RandomCodeServlet.java
上传用户:zhc3n3
上传日期:2022-07-30
资源大小:2750k
文件大小:3k
源码类别:
WEB源码(ASP,PHP,...)
开发平台:
JavaScript
- package com.t11.web;
- import java.awt.Color;
- import java.awt.Font;
- import java.awt.Graphics;
- import java.awt.Graphics2D;
- import java.awt.image.BufferedImage;
- import java.io.IOException;
- import java.util.Random;
- import javax.servlet.ServletException;
- import javax.servlet.ServletOutputStream;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
- import com.sun.image.codec.jpeg.JPEGCodec;
- import com.sun.image.codec.jpeg.JPEGImageEncoder;
- /**
- * 验证码
- * @author student
- *
- */
- public class RandomCodeServlet extends HttpServlet{
- static StringBuffer randomCode;
- protected void doGet(HttpServletRequest request, HttpServletResponse response)
- throws ServletException, IOException {
- doPost(request,response);
- }
- protected void doPost(HttpServletRequest request, HttpServletResponse response)
- throws ServletException, IOException {
- //设置页面不缓存
- response.setHeader("Pragma", "No-cache");
- response.setHeader("Cache-Control", "no-cache");
- response.setDateHeader("Expires", 0);
- // 在内存中创建图象
- int width = 60, height = 20;
- BufferedImage image = new BufferedImage(width, height,
- BufferedImage.TYPE_INT_RGB);
- // 获取图形上下文
- Graphics g = image.getGraphics();
- //随机验证码
- String[] codes = { "0", "1", "2", "3", "4", "5", "6", "7", "8",
- "9", "q", "w", "e", "r", "t", "y", "u", "i", "o", "p", "a",
- "s", "d", "f", "g", "h", "j", "k", "l", "z", "x", "c", "v",
- "b", "n", "m", "Q", "W", "E", "R", "T", "Y", "U", "I", "O",
- "P", "A", "S", "D", "F", "G", "H", "J", "K", "L", "Z", "X",
- "C", "V", "B", "N", "M" };
- //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));
- //画边框
- //g.setColor(new Color());
- //g.drawRect(0,0,width-1,height-1);
- // 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(4位字符)
- String sRand = "";
- for (int i = 0; i < 4; i++) {
- int ix = random.nextInt(62);
- sRand += codes[ix];
- // String rand=String.valueOf(random.nextInt(10));
- //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)));
- g.drawString(codes[ix], 13 * i + 6, 16);
- }
- // 将认证码存入SESSION
- //将验证码保存到session中
- request.getSession().setAttribute("code", sRand);
- // 图象生效
- g.dispose();
- //响应流
- ServletOutputStream sos = response.getOutputStream();
- //图片编码器
- JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(sos);
- //响应输出
- encoder.encode(image);
- sos.close();
- // 输出图象到页面
- // ImageIO.write(image, "JPEG", response.getOutputStream());
- }
- public Color getRandColor(int fc, int bc) {//给定范围获得随机颜色
- 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);
- }
- }