1. 前台页面代码： 页面刷新时会自动请求 ${pageContext.request.contextPath}/yanzheng?yz=&time=-1111 这个action
<form name="f" action="" method="post">
用户名 ： <input id="name" type="text" name="userDTO.userName" /><br>
密 码 ： <input type="password" name="userDTO.passWord" /><br>
验证码 ： <input type="checkCode" name="userDTO.checkCode" /><br>
<img id="myzmDiv" src="${pageContext.request.contextPath}/yanzheng?yz=&time=-1111" onClick="yanZhengMa()" style="width: 80px; height: 40px; border-radius: 4px">
<input type="button" value="submit1" onclick="javascript:document.f.action='user/login';document.f.submit();" />
</form>
<!-- 点击图片同样请求这个 action 进行刷新验证码， 需要传入一个当前时间戳， 避免缓存不更新， 变量yz没用， 懒得删 -->
<script type="text/javascript">
function yanZhengMa(){
var yz = "";
$("#myzmDiv").attr("src","${pageContext.request.contextPath}/yanzheng?yz="+yz+"&time="+new Date());
}
</script>
2. struts.xml配置文件 不需要result标签返回， 会自动返回到 请求页面
<package name="user2" namespace="/" extends="struts-default">
<action name="yanzheng" class="com.test.actions.YanzhengAction" method="yanzhengma" />
</package>
3. yanzhengma 方法实现 会将随机生成的数字图片发回到请求页面， 并且会将生成的数字存储到 session中， key 和 value 都是生成的随机数
public String yanzhengma() throws IOException {
//"{\"code\":501,\"info\":\"已经在业务中使用,不能删除\"}";
HttpSession session = ServletActionContext.getRequest().getSession();
String code="";
Captcha cha=new SpecCaptcha();
char[] shu=cha.alphas();
for(int i=0;i<shu.length;i++){
code+=shu[i]+"";
}
Captcha captcha = new SpecCaptcha(58,28,4,shu);// gif格式动画验证码
HttpServletResponse response = ServletActionContext.getResponse();
ServletOutputStream out = response.getOutputStream();
captcha.out(out);
session.setAttribute(code, code);
out.flush();
out.close();
return null;
}3-1 > 附属类： Captcha.java
package com.test.Util; import java.awt.Color;
import java.awt.Font;
import java.io.OutputStream; public abstract class Captcha
{
protected Font font = new Font("Verdana", Font.ITALIC|Font.BOLD, 18); // 字体
protected int len = 4; // 验证码随机字符长度
protected int width = 78; // 验证码显示跨度
protected int height = 30; // 验证码显示高度
private String chars = null; // 随机字符串
protected char[] shu;
/**
* 生成随机字符数组
* @return 字符数组
*/
public char[] alphas()
{
char[] cs = new char[len];
for(int i = 0;i<len;i++)
{
cs[i] = Randoms.alpha();
}
chars = new String(cs);
return cs;
}
public Font getFont()
{
return font;
} public void setFont(Font font)
{
this.font = font;
} public int getLen()
{
return len;
} public void setLen(int len)
{
this.len = len;
} public int getWidth()
{
return width;
} public void setWidth(int width)
{
this.width = width;
} public int getHeight()
{
return height;
} public void setHeight(int height)
{
this.height = height;
} public String getChars() {
return chars;
}
public void setChars(String chars) {
this.chars = chars;
}
public char[] getShu() {
return shu;
}
public void setShu(char[] shu) {
this.shu = shu;
}
/**
* 给定范围获得随机颜色
* @return Color 随机颜色
*/
protected Color color(int fc, int bc)
{
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + Randoms.num(bc - fc);
int g = fc + Randoms.num(bc - fc);
int b = fc + Randoms.num(bc - fc);
return new Color(r, g, b);
}
/**
* 验证码输出,抽象方法，由子类实现
* @param os 输出流
*/
public abstract void out(OutputStream os); /**
* 获取随机字符串
* @return string
*/
public String text()
{
return chars;
}
}
3-2 > 附属类： Randoms.java
package com.test.Util;
import java.util.Random;
/**
* <p>随机工具类</p>
*
* @author: wuhongjun
* @version:1.0
*/
public class Randoms
{
private static final Random RANDOM = new Random();
