几种JSP彩色验证码的实现
JSP彩色验证码的实现
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.util.Random;
import javax.imageio.ImageIO;
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;
public class ImageServlet extends HttpServlet {
// 验证码图片的宽度。
private int width=60;
//验证码图片的高度。
private int height=20;
protected void service(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, java.io.IOException
{
BufferedImage buffimg=new BufferedImage(width,height,
BufferedImage.TYPE_INT_RGB);
Graphics2D g=buffimg.createGraphics();
//创建一个随机数生成器类。
Random random=new Random();
g.setColor(Color.white);
g.fillRect(0,0,width,height);
//创建字体，字体的大小应该根据图片的高度来定。
Font font=new Font("times new roman",Font.PLAIN,18);
//设置字体。
g.setFont(font);
//画边框。
g.setColor(Color.black);
g.drawRect(0,0,width-1,height-1);
//随机产生160条干扰线，使图象中的认证码不易被其它程序探测到。
g.setColor(Color.gray);
for (int i=0;i<10;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);
}
//randomcode用于保存随机产生的验证码，以便用户登录后进行验证。
StringBuffer randomcode=new StringBuffer();
int red=0,green=0,blue=0;
//随机产生4位数字的验证码。
for (int i=0;i<4;i++)
{
//得到随机产生的验证码数字。
String strrand=String.valueOf(random.nextInt(10));
//产生随机的颜色分量来构造颜色值，这样输出的每位数字的颜色值都将不同。
red=random.nextInt(200);
green=random.nextInt(200);
blue=random.nextInt(200);
//产生随机高度 13至height之间
float imght = 0;
while(imght<=12){
imght = Float.parseFloat(String.valueOf(random.nextInt(height)));
}
//用随机产生的颜色将验证码绘制到图像中。
g.setColor(new Color(red,green,blue));
g.drawString(strrand,13*i+6,imght);
//将产生的四个随机数组合在一起。
randomcode.append(strrand);
}
//将四位数字的验证码保存到session中。
HttpSession session=req.getSession();
session.setAttribute("VerifyCode",randomcode.toString());
//禁止图像缓存。
resp.setHeader("pragma","no-cache");
resp.setHeader("cache-control","no-cache");
resp.setDateHeader("expires", 0);
resp.setContentType("image/jpeg");
//将图像输出到servlet输出流中。
ServletOutputStream sos=resp.getOutputStream();
ImageIO.write(buffimg, "jpeg",sos);
sos.close();
}
}
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jsp注册验证码的生成
image.jsp(用来生成验证码)，数字验证码
<%@ page contentType="image/jpeg" import="java.awt.*, java.awt.image.*,java.util.*,javax.imageio.*" pageEncoding="UTF-8"%>
<%@ page import="java.io.OutputStream" %>
<%!
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);
}
%>
<%
try{
response.setHeader("Pragma","No-cache");
response.setHeader("Cache-Control","no-cache");
response.setDateHeader("Expires", 0);
int width=60, height=20;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
OutputStream os=response.getOutputStream();
Graphics g = image.getGraphics();
Random random = new Random();
g.setColor(getRandColor(200,250));
g.fillRect(0, 0, width, height);
g.setFont(new Font("Times New Roman",Font.PLAIN,18));
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 sRand="";
for (int i=0;i<4;i++){
String rand=String.valueOf(random.nextInt(10));
sRand+=rand;
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
g.drawString(rand,13*i+6,16);
}
session.setAttribute("code",sRand);
g.dispose();
ImageIO.write(image, "JPEG",os);
os.flush();
os.close();
os=null;
response.flushBuffer();
out.clear();
out = pageContext.pushBody();
}
catch(IllegalStateException e)
{
System.out.println(e.getMessage());
e.printStackTrace();
}%>
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image.jsp(生成中文验证码)
<%@page contentType="image/jpeg" pageEncoding="UTF-8" import="java.awt.*,java.awt.image.*,java.util.*,javax.imageio.*"%>
<%!
