1、login.jsp页面程序
- <script type="text/javascript">
- function changeValidateCode(obj) {
- //获取当前的时间作为参数,无具体意义
- var timenow = new Date().getTime();
- //每次请求需要一个不同的参数,否则可能会返回同样的验证码
- //这和浏览器的缓存机制有关系,也可以把页面设置为不缓存,这样就不用这个参数了。
- obj.src="rand.action?d="+timenow;
- }
- </script>
- 在表单中添加下面这句话:
- <s:text name="random"></s:text>:<s:textfield name="rand" size="5"></s:textfield><img src="rand.action" onclick="changeValidateCode(this)" title="点击图片刷新验证码"/>
2、RandomNumUtil.java 生成验证码的类文件
- package org.ml.util;
- import java.awt.Color;
- import java.awt.Font;
- import java.awt.Graphics;
- import java.awt.image.BufferedImage;
- import java.io.ByteArrayInputStream;
- import java.io.ByteArrayOutputStream;
- import java.util.Random;
- import javax.imageio.ImageIO;
- import javax.imageio.stream.ImageOutputStream;
- public class RandomNumUtil {
- public static final char[] CHARS = { '2', '3', '4', '5', '6', '7', '8',
- '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M',
- 'N', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
- private ByteArrayInputStream image;// 图像
- private String str;// 验证码
- private RandomNumUtil() {
- init();// 初始化属性
- }
- /*
- * 取得RandomNumUtil实例
- */
- public static RandomNumUtil Instance() {
- return new RandomNumUtil();
- }
- /*
- * 取得验证码图片
- */
- public ByteArrayInputStream getImage() {
- return this.image;
- }
- /*
- * 取得图片的验证码
- */
- public String getString() {
- return this.str;
- }
- private void init() {
- // 在内存中创建图象
- int width = 85, height = 20;
- 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155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 < 155; 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(6位数字)
- StringBuffer sRand = new StringBuffer();
- for (int i = 0; i < 6; i++) {
- String rand = String.valueOf(CHARS[random.nextInt(CHARS.length)]);
- sRand.append(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)));
- // 调用函数出来的颜色相同,可能是因为种子太接近,所以只能直接生成
- g.drawString(rand, 13 * i + 6, 16);
- }
- // 赋值验证码
- this.str = sRand.toString();
- // 图象生效
- g.dispose();
- ByteArrayInputStream input = null;
- ByteArrayOutputStream output = new ByteArrayOutputStream();
- try {
- 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());
- }
- this.image = input;/* 赋值图像 */
- }
- /*
- * 给定范围获得随机颜色
- */
- 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);
- }
- }
3、RandomAction.java 生成验证码的action程序
- import java.io.ByteArrayInputStream;
- import org.ml.util.RandomNumUtil;
- import com.opensymphony.xwork2.ActionContext;
- import com.opensymphony.xwork2.ActionSupport;
- public class RandomAction extends ActionSupport{
- private ByteArrayInputStream inputStream;
- public String execute() throws Exception{
- RandomNumUtil rdnu=RandomNumUtil.Instance();
- this.setInputStream(rdnu.getImage());//取得带有随机字符串的图片
- ActionContext.getContext().getSession().put("random", rdnu.getString());//取得随机字符串放入HttpSession
- return SUCCESS;
- }
- public void setInputStream(ByteArrayInputStream inputStream) {
- this.inputStream = inputStream;
- }
- public ByteArrayInputStream getInputStream() {
- return inputStream;
- }
- }
4、LoginAction.java 验证验证码的action
- private String rand; //表单中的rand
- public String getRand() {
- return rand;
- }
- public void setRand(String rand) {
- this.rand = rand;
- }
- //从session中取出RandomAction.java 中生成的验证码random
- String arandom=(String)(ActionContext.getContext().getSession().get("random"));
- //下面就是将session中保存验证码字符串与客户输入的验证码字符串对比了
- if(arandom.equals(this.getRand())) {
- ActionContext.getContext().getSession().put("user", this.getUsername());
- return SUCCESS;
- }
- else {
- return ERROR;
- }
5、配置struts.xml文件
- <!-- Random验证码 -->
- <action name="rand" class="org.ml.rand.RandomAction">
- <result type="stream">
- <param name="contentType">image/jpeg</param>
- <param name="inputName">inputStream</param>
- </result>
- </action>