kaptcha 验证码使用

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1，关于

验证码是做互联网必须做的。
目前都是用的第三方库。Kaptcha已经迁移到github项目了。
参考博客：http://www.v5cn.cn/?p=157

2，项目中使用Kaptcha

引入pom

<dependency><groupId>com.github.axet</groupId><artifactId>kaptcha</artifactId><version>0.0.9</version>
</dependency>
<!-- kaptcha依赖-->
<dependency><groupId>com.jhlabs</groupId><artifactId>imaging</artifactId><version>01012005</version>
</dependency>

默认Kaptcha使用的是servlet，找到servlet迁移到 srping mvc。

controller代码：

import com.google.code.kaptcha.Producer;
import com.google.code.kaptcha.util.Config;
import com.octo.captcha.service.CaptchaServiceException;
import com.octo.captcha.service.image.ImageCaptchaService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;import javax.imageio.ImageIO;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Date;
import java.util.Properties;
import com.google.code.kaptcha.Constants;@Controller
@RequestMapping(value = "/demo", method = {RequestMethod.GET})
public class KcaptchaController {public static final String CAPTCHA_IMAGE_FORMAT = "jpeg";//--kapcha验证码。private Properties props = new Properties();private Producer kaptchaProducer = null;private String sessionKeyValue = null;private String sessionKeyDateValue = null;public KcaptchaController() {ImageIO.setUseCache(false);//设置宽和高。this.props.put(Constants.KAPTCHA_IMAGE_WIDTH, "200");this.props.put(Constants.KAPTCHA_IMAGE_HEIGHT, "60");//kaptcha.border：是否显示边框。this.props.put(Constants.KAPTCHA_BORDER, "no");//kaptcha.textproducer.font.color：字体颜色this.props.put(Constants.KAPTCHA_TEXTPRODUCER_FONT_COLOR, "black");//kaptcha.textproducer.char.space：字符间距this.props.put(Constants.KAPTCHA_TEXTPRODUCER_CHAR_SPACE, "5");//设置字体。this.props.put(Constants.KAPTCHA_TEXTPRODUCER_FONT_SIZE, "40");//this.props.put(Constants.KAPTCHA_NOISE_COLOR, "");//更多的属性设置可以在com.google.code.kaptcha.Constants类中找到。Config config1 = new Config(this.props);this.kaptchaProducer = config1.getProducerImpl();this.sessionKeyValue = config1.getSessionKey();this.sessionKeyDateValue = config1.getSessionDate();}@RequestMapping(value = "/kcaptcha.jpg", method = {RequestMethod.GET})@ResponseBodypublic void kaptcha(@RequestParam(value = "code", defaultValue = "0") String code,HttpServletResponse response, HttpServletRequest request,Model view) throws IOException {// flush it in the responseresponse.setHeader("Cache-Control", "no-store");response.setHeader("Pragma", "no-cache");response.setDateHeader("Expires", 0);response.setContentType("image/" + CAPTCHA_IMAGE_FORMAT);String capText = this.kaptchaProducer.createText();BufferedImage bi = this.kaptchaProducer.createImage(capText);ServletOutputStream out = response.getOutputStream();try {request.getSession().setAttribute(this.sessionKeyValue, capText);request.getSession().setAttribute(this.sessionKeyDateValue, new Date());} catch (Exception e) {e.printStackTrace();}ImageIO.write(bi, CAPTCHA_IMAGE_FORMAT, out);}
}