基于jcaptcha1.0的图片验证码实例(忽略大小写)
后台代码
为了控制验证码的样式，并且校验时忽略大小写，需要基于API自定义实现类。（实现方法来源于网络）
事先引入jcaptcha-1.0.jar，下面是自定义的java类文件：
MyGimpy.class
/**
* 自定义验证码实现类，参考Gimpy.class源码，修改后支持“忽略大小写”功能
*/
public class MyGimpy extends ImageCaptcha implements Serializable {
private String response;
MyGimpy(String question, BufferedImage challenge, String response) {
super(question, challenge);
this.response = response;
}
public final Boolean validateResponse(final Object response) {
return (null != response && response instanceof String)
? validateResponse((String) response) : Boolean.FALSE;
}
private final Boolean validateResponse(final String response) {
// 主要改的这里
return new Boolean(response.toLowerCase().equals(this.response.toLowerCase()));
}
}
MyGimpyFactory.class
/**
* 自定义验证码工厂：使用MyGimpy类，支持“忽略大小写”
*/
public class MyGimpyFactory extends ImageCaptchaFactory {
private Random myRandom = new SecureRandom();
private WordToImage wordToImage;
private WordGenerator wordGenerator;
public static final String BUNDLE_QUESTION_KEY = Gimpy.class.getName();
public MyGimpyFactory(WordGenerator generator, WordToImage word2image) {
if (word2image == null) {
throw new CaptchaException("Invalid configuration"
+ " for a GimpyFactory : WordToImage can't be null");
}
if (generator == null) {
throw new CaptchaException("Invalid configuration"
+ " for a GimpyFactory : WordGenerator can't be null");
}
wordToImage = word2image;
wordGenerator = generator;
}
public ImageCaptcha getImageCaptcha() {
return getImageCaptcha(Locale.getDefault());
}
public WordToImage getWordToImage() {
return wordToImage;
}
public WordGenerator getWordGenerator() {
return wordGenerator;
}
public ImageCaptcha getImageCaptcha(Locale locale) {
Integer wordLength = getRandomLength();
String word = getWordGenerator().getWord(wordLength, locale);
BufferedImage image = null;
try {
image = getWordToImage().getImage(word);
} catch (Throwable e) {
throw new CaptchaException(e);
}
// 这里用我们自己写的MyGimpy
ImageCaptcha captcha = new MyGimpy(CaptchaQuestionHelper.getQuestion(
locale, BUNDLE_QUESTION_KEY), image, word);
return captcha;
}
protected Integer getRandomLength() {
Integer wordLength;
int range = getWordToImage().getMaxAcceptedWordLength()
- getWordToImage().getMinAcceptedWordLength();
int randomRange = range != 0 ? myRandom.nextInt(range + 1) : 0;
wordLength = new Integer(randomRange
+ getWordToImage().getMinAcceptedWordLength());
return wordLength;
}
}
GMailEngine.class
/**
* 自定义验证码引擎：仿照JCaptcha2.0编写GMail验证码样式的图片引擎.
