如果我们想用JAVA中BufferedImage画出漂亮的验证码点击变化怎么实现呢，类似这样：
点击变化，以下是实现过程，直接上代码：
首先前台：<i><img style="height:22px;" id="zcodeImg" alt="点击更换" title="点击更换" src="" /></i>放在你页面想展示的位置;接着页面加载时
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$(document).ready(function() {
changeCode1();
$("#codeImg").bind("click", changeCode1);
});
function changeCode1() {
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js部分写完了，现在是控制层，直接上代码：
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@Controller@RequestMapping("/code")
public class SecCodeController { @RequestMapping
public void generate(HttpServletResponse response){
ByteArrayOutputStream output = new ByteArrayOutputStream();
String code = drawImg(output);
Subject currentUser = SecurityUtils.getSubject();
Session session = currentUser.getSession();
session.setAttribute(Const.SESSION_SECURITY_CODE, code);
try {
ServletOutputStream out = response.getOutputStream();
output.writeTo(out);
out.close();
} catch (IOException e) {
//e.printStackTrace();
}
}
private String drawImg(ByteArrayOutputStream output){
String code = "";
for(int i=0; i<4; i++){
code += randomChar();
}
int width = 70;
int height = 25;
BufferedImage bi = new BufferedImage(width,height,BufferedImage.TYPE_3BYTE_BGR);
Font font = new Font("Times New Roman",Font.PLAIN,20);
Graphics2D g = bi.createGraphics();
g.setFont(font);
Color color = new Color(66,2,82);
g.setColor(color);
g.setBackground(new Color(226,226,240));
g.clearRect(0, 0, width, height);
FontRenderContext context = g.getFontRenderContext();
Rectangle2D bounds = font.getStringBounds(code, context);
double x = (width - bounds.getWidth()) / 2;
double y = (height - bounds.getHeight()) / 2;
double ascent = bounds.getY();
double baseY = y - ascent;
g.drawString(code, (int)x, (int)baseY);
g.dispose();
try {
ImageIO.write(bi, "jpg", output);
} catch (IOException e) {
//e.printStackTrace();
}
return code;
}
private char randomChar(){
Random r = new Random();
String s = "ABCDEFGHJKLMNPRSTUVWXYZ0123456789";
return s.charAt(r.nextInt(s.length()));
}
} |