servlet awt随机图片验证码
package rd.test; 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.imageio.ImageIO; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; //输出一张图片 public class Test1 extends HttpServlet { public static final int WIDTH = 120; public static final int HEIGHT = 35; public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { BufferedImage image = new BufferedImage(WIDTH,HEIGHT,BufferedImage.TYPE_INT_RGB); Graphics g = image.getGraphics(); //1,设置背景色 setBackGround(g); //2,设置边框 setBorder(g); //3,画干扰线 drowRandomLine(g); //4,写随机数 //drawRandomNum(g); String random = drawRandomNum2d((Graphics2D)g);//验证相关 request.getSession().setAttribute("checkcode",random);//验证相关
//5,图形写给浏览器 response.setContentType("image/jpeg"); //控制浏览器不要缓存随机验证码图片,让它每次都更新 response.setDateHeader("expries", -1); response.setHeader("Cache-Control","no-cache"); response.setHeader("Pragma","no-cache"); ImageIO.write(image, "jpg", response.getOutputStream()); } private void drowRandomLine(Graphics g) { // TODO Auto-generated method stub g.setColor(Color.GRAY); for(int i = 0;i<5;i++) { int x1 = new Random().nextInt(WIDTH-2)+2; int y1 = new Random().nextInt(HEIGHT-2)+2; int x2 = new Random().nextInt(WIDTH-2)+2; int y2 = new Random().nextInt(HEIGHT-2)+2; g.drawLine(x1, y1, x2, y2); } } private String drawRandomNum2d(Graphics2D g) { // TODO Auto-generated method stub g.setColor(Color.RED); g.setFont(new Font("宋体",Font.BOLD,20)); //[\u4e00-\u9fa5] String base = "一二三四五六七八九十百千万兆亿啊我饿依无余"; StringBuffer sb = new StringBuffer();//验证相关
int x = 5; for(int i = 0;i<4;i++) { int degree = new Random().nextInt()%30; String ch = "" + base.charAt(new Random().nextInt(base.length())); sb.append(ch);//验证相关
g.rotate(degree*Math.PI/180, x, 25);//设置旋转幅度 g.drawString(ch, x, 25); g.rotate(-degree*Math.PI/180, x, 25);//转回去 x+=30; }
return sb.toString(); } private void drawRandomNum(Graphics g) { g.setColor(Color.RED); g.setFont(new Font("宋体",Font.BOLD,20)); //[\u4e00-\u9fa5] String base = "一二三四五六七八九十百千万兆亿啊我饿依无余"; int x = 5; for(int i = 0;i<4;i++) { String ch = "" + base.charAt(new Random().nextInt(base.length())); g.drawString(ch, x, 20); x+=30; } } private void setBorder(Graphics g) { g.setColor(Color.BLUE); g.drawRect(1, 1, WIDTH-2, HEIGHT-2); } private void setBackGround(Graphics g) { // TODO Auto-generated method stub g.setColor(Color.WHITE); g.fillRect(0, 0, WIDTH, HEIGHT); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { } }
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <base href="<%=basePath%>"> <title>My JSP 'index.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> <script type="text/javascript"> function changeImg(img){ img.src = img.src + "?" + new Date().getTime(); } </script> </head> <body> <form action="/web/servlet/check" method="post"> 用户名:<input type="text" name="username"> 密码 :<input type="password" name="password"><br/><br/> 验证码:<input type = "text" name="checkcode"> <img src="http://localhost:8080/random/servlet/Test1" onclick="changeImg(this)"/> <input type="submit" value="注册"> </form> </body> </html>
check:
request.setCharacterEncoding("UTF-8");
String c_checkcode = request.getParameter("checkcode");
String s_checkcode = request.getSession().getAttribut("checkcode");
if(c_checkcode!=null && s_checkcode!=null && c_checkcode.equals(s_checkcode)){
System.out.println("处理注册请求“);
}else{
System.out.println("验证码错误");
}