package com.hywl.servlet;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
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 javax.servlet.http.HttpSession;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
/**
* @author MrWang
**/
public class ImageValidServlet extends HttpServlet {
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
Random random=new Random();
response.setContentType("image/jpeg");
int width=70,height=20;
BufferedImage bi=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
Graphics g=bi.getGraphics();
g.setColor(getRandColor(200, 255));
g.fillRect(0, 0, width,height);
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);
}
String strRandom="";
String generateRandom="23456789abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ";
for(int i=0;i<4;i++){
int intRandom=random.nextInt(55);
String numRandom=generateRandom.charAt(intRandom)+"";
strRandom+=numRandom;
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
g.setFont(new Font("Time NewRoman",Font.BOLD,14+random.nextInt(6)));
g.drawString(numRandom,6+13*i, 16);
}
HttpSession session=request.getSession();
session.setAttribute("strRandom", strRandom);
g.dispose();
ServletOutputStream sos=response.getOutputStream();
JPEGImageEncoder encoder=JPEGCodec.createJPEGEncoder(sos);
encoder.encode(bi);
sos.close();
bi=null;
}
public 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);
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.doGet(request, response);
}
}
页面调用
<script type=text/javascript>
var i=0;
function changeImg(img)
{
img.src="<%=request.getContextPath()%>/ImageValidServlet?i="+i;
i++;
}
</script>
<img style="cursor:hand;border:none;}" id="validcode"
name="validcode" src="<%=request.getContextPath()%>/ImageValidServlet" align="absmiddle" onclick="changeImg(this)"/>
|
|
收藏
淘帖
踩
