java practical verification code implementation code

This article for you to share java practical verification code implementation code, for your reference, the specific content is as follows

1, ValidCode          

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(" The current SessionID=" + session.getId() + " The verification code = ," + 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 {
 
  }
 
 
}

2.XML code

<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>

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