//定义验证码字符.去除了O和I等容易混淆的字母
/* public static final char ALPHA[]={'A','B','C','D','E','F','G','H','G','K','M','N','P','Q','R','S','T','U','V','W','X','Y','Z'
,'a','b','c','d','e','f','g','h','i','j','k','m','n','p','q','r','s','t','u','v','w','x','y','z','2','3','4','5','6','7','8','9'}; */
public static final char ALPHA[]={'1','2','3','4','5','6','7','8','9'};
/**
* 产生两个数之间的随机数
* @param min 小数
* @param max 比min大的数
* @return int 随机数字
*/
public static int num(int min, int max)
{
return min + RANDOM.nextInt(max - min);
}
/**
* 产生0--num的随机数,不包括num
* @param num 数字
* @return int 随机数字
*/
public static int num(int num)
{
return RANDOM.nextInt(num);
}
public static char alpha()
{
return ALPHA[num(0, ALPHA.length)];
}
} 3-3 > 附属类： SpecCaptcha.java
package com.test.Util;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.OutputStream; import javax.imageio.ImageIO; /**
* <p>png格式验证码</p>
*
* @author: wuhongjun
* @version:1.0
*/
public class SpecCaptcha extends Captcha
{
public SpecCaptcha()
{
}
public SpecCaptcha(int width, int height)
{
this.width = width;
this.height = height;
}
public SpecCaptcha(int width, int height, int len,char[] shu){
this(width,height);
this.len = len;
this.shu=shu;
}
public SpecCaptcha(int width, int height, int len, Font font,char[] shu){
this(width,height,len,shu);
this.font = font;
}
/**
* 生成验证码
* @throws java.io.IOException IO异常
*/
@Override
public void out(OutputStream out){
graphicsImage(this.shu, out);
} /**
* 画随机码图
* @param strs 文本
* @param out 输出流
*/
private boolean graphicsImage(char[] strs, OutputStream out){
boolean ok = false;
try
{
BufferedImage bi = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
Graphics2D g = (Graphics2D)bi.getGraphics();
AlphaComposite ac3;
Color color ;
int len = strs.length;
g.setColor(Color.WHITE);
g.fillRect(0,0,width,height);
// 随机画干扰的蛋蛋
for(int i=0;i<15;i++){
color = color(150, 250);
g.setColor(color);
g.drawOval(Randoms.num(width), Randoms.num(height), 5+Randoms.num(10), 5+Randoms.num(10));// 画蛋蛋，有蛋的生活才精彩
color = null;
}
g.setFont(font);
int h = height - ((height - font.getSize()) >>1),
w = width/len,
size = w-font.getSize()+1;
/* 画字符串 */
for(int i=0;i<len;i++)
{
ac3 = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.7f);// 指定透明度
g.setComposite(ac3);
color = new Color(20 + Randoms.num(110), 20 + Randoms.num(110), 20 + Randoms.num(110));// 对每个字符都用随机颜色
g.setColor(color);
g.drawString(strs[i]+"",(width-(len-i)*w)+size, h-4);
color = null;
ac3 = null;
}
ImageIO.write(bi, "png", out);
out.flush();
ok = true;
}catch (IOException e){
ok = false;
}finally
{
Streams.close(out);
}
return ok;
}
}
3-3 > 附属类： Streams.java
package com.test.Util; import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream; public class Streams { /** * 关闭输入流 * @param in 输入流 */ public static void close(InputStream in) { if (in != null) { try { in.close(); } catch (IOException ioex) { // ignore } } } /** * 关闭输出流 * @param out 输出流 */ public static void close(OutputStream out) { if (out != null) { try { out.flush(); } catch (IOException ioex) { // ignore } try { out.close(); } catch (IOException ioex) { // ignore } } } }
4. 点击登录按钮后 后台action 校验 验证码是否正确 （userDTO.getCheckCode() 获取前台页面传递过来的 用户输入的验证码）
public String login() {
HttpSession session2 = ServletActionContext.getRequest().getSession();
String checkCode = (String)session2.getAttribute(userDTO.getCheckCode());
if(checkCode == null) {
return "login";
}else {
return "welcome";
}
}