* 同时使用自定义的MyGimpyFactory，支持“忽略大小写”
*/
public class GMailEngine extends ListImageCaptchaEngine {
@Override
protected void buildInitialFactories() {
int minWordLength = 4;
int maxWordLength = 5;
int fontSize = 50;
int imageWidth = 250;
int imageHeight = 100;
WordGenerator dictionnaryWords = new ComposeDictionaryWordGenerator(new FileDictionary("toddlist"));
TextPaster randomPaster = new DecoratedRandomTextPaster(minWordLength, maxWordLength,
new RandomListColorGenerator(new Color[]{new Color(23, 170, 27), new Color(220, 34, 11),
new Color(23, 67, 172)}), new TextDecorator[]{}
);
BackgroundGenerator background = new UniColorBackgroundGenerator(imageWidth, imageHeight, new Color(223, 221, 221));
FontGenerator font = new RandomFontGenerator(fontSize, fontSize, new Font[]{
new Font("nyala", Font.BOLD, fontSize), new Font("Bell MT", Font.PLAIN, fontSize),
new Font("Credit valley", Font.BOLD, fontSize)});
ImageDeformation postDef = new ImageDeformationByFilters(new ImageFilter[]{});
ImageDeformation backDef = new ImageDeformationByFilters(new ImageFilter[]{});
ImageDeformation textDef = new ImageDeformationByFilters(new ImageFilter[]{});
WordToImage word2image = new DeformedComposedWordToImage(font, background, randomPaster, backDef, textDef,
postDef);
//这里使用自定义的验证码工厂
addFactory(new MyGimpyFactory(dictionnaryWords, word2image));
}
}
CaptchaServiceSingleton.class
/**
* 保证CaptchaService单例
*/
public class CaptchaServiceSingleton {
private static CaptchaService captchaService=new DefaultManageableImageCaptchaService(new FastHashMapCaptchaStore(),
new GMailEngine(), 180, 100000, 75000);
private CaptchaServiceSingleton(){}
public static BufferedImage generate(String sessionId) throws IOException {
return ((AbstractManageableImageCaptchaService) captchaService).getImageChallengeForID(sessionId);
}
public static boolean validate(String sessionId, String authCode) {
return captchaService.validateResponseForID(sessionId, authCode);
}
}
处理请求
/**
* 验证码控制器 （这里基于spring mvc）
*/
@Controller
public class CaptchaController {
/**生成*/
@RequestMapping("/captcha/generate")
public void generate(HttpServletRequest request,
HttpServletResponse response) throws IOException {
String sessionId = request.getSession().getId();
response.setHeader("Cache-Control", "no-store");
response.setHeader("Pragma", "no-cache");
response.setDateHeader("Expires", 0);
response.setContentType("image/jpeg");
BufferedImage bufferedImage = CaptchaServiceSingleton
.generate(sessionId);
ServletOutputStream out = response.getOutputStream();
ImageIO.write(bufferedImage, "jpeg", out);
out.flush();
out.close();
}
/**校验*/
@RequestMapping("/captcha/validate")
public void validate(HttpServletRequest request,
HttpServletResponse response) throws IOException {
String sessionId = request.getSession().getId();
String code = request.getParameter("code");
String validateResult = "fail";
try {
validateResult = CaptchaServiceSingleton.validate(sessionId, code)?"success":"fail";
} catch (Exception e) {
}
PrintWriter out=response.getWriter();
out.print(validateResult);
out.flush();
out.close();
}
}
前端代码 (基于jquery)
captcha.js
/**
* 验证码生成与校验面向对象js
*/
function Captcha(){}
Captcha.prototype={
init:function(image){
this.image=image; //验证码的image
this.generateUrl="http://localhost:8080/test/captcha/generate";//生成路径
this.validateUrl="http://localhost:8080/test/captcha/validate";//验证路径
this.realCode=null; //真实的验证码
return this;
},
/**生成*/
generate:function (){
this.realCode=null;
this.image.attr("src", this.generateUrl + "?" + Math.random());
},
/**校验*/
validate:function(code){
if(code == null || code == "" || code == "undefined" ){
return false
}
var _this = this;
if(_this.realCode!=code ){
var deferred =$.Deferred();//创建一个延迟对象，不然ajax方法return失效
$.ajax({
url:_this.validateUrl,
async: false,
data:"code="+code,
success:function(data){
if(data=="success"){
_this.realCode=code;
deferred.resolve();
}else{
_this.generate();
deferred.reject();
}
},
error:function(){
_this.generate();
deferred.reject();
}
});
return deferred.state() == "resolved" ? true : false;
}else{
return true;
}
}
}
html部分代码
//请事先引入jquery文件和自定义的captcha.js文件
<script type="text/javascript">
$(function() {
var captcha = new Captcha().init($("#captchaImg"));
captcha.generate();
$("#captchaImg").click(function(){
captcha.generate();
})
$("#validate_button").click(function(){
if (captcha.validate($("#captcha_code").val())) {
alert("验证码正确");
} else {
alert("验证码错误");
}
})
})
</script>
<div style="width:100%;height:600px;">
<img id="captchaImg" /></br> 验证码：<input id="captcha_code" /><br><br>
<button id="validate_button">校验</button>
</div>
测试结果如下
