【java】注册功能动态验证码的生成和验证（完整图片验证码封装工具类）

1、验证码工具类

package com.imopan.cps.gfanpaly.util;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Arrays;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;

public class VerifyCodeUtil {

//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，去掉了1,0,i,o几个容易混淆的字符
public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
private static Random random = new Random();

/**
* 使用系统默认字符源生成验证码
* @param verifySize    验证码长度
* @return
*/
public static String generateVerifyCode(int verifySize){
return generateVerifyCode(verifySize, VERIFY_CODES);
}
/**
* 使用指定源生成验证码
* @param verifySize    验证码长度
* @param sources   验证码字符源
* @return
*/
public static String generateVerifyCode(int verifySize, String sources){
if(sources == null || sources.length() == 0){
sources = VERIFY_CODES;
}
int codesLen = sources.length();
Random rand = new Random(System.currentTimeMillis());
StringBuilder verifyCode = new StringBuilder(verifySize);
for(int i = 0; i < verifySize; i++){
verifyCode.append(sources.charAt(rand.nextInt(codesLen-1)));
}
return verifyCode.toString();
}

/**
* 生成随机验证码文件,并返回验证码值
* @param w
* @param h
* @param outputFile
* @param verifySize
* @return
* @throws IOException
*/
public static String outputVerifyImage(int w, int h, File outputFile, int verifySize) throws IOException{
String verifyCode = generateVerifyCode(verifySize);
outputImage(w, h, outputFile, verifyCode);
return verifyCode;
}

/**
* 输出随机验证码图片流,并返回验证码值
* @param w
* @param h
* @param os
* @param verifySize
* @return
* @throws IOException
*/
public static String outputVerifyImage(int w, int h, OutputStream os, int verifySize) throws IOException{
String verifyCode = generateVerifyCode(verifySize);
outputImage(w, h, os, verifyCode);
return verifyCode;
}

/**
* 生成指定验证码图像文件
* @param w
* @param h
* @param outputFile
* @param code
* @throws IOException
*/
public static void outputImage(int w, int h, File outputFile, String code) throws IOException{
if(outputFile == null){
return;
}
File dir = outputFile.getParentFile();
if(!dir.exists()){
dir.mkdirs();
}
try{
outputFile.createNewFile();
FileOutputStream fos = new FileOutputStream(outputFile);
outputImage(w, h, fos, code);
fos.close();
} catch(IOException e){
throw e;
}
}

/**
* 输出指定验证码图片流
* @param w
* @param h
* @param os
* @param code
* @throws IOException
*/
public static void outputImage(int w, int h, OutputStream os, String code) throws IOException{
int verifySize = code.length();
BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Random rand = new Random();
Graphics2D g2 = image.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
Color[] colors = new Color[5];
Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,
Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE,
Color.PINK, Color.YELLOW };
float[] fractions = new float[colors.length];
for(int i = 0; i < colors.length; i++){
colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
fractions[i] = rand.nextFloat();
}
Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色
g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);
g2.setColor(c);// 设置背景色
g2.fillRect(0, 2, w, h-4);

//绘制干扰线
Random random = new Random();
g2.setColor(getRandColor(160, 200));// 设置线条的颜色
for (int i = 0; i < 20; i++) {
int x = random.nextInt(w - 1);
int y = random.nextInt(h - 1);
int xl = random.nextInt(6) + 1;
int yl = random.nextInt(12) + 1;
g2.drawLine(x, y, x + xl + 40, y + yl + 20);
}

// 添加噪点
float yawpRate = 0.05f;// 噪声率
int area = (int) (yawpRate * w * h);
for (int i = 0; i < area; i++) {
int x = random.nextInt(w);
int y = random.nextInt(h);
int rgb = getRandomIntColor();
image.setRGB(x, y, rgb);
}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));
int fontSize = h-4;
Font font = new Font("Algerian", Font.ITALIC, fontSize);
g2.setFont(font);
char[] chars = code.toCharArray();
for(int i = 0; i < verifySize; i++){
AffineTransform affine = new AffineTransform();
affine.setToRotation(Math.PI / 4 * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2, h/2);
g2.setTransform(affine);
g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5, h/2 + fontSize/2 - 10);
}

g2.dispose();
ImageIO.write(image, "jpg", os);
}

/**
* 输出指定验证码图片流
* @param w
* @param h
* @param os
* @param code
* @param resp
* @throws IOException
*/
public static void outputImage(int w, int h, OutputStream os, String code, HttpServletResponse response) throws IOException{
int verifySize = code.length();
BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Random rand = new Random();
Graphics2D g2 = image.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
Color[] colors = new Color[5];
Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,
Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE,
Color.PINK, Color.YELLOW };
float[] fractions = new float[colors.length];
for(int i = 0; i < colors.length; i++){
colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
fractions[i] = rand.nextFloat();
}
Arrays.sort(fractions);

g2.setColor(Color.GRAY);// 设置边框色
g2.fillRect(0, 0, w, h);

