFactory;
import com.github.bingoohuang.patchca.filter.predefined.WobbleRippleFilterFactory;
import com.github.bingoohuang.patchca.utils.encoder.EncoderHelper;
import com.github.bingoohuang.patchca.word.RandomWordFactory;
 
public class ValidCode extends HttpServlet {
    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);
    }
 
 
    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, 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("validCode", 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);
    }
 
    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
 
    }
 
 
}