1、login.jsp頁面程序
- <script type="text/javascript">
- function changeValidateCode(obj) {
- //獲取當前的時間作爲參數,無具體意義
- var timenow = new Date().getTime();
- //每次請求需要一個不同的參數,否則可能會返回同樣的驗證碼
- //這和瀏覽器的緩存機制有關係,也可以把頁面設置爲不緩存,這樣就不用這個參數了。
- obj.src="rand.action?d="+timenow;
- }
- </script>
- 在表單中添加下面這句話:
- <s:text name="random"></s:text>:<s:textfield name="rand" size="5"></s:textfield><img src="rand.action" onclick="changeValidateCode(this)" title="點擊圖片刷新驗證碼"/>
2、RandomNumUtil.java 生成驗證碼的類文件
- 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;// 圖像
- private String str;// 驗證碼
- private RandomNumUtil() {
- init();// 初始化屬性
- }
- /*
- * 取得RandomNumUtil實例
- */
- public static RandomNumUtil Instance() {
- return new RandomNumUtil();
- }
- /*
- * 取得驗證碼圖片
- */
- public ByteArrayInputStream getImage() {
- return this.image;
- }
- /*
- * 取得圖片的驗證碼
- */
- public String getString() {
- return this.str;
- }
- private void init() {
- // 在內存中創建圖象
- int width = 85, height = 20;
- BufferedImage image = new BufferedImage(width, height,
- BufferedImage.TYPE_INT_RGB);
- // 獲取圖形上下文
- Graphics g = image.getGraphics();
- // 生成隨機類
- Random random = new Random();
- // 設定背景色
- g.setColor(getRandColor(200, 250));
- g.fillRect(0, 0, width, height);
- // 設定字體
- g.setFont(new Font("Times New Roman", Font.PLAIN, 18));
- // 隨機產生155條幹擾線,使圖象中的認證碼不易被其它程序探測到
- 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);
- }
- // 取隨機產生的認證碼(6位數字)
- StringBuffer sRand = new StringBuffer();
- for (int i = 0; i < 6; i++) {
- String rand = String.valueOf(CHARS[random.nextInt(CHARS.length)]);
- sRand.append(rand);
- // 將認證碼顯示到圖象中
- g.setColor(new Color(20 + random.nextInt(110), 20 + random
- .nextInt(110), 20 + random.nextInt(110)));
- // 調用函數出來的顏色相同,可能是因爲種子太接近,所以只能直接生成
- g.drawString(rand, 13 * i + 6, 16);
- }
- // 賦值驗證碼
- this.str = sRand.toString();
- // 圖象生效
- 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("驗證碼圖片產生出現錯誤:" + e.toString());
- }
- this.image = input;/* 賦值圖像 */
- }
- /*
- * 給定範圍獲得隨機顏色
- */
- 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 生成驗證碼的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());//取得帶有隨機字符串的圖片
- ActionContext.getContext().getSession().put("random", rdnu.getString());//取得隨機字符串放入HttpSession
- return SUCCESS;
- }
- public void setInputStream(ByteArrayInputStream inputStream) {
- this.inputStream = inputStream;
- }
- public ByteArrayInputStream getInputStream() {
- return inputStream;
- }
- }
4、LoginAction.java 驗證驗證碼的action
- private String rand; //表單中的rand
- public String getRand() {
- return rand;
- }
- public void setRand(String rand) {
- this.rand = rand;
- }
- //從session中取出RandomAction.java 中生成的驗證碼random
- String arandom=(String)(ActionContext.getContext().getSession().get("random"));
- //下面就是將session中保存驗證碼字符串與客戶輸入的驗證碼字符串對比了
- 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驗證碼 -->
- <action name="rand" class="org.ml.rand.RandomAction">
- <result type="stream">
- <param name="contentType">image/jpeg</param>
- <param name="inputName">inputStream</param>
- </result>
- </action>