Java实现Web页面前数字字母验证码实现 推荐

<ul>
<li><label>验证码：</label></li>
<li>
<div>
<input  type="text" name="validateCode"  class="login_input" value=""/>
<img  id="img" src="${baseURL }/validateCode" onclick="onclickValidateCode(this);" />
</div>
</li>
</ul>

<script type="text/javascript" language="javascript">

//请求获取验证码
function onclickValidateCode(obj){
$(obj).attr("src","${baseURL }/validateCode?"+new Date().getTime());
}

</script>

package com.njcc.pay.controller.login;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.math.NumberUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

import com.alibaba.dubbo.common.utils.StringUtils;

/**
* 验证马  Controller
*
* @author Administrator
*
*/
@Controller
public class ValidateCodeController {

@SuppressWarnings("unused")
private static final Log LOG = LogFactory.getLog(ValidateCodeController.class);

public static final String VALIDATE_CODE = "validateCode";
private int w = 70;
private int h = 23;

/**
* @throws Exception
* 函数功能说明 ： 进入后台登陆页面.
*
* @参数： @return
* @return String
* @throws
*/
@RequestMapping(value = "/validateCode")
public void validateCode(HttpServletRequest request,
HttpServletResponse response) throws Exception {
createImage(request,response);
}

private void createImage(HttpServletRequest request,HttpServletResponse response) throws IOException {
response.setHeader("Pragma", "no-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
response.setContentType("image/jpeg");

String width = request.getParameter("width");
String height = request.getParameter("height");
if (StringUtils.isNumeric(width) && StringUtils.isNumeric(height)) {
w = NumberUtils.toInt(width);
h = NumberUtils.toInt(height);
}

BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics();

/*
* 生成背景
*/
createBackground(g);

/*
* 生成字符
*/
String s = createCharacter(g);
request.getSession().setAttribute(VALIDATE_CODE, s);

g.dispose();
OutputStream out = response.getOutputStream();
ImageIO.write(image, "JPEG", out);
out.close();

}
/**
* 生成颜色
* @param fc
* @param bc
* @return
*/
private Color getRandColor(int fc,int bc) {
int f = fc;
int b = bc;
Random random=new Random();
if(f>255) {
f=255;
}
if(b>255) {
b=255;
}
return new Color(f+random.nextInt(b-f),f+random.nextInt(b-f),f+random.nextInt(b-f));
}

/**
* 生成背景
* @param g
*/
private void createBackground(Graphics g) {
// 填充背景
g.setColor(getRandColor(220,250));
g.fillRect(0, 0, w, h);
// 加入干扰线条
for (int i = 0; i < 8; i++) {
g.setColor(getRandColor(40,150));
Random random = new Random();
int x = random.nextInt(w);
int y = random.nextInt(h);
int x1 = random.nextInt(w);
int y1 = random.nextInt(h);
g.drawLine(x, y, x1, y1);
}
}

/**
* 生成字符
* @param g
* @return
*/
private String createCharacter(Graphics g) {
char[] codeSeq = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J',
'K', 'M', 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',
'X', 'Y', 'Z', '2', '3', '4', '5', '6', '7', '8', '9' };
String[] fontTypes = {"Arial","Arial Black","AvantGarde Bk BT","Calibri"};
Random random = new Random();
StringBuilder s = new StringBuilder();
for (int i = 0; i < 4; i++) {
String r = String.valueOf(codeSeq[random.nextInt(codeSeq.length)]);//random.nextInt(10));
g.setColor(new Color(50 + random.nextInt(100), 50 + random.nextInt(100), 50 + random.nextInt(100)));
g.setFont(new Font(fontTypes[random.nextInt(fontTypes.length)],Font.BOLD,26));
g.drawString(r, 15 * i + 5, 19 + random.nextInt(8));
//			g.drawString(r, i*w/4, h-5);
s.append(r);
}
return s.toString();
}

}