Java仿12306图片验证码

//选取8个图片
public static List<Object> getEightImages() {
 //保存取到的每一个图片的path，保证图片不会重复
 List<String> paths = new ArrayList<String>();
 
 File[] finalImages = new File[8];
 List<Object> object = new ArrayList<Object>();
 
 //保存tips
 String[] tips = new String[8];
 
 for (int i = 0; i < 8; i++) {
 //获取随机的二级目录
 int dirIndex = getRandom(secondaryDirNumbers);
 File secondaryDir = getFiles()[dirIndex];
  
 //随机到的文件夹名称保存到tips中
 tips[i] = secondaryDir.getName();
  
 //获取二级图片目录下的文件
 File[] images = secondaryDir.listFiles();
  
 int imageIndex = getRandom(imageRandomIndex);
 File image = images[imageIndex];
  
 //图片去重
 image = dropSameImage(image, paths, tips, i); 
  
 paths.add(image.getPath());
 
 finalImages[i] = image;
  
 }
 object.add(finalImages);
 object.add(tips);
 return object;
} 

//获取位置,返回的是第几个图片，而不是下标，从1开始,集合第一个元素为tip
 public static List<Object> getLocation(String[] tips) {
 List<Object> locations = new ArrayList<Object>();
 
 //获取Key分类
 String tip = getTip(tips);
 locations.add(tip);
  
 int length = tips.length;
 for (int i = 0; i < length; i++) {
  if (tip.equals(tips[i])) {
 
  locations.add(i+1);
  }
 }
 return locations;
 }
 

public static void mergeImage(File[] finalImages, HttpServletResponse response) throws IOException {
   
 //读取图片
 BufferedImage mergeImage = new BufferedImage(800, 400, BufferedImage.TYPE_INT_BGR);
  
 for (int i = 0; i < 8; i++) {
  File image = finalImages[i];
  
  BufferedImage bufferedImage = ImageIO.read(image);
  int width = bufferedImage.getWidth();
  int height = bufferedImage.getHeight();
  //从图片中读取RGB
  int[] imageBytes = new int[width*height];
  imageBytes = bufferedImage.getRGB(0, 0, width, height, imageBytes, 0, width);
  if ( i < 4) {
  mergeImage.setRGB(i*200, 0, width, height, imageBytes, 0, width);
  } else {
  mergeImage.setRGB((i -4 )*200, 200, width, height, imageBytes, 0, width);
  }  
  
 }
 
 
 ImageIO.write(mergeImage, "jpg", response.getOutputStream());
 //ImageIO.write(mergeImage, "jpg", destImage);
 }

response.setContentType("image/jpeg"); 
 response.setHeader("Pragma", "No-cache"); 
 response.setHeader("Cache-Control", "no-cache"); 
 response.setDateHeader("Expires", 0);
 
 List<Object> object = ImageSelectedHelper.getEightImages();
 File[] finalImages = (File[]) object.get(0);
 
 String[] tips = (String[]) object.get(1);
 //所有key的图片位置,即用户必须要选的图片
 List<Object> locations = ImageSelectedHelper.getLocation(tips);
 
 String tip = locations.get(0).toString();
 System.out.println(tip);
 session.setAttribute("tip", tip);
 locations.remove(0);
 
 int length = locations.size();
 for (int i = 0; i < length; i++) {
  System.out.println("实际Key图片位置:" + locations.get(i));
 }

 session.setAttribute("locations", locations);
 ImageMerge.mergeImage(finalImages, response);

<div><br> <div id="base"><br>  <img src="<%=request.getContextPath()%>/identify" style="width: 300px; height: 150px;" onclick="clickImg(event)" id="bigPicture"><br> </div><br> <br> </div><br><br>function clickImg(e) {
 var baseDiv = document.getElementById("base");
 var topValue = 0;
 var leftValue = 0;
 var obj = baseDiv;
 while (obj) {
  leftValue += obj.offsetLeft;
  topValue +=obj.offsetTop;
  obj = obj.offsetParent;
 }
 //解决firefox获取不到点击事件的问题
 var clickEvent = e ? e : (window.event ? window.event : null);
  
 var clickLeft = clickEvent.clientX + document.body.scrollLeft - document.body.clientLeft - 10;
 var clickTop = clickEvent.clientY + document.body.scrollTop - document.body.clientTop - 10;
 var divId = "img_" + index++;
 
 var divEle = document.createElement("div");
 
 divEle.setAttribute("id", divId);
 divEle.style.position = "relative";
 divEle.style.zIndex = index;
 divEle.style.width = "20px";
 divEle.style.height = "20px";
 divEle.style.display = "inline";
 
 divEle.style.top = clickTop - topValue - 150 + 10 + "px";
 divEle.style.left = clickLeft - leftValue - 300 + "px";
 
 divEle.setAttribute("onclick", "remove('" + divId + "')");
 baseDiv.appendChild(divEle);
 
 var imgEle = document.createElement("img");
 imgEle.src = "<%=request.getContextPath()%>/resources/timo.png";
 imgEle.style.width = "20px";
 imgEle.style.height = "20px";
 imgEle.style.top = "0px";
 imgEle.style.left = "0px";
 imgEle.style.position = "absolute";
 imgEle.style.zIndex = index;
 divEle.appendChild(imgEle);
 }

public List<Integer> isPass(String result) {
  
 String[] xyLocations = result.split(",");
 //保存用户选择的坐标落在哪些图片上
 List<Integer> list = new ArrayList<Integer>();
 //每一组坐标
 System.out.println("用户选择图片数:"+xyLocations.length);
 for (String xyLocation : xyLocations) {
  String[] xy = xyLocation.split("\\|\\|");
  int x = Integer.parseInt(xy[0]);
  int y = Integer.parseInt(xy[1]);
  
  //8,4图片区间
  if ( x > -75 && x <= 0) {
 
  if ( y > -75 && y <= 0) { //8号
   list.add(8);
 
  } else if ( y >= -150 && y <= -75 ) { //4号
   list.add(4);
  }
  } else if ( x > -150 && x <= -75) { //7,3图片区间
   
  if ( y > -75 && y <= 0) { //7号
   list.add(7);
 
  } else if ( y >= -150 && y <= -75 ) { //3号
   list.add(3);
  }
  } else if ( x > -225 && x <= -150) { //6,2图片区间
   
  if ( y > -75 && y <= 0) { //6号
   list.add(6);
 
  } else if ( y >= -150 && y <= -75 ) { //2号
   list.add(2);
  }
   
  } else if ( x >= -300 && x <= -225) { //5,1图片区间
   
  if ( y > -75 && y <= 0) { //5号
   list.add(5);
 
  } else if ( y >= -150 && y <= -75 ) { //1号
   list.add(1);
  }
  } else {
  return null;
  }
 }
 return list;
 }

function refresh() {
 var url = "<%=request.getContextPath()%>/identify";
 var xhr = new XMLHttpRequest();
 xhr.open('GET', url, true);
 xhr.responseType = "blob";
 xhr.onload = function() {
 if (this.status == 200) {
  var blob = this.response;  
  //加载成功后释放blob
  bigPicture.onload = function(e) {
  window.URL.revokeObjectURL(bigPicture.src);
  };
  bigPicture.src = window.URL.createObjectURL(blob);
 }
 }
 xhr.send();