Color c = getRandColor(200, 250);
g2.setColor(c);// 设置背景色
g2.fillRect(0, 2, w, h-4);

//绘制干扰线
Random random = new Random();
g2.setColor(getRandColor(160, 200));// 设置线条的颜色
for (int i = 0; i < 20; i++) {
int x = random.nextInt(w - 1);
int y = random.nextInt(h - 1);
int xl = random.nextInt(6) + 1;
int yl = random.nextInt(12) + 1;
g2.drawLine(x, y, x + xl + 40, y + yl + 20);
}

// 添加噪点
float yawpRate = 0.05f;// 噪声率
int area = (int) (yawpRate * w * h);
for (int i = 0; i < area; i++) {
int x = random.nextInt(w);
int y = random.nextInt(h);
int rgb = getRandomIntColor();
image.setRGB(x, y, rgb);
}

shear(g2, w, h, c);// 使图片扭曲

g2.setColor(getRandColor(100, 160));
int fontSize = h-4;
Font font = new Font("Algerian", Font.ITALIC, fontSize);
g2.setFont(font);
char[] chars = code.toCharArray();
for(int i = 0; i < verifySize; i++){
AffineTransform affine = new AffineTransform();
affine.setToRotation(Math.PI / 4 * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2, h/2);
g2.setTransform(affine);
g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5, h/2 + fontSize/2 - 10);
}

g2.dispose();
ImageIO.write(image, "jpg", os);
}

private static Color getRandColor(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);
}

private static int getRandomIntColor() {
int[] rgb = getRandomRgb();
int color = 0;
for (int c : rgb) {
color = color << 8;
color = color | c;
}
return color;
}

private static int[] getRandomRgb() {
int[] rgb = new int[3];
for (int i = 0; i < 3; i++) {
rgb[i] = random.nextInt(255);
}
return rgb;
}

private static void shear(Graphics g, int w1, int h1, Color color) {
shearX(g, w1, h1, color);
shearY(g, w1, h1, color);
}

private static void shearX(Graphics g, int w1, int h1, Color color) {

int period = random.nextInt(2);

boolean borderGap = true;
int frames = 1;
int phase = random.nextInt(2);

for (int i = 0; i < h1; i++) {
double d = (double) (period >> 1)
* Math.sin((double) i / (double) period
+ (6.2831853071795862D * (double) phase)
/ (double) frames);
g.copyArea(0, i, w1, 1, (int) d, 0);
if (borderGap) {
g.setColor(color);
g.drawLine((int) d, i, 0, i);
g.drawLine((int) d + w1, i, w1, i);
}
}

}

private static void shearY(Graphics g, int w1, int h1, Color color) {

int period = random.nextInt(40) + 10; // 50;

boolean borderGap = true;
int frames = 20;
int phase = 7;
for (int i = 0; i < w1; i++) {
double d = (double) (period >> 1)
* Math.sin((double) i / (double) period
+ (6.2831853071795862D * (double) phase)
/ (double) frames);
g.copyArea(i, 0, 1, h1, 0, (int) d);
if (borderGap) {
g.setColor(color);
g.drawLine(i, (int) d, i, 0);
g.drawLine(i, (int) d + h1, i, h1);
}

}

}
public static void main(String[] args) throws IOException{
File dir = new File("F:");
int w = 200, h = 80;
for(int i = 0; i < 50; i++){
String verifyCode = generateVerifyCode(4);
File file = new File(dir, verifyCode + ".jpg");
outputImage(w, h, file, verifyCode);
}
}
}

2、调用

public void getCode(HttpServletRequest req, HttpServletResponse resp) throws IOException {
resp.setHeader("Pragma", "No-cache");
resp.setHeader("Cache-Control", "no-cache");
resp.setDateHeader("Expires", 0);
resp.setContentType("image/jpeg");

//生成随机字串
String verifyCode = VerifyCodeUtil.generateVerifyCode(4);
//存入会话session
HttpSession session = req.getSession(true);
session.setAttribute("login_verify_code", verifyCode.toLowerCase());
//生成图片
int w = 75, h = 36;
VerifyCodeUtil.outputImage(w, h, resp.getOutputStream(), verifyCode, resp);
}

3、场景应用

1、struts2应用

action

package com.zhuguang.action;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.interceptor.ServletResponseAware;