
package com.abc.ufo.util;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.OutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
public class ImageMaker{
private char map[]={'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','1','2','3','4','5','6','7','8','9'};
public String getImage(int width,int height,OutputStream os){
BufferedImage image=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
Graphics g=image.getGraphics();
g.setColor(new Color(0xDCDCDC));
g.fillRect(0, 0, width, height);
StringBuilder sb=new StringBuilder();
for(int i=0;i<4;i++){
sb.append(map[(int)(map.length*Math.random())]);
}
String text=sb.toString();
g.setColor(Color.black);
g.setFont(new Font("Arial",Font.PLAIN,36));
g.setColor(Color.red);
String str=text.substring(0,1);
g.drawString(str, 18, 32);
g.setColor(Color.blue);
str=text.substring(1,2);
g.drawString(str, 60, 32);
g.setColor(Color.red);
str=text.substring(2,3);
g.drawString(str, 95, 32);
g.setColor(Color.blue);
str=text.substring(3,4);
g.drawString(str, 125, 32);
g.setColor(Color.gray);
Random rand=new Random();
for(int i=0;i<20;i++){
int x=rand.nextInt(width);
int y=rand.nextInt(height);
g.drawOval(x, y, width, height);
}
g.setColor(Color.black);
g.drawRect(0, 0, width-1, height-1);
//g.drawLine(width-2, 0, width-2, height);
g.dispose();
try{
ImageIO.write(image, "JPEG", os);
}catch(Exception e){
//e.printStackTrace();
}
return text;
}
}

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page contentType="image/jpeg" %>
<jsp:useBean id="image" scope="page" class="com.abc.ufo.util.ImageMaker"/>
<%
String str=image.getImage(160,40,response.getOutputStream());
session.setAttribute("verifyCode",str);
out.clear();
out = pageContext.pushBody();
%>
<div class="page-container">
<logic:present name="error">
<h2><bean:write name="error"/></h2>
</logic:present>
<h1>Login</h1>
<form action="login.html" method="post">
<input type="text" id="usernameTxt" name="username" class="username" placeholder="Username">
<input type="password" id="passwordTxt" name="password" class="password" placeholder="Password">
<input type="text" id="verifyCodeTxt" name="verifyCode" class="verifyCode" placeholder="Verification code">
<p><br/>No Zero in the verification code</p>
<img src="pages/user/login/image.jsp"/> <!-- 这个路径就是前面jsp的路径 -->
<button id="submitBtn">Sign me in</button>
<div class="error"><span>+</span></div>
</form>
<div class="connect" style="display:none">
<p>Or connect with:</p>
<p>
<a class="facebook" href=""></a>
<a class="twitter" href=""></a>
</p>
</div>
</div>