struts2实现验证码还是很方便的。struts确实给我们带来了很多的方便之处。
1：AuthCode.java是用来生成验证码图片的：
public class AuthCode {
private ByteArrayInputStream input;
private ByteArrayOutputStream output;
private String code;// 验证码
private int codeNum;// 验证码字符数量
private int width;
private int height;
// 构造器
private AuthCode(int width, int height, int codeNum) {
this.width = width;
this.height = height;
this.codeNum = codeNum;
if (width < 15 * codeNum + 6) {
this.width = 13 * codeNum + 6;
}
if (height < 20) {
this.height = 20;
}
buildImage();
}
// 以字符串形式返回验证码
public String getCode() {
return code;
}
// 以输入流的形式返回验证图片
public ByteArrayInputStream getIamgeAsInputStream() {
return input;
}
// 以输出流的形式返回验证图片
public ByteArrayOutputStream getImageAsOuputStream() {
return output;
}
// 创建默认大小的验证码
public static AuthCode createInstance() {
return new AuthCode(85, 20, 4);
}
// 创建指定大小的验证码
public static AuthCode createInstance(int width, int height, int codeNum) {
return new AuthCode(width, height, codeNum);
}
// 生成验证码图片
private void buildImage() {
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
// 生成随机类
Random random = new Random();
// 设定背景色
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);
// 设定字体
g.setFont(new Font("Times New Roman", Font.PLAIN, 18));
// 随机产生150条干扰线，使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 150; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}
// 取随机产生的认证码
String codes = "ABCDEFGHJKLMNOPQRSTUVWXYZ23456789";
String sRand = "";
for (int i = 0; i < codeNum; i++) {
String rand = codes.charAt(random.nextInt(codes.length())) + "";
sRand += rand;
// 将认证码显示到图象中
g.setColor(new Color(20 + random.nextInt(110), 20 + random
.nextInt(110), 20 + random.nextInt(110)));
// 将字符串绘制到图片上
g.drawString(rand, i * (width / codeNum) + 6, (int)((height+12)/2));
}
/* 验证码赋值 */
this.code = sRand;
// 图象生效
g.dispose();
try {
output = new ByteArrayOutputStream();
ImageOutputStream imageOut = ImageIO
.createImageOutputStream(output);
ImageIO.write(image, "JPEG", imageOut);
imageOut.close();
input = new ByteArrayInputStream(output.toByteArray());
} catch (Exception e) {
System.out.println("验证码图片产生出现错误：" + e.toString());
}
}
// 获取随机颜色
private Color getRandColor(int fc, int bc) {
Random random = new Random();
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + random.nextInt(bc - fc);
int g = fc + random.nextInt(bc - fc);
int b = fc + random.nextInt(bc - fc);
return new Color(r, g, b);
}
}
下面的是action中的调用方法：
public InputStream getInputStream(){
AuthCode code = AuthCode.createInstance();
HttpServletRequest request = ServletActionContext.getRequest();
HttpSession seesion = request.getSession();
// session.put("authCode", code.getCode());
seesion.setAttribute("authcode", code.getCode());
return code.getIamgeAsInputStream();
}
public String execute(){
return "success";
}
?上面代码将生成的code放入session中了，这样在验证的时候就可以进行equals了。在action对应的.xml文件中得设置struts提供的stream模式来处理result
<action name="authcode" class="project.action.ImageAction" method="execute"> <result name="success" type="stream"> <param name="contentType">image/jpeg</param> </result> </action>
?然后还要在使用验证码图片的页面上添加链接：
<tr>
<td width="13%" height="35" ><span class="login_txt">验证码</span></td>
<td height="35" colspan="2" class="top_hui_text">
<input class="wenbenkuang" name="authCode" type="text" value="" maxLength="4" size="10">
<img src="authcode.action" alt="验证码" style="cursor:hand" title="看不清楚?换一张" onclick="changeImage(this)"/>
<label class="login_txt_bt">${authcode_msg }</label>
</td>
</tr>
?这样就可以显示随机验证码图片了。
当然在做登录的时候需要验证码图片，这个用struts2真是so easy啊：下面的是登录的action，因为写的比较赶，就很随便了：
public String login(){
String flag = "";
HttpServletRequest request = ServletActionContext.getRequest();
HttpSession session = request.getSession();
String code = (String) session.getAttribute("authcode");
if(authCode != null & authCode.toUpperCase().equals(code)){
if(pd.queryLogin(power.getUserName(), power.getPassword()) == true){
// session.put("power",power);
power = pd.queryByName(power.getUserName());
session.setAttribute("power", power);
System.out.println(pd.queryByName(power.getUserName()).getPowerset());
if((pd.queryByName(power.getUserName()).getPowerset()).equals("1111")){
flag = "admin";
System.out.println(flag);
}else{
flag = "adminlimit";
System.out.println(flag);
}
}else{
flag = "fail";
}
}else{
authcode_msg = "验证码错误";
flag = "error";
}
return flag;
}
?
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