验证码工具类ValidationCodeUtils，以及如何使用

验证码工具类ValidationCodeUtils

使用这个工具类需要的jar包：

ValidationCodeUtils如下：

package com.macw.util;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.awt.image.BufferedImageOp;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import org.patchca.background.BackgroundFactory;
import org.patchca.color.ColorFactory;
import org.patchca.color.RandomColorFactory;
import org.patchca.filter.ConfigurableFilterFactory;
import org.patchca.filter.library.AbstractImageOp;
import org.patchca.filter.library.WobbleImageOp;
import org.patchca.font.RandomFontFactory;
import org.patchca.service.Captcha;
import org.patchca.service.ConfigurableCaptchaService;
import org.patchca.text.renderer.BestFitTextRenderer;
import org.patchca.text.renderer.TextRenderer;
import org.patchca.word.RandomWordFactory;

public class ValidationCodeUtils {
  private static ConfigurableCaptchaService configurableCaptchaService = null;
  private static ColorFactory colorFactory = null;
  private static RandomFontFactory fontFactory = null;
  private static RandomWordFactory wordFactory = null;
  private static TextRenderer textRenderer = null;

  /**
   * 自定义验证码图片背景,主要画一些噪点和干扰线
   */
  private static class MyCustomBackgroundFactory implements BackgroundFactory {
    private Random random = new Random();

    public void fillBackground(BufferedImage image) {
      Graphics graphics = image.getGraphics();

      // 验证码图片的宽高
      int imgWidth = image.getWidth();
      int imgHeight = image.getHeight();

      // 填充为白色背景
      graphics.setColor(Color.WHITE);
      graphics.fillRect(0, 0, imgWidth, imgHeight);

      // 画100个噪点(颜色及位置随机)
      for (int i = 0; i < 100; i++) {
        // 随机颜色
        int rInt = random.nextInt(255);
        int gInt = random.nextInt(255);
        int bInt = random.nextInt(255);

        graphics.setColor(new Color(rInt, gInt, bInt));

        // 随机位置
        int xInt = random.nextInt(imgWidth - 3);
        int yInt = random.nextInt(imgHeight - 2);

        // 随机旋转角度
        int sAngleInt = random.nextInt(360);
        int eAngleInt = random.nextInt(360);

        // 随机大小
        int wInt = random.nextInt(6);
        int hInt = random.nextInt(6);

        graphics.fillArc(xInt, yInt, wInt, hInt, sAngleInt, eAngleInt);

        // 画5条干扰线
        if (i % 20 == 0) {
          int xInt2 = random.nextInt(imgWidth);
          int yInt2 = random.nextInt(imgHeight);
          graphics.drawLine(xInt, yInt, xInt2, yInt2);
        }
      }
    }
  }

  static {
    configurableCaptchaService = new ConfigurableCaptchaService();

    // 颜色创建工厂,使用一定范围内的随机色
    colorFactory = new RandomColorFactory();
    configurableCaptchaService.setColorFactory(colorFactory);

    // 随机字体生成器
    fontFactory = new RandomFontFactory();
    fontFactory.setMaxSize(32);
    fontFactory.setMinSize(28);
    configurableCaptchaService.setFontFactory(fontFactory);

    // 随机字符生成器,去除掉容易混淆的字母和数字,如o和0等
    wordFactory = new RandomWordFactory();
    wordFactory.setCharacters("abcdefghkmnpqstwxyz23456789");
    wordFactory.setMaxLength(5);
    wordFactory.setMinLength(4);
    configurableCaptchaService.setWordFactory(wordFactory);

    // 自定义验证码图片背景
    MyCustomBackgroundFactory backgroundFactory = new MyCustomBackgroundFactory();
    configurableCaptchaService.setBackgroundFactory(backgroundFactory);

    // 图片滤镜设置
    ConfigurableFilterFactory filterFactory = new ConfigurableFilterFactory();

    List<BufferedImageOp> filters = new ArrayList<BufferedImageOp>();
    WobbleImageOp wobbleImageOp = new WobbleImageOp();
    wobbleImageOp.setEdgeMode(AbstractImageOp.EDGE_MIRROR);
    wobbleImageOp.setxAmplitude(2.0);
    wobbleImageOp.setyAmplitude(1.0);
    filters.add(wobbleImageOp);
    filterFactory.setFilters(filters);

    configurableCaptchaService.setFilterFactory(filterFactory);

    // 文字渲染器设置
    textRenderer = new BestFitTextRenderer();
    textRenderer.setBottomMargin(3);
    textRenderer.setTopMargin(3);
    configurableCaptchaService.setTextRenderer(textRenderer);

    // 验证码图片的大小
    configurableCaptchaService.setWidth(82);
    configurableCaptchaService.setHeight(32);
  }

  public static Captcha getCaptcha() {
    return configurableCaptchaService.getCaptcha();
  }

  public static void main(String[] args) {
    Captcha c = getCaptcha();
    System.out.println(c.getChallenge());
  }
}

验证码的使用：

使用strurs2直接访问这个action就可以了

/**
   * 请求验证码
   * @return
   */
  public String ValidationCode() {
    // 调用工具方法获取验证码
    Captcha c = ValidationCodeUtils.getCaptcha();
    String validationCode = c.getChallenge();
    System.out.println("validationCode = " + validationCode);
    setSessionAttribute("validationCode", validationCode);
    // BuffedImage类型对象代表一个图片
    BufferedImage bi = c.getImage();
    // 设置响应类型
    HttpServletResponse response = ServletActionContext.getResponse();
    response.setContentType("image/png");
    response.setHeader("cache", "no-cache");
    // 将图片通过输出流，响应回浏览器
    OutputStream out;
    try {
      out = response.getOutputStream();
      // 将图片bi以png格式使用out流输出
      ImageIO.write(bi, "png", out);
    } catch (IOException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
    return null;
  }