//生成随机颜色
Color getRandColor(Random random, int fc, int bc) {
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);
}
%>
<%
//设置页面不缓存
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
// 设置图片的长宽
int width = 176, height = 30;
//设置备选汉字，剔除一些不雅的汉字
String base = "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";
//备选汉字的长度
int length = base.length();
//创建内存图像
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
//创建随机类的实例
Random random = new Random();
// 设定图像背景色(因为是做背景，所以偏淡)
g.setColor(getRandColor(random, 200, 250));
g.fillRect(0, 0, width, height);
//备选字体
String[] fontTypes = {
"u5b8bu4f53", "u65b0u5b8bu4f53", "u9ed1u4f53", "u6977u4f53", "u96b6u4e66"};
int fontTypesLength = fontTypes.length;
//在图片背景上增加噪点
g.setColor(getRandColor(random, 160, 200));
g.setFont(new Font("Times New Roman", Font.PLAIN, 14));
for (int i = 0; i < 6; i++) {
g.drawString("*********************************************", 0, 5 * (i + 2));
}
//取随机产生的认证码(6个汉字)
//保存生成的汉字字符串
String sRand = "";
for (int i = 0; i < 6; i++) {
int start = random.nextInt(length);
String rand = base.substring(start, start + 1);
sRand += rand;
//设置字体的颜色
g.setColor(getRandColor(random, 10, 150));
//设置字体
g.setFont(new Font(fontTypes[random.nextInt(fontTypesLength)], Font.BOLD, 18 + random.nextInt(6)));
//将此汉字画到图片上
g.drawString(rand, 24 * i + 10 + random.nextInt(8), 24);
}
//将认证码存入session
session.setAttribute("code", sRand);
g.dispose();
//输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
%>
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调用页面：
function fGetCode()
{
document.getElementById('image').src = "apply/image.jsp?rand="+Math.random();
}
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用jsp和servlet生成 图片验证码
login.jsp登录页面
<%@ page contentType="text/html; charset=utf-8"%>
web.xml中的配置
Userservlet.java代码：
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
this.dealwith(request, response);
}
public void dealwith(HttpServletRequest request,
HttpServletResponse response) {
String method = request.getParameter("method");
try {
if (method==null) {
method="login";
}
if ("login".equals(method)) {
this.login(request, response);
}
if("check".equals(method)){
this.checkyzma(request, response);
}
if ("logout".equals(method)) {
this.logout(request,response);
}
if("register".equals(method)){
this.register(request,response);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void login(HttpServletRequest request,HttpServletResponse response) throws Exception{
String username=request.getParameter("username");
String password=request.getParameter("password");
UserDao userdao=new UserDao();
User user=userdao.findUser(username, password);
if (user!=null) {
request.getSession().setAttribute("username", user.getUsername());
request.getSession().setAttribute("logSuccess", "成功登录！");
response.sendRedirect("./admin/contact.do?method=list");
}
//request.getSession().setAttribute("username", "游客");
request.getSession().setAttribute("logfailed", "用户名或密码错误！");
request.getRequestDispatcher("/failed.jsp").forward(request,response);
}
public void checkyzma(HttpServletRequest request,HttpServletResponse response)throws Exception{
String Str1=request.getParameter("yzma");//获取表单上输入的验证码
String sessionStr=(String)request.getSession().getAttribute("yznum");//获取session中的yznum
if(sessionStr!=null && sessionStr.equals(Str1)){
request.getSession().removeAttribute("yznum");
//request.getRequestDispatcher("/success.jsp").forward(request, response);
}
request.getSession().setAttribute("yzmErrMessage", "验证码输入错误");
request.getRequestDispatcher("./login.jsp").forward(request, response);
request.getSession().removeAttribute("yzmErrMessage");
}
MakePic.java代码：
package servlet;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.io.PrintWriter;
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;
import com.sun.java_cup.internal.internal_error;
public class MakePic extends HttpServlet {
/**
* The doGet method of the servlet.
*
* 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 {
this.makeRandPic(request, response);
}
/**
* The doPost method of the servlet.
*
* 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.makeRandPic(request, response);
}
// 给定范围获得随机颜色
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);
}
public void makeRandPic(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();
//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(0,0,0));
//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位数字)
String sRand = "";
for (int i = 0;i < 4; i++) {
String rand = String.valueOf(random.nextInt(10));
sRand += rand;
// 将认证码显示到图象中
// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
g.drawString(rand, 13 * i + 6, 16);
}
// 将认证码存入SESSION
request.getSession().setAttribute("yznum", sRand);
// 图象生效
g.dispose();
// 输出图象到页面
ImageIO.write(image, "JPEG", response.getOutputStream());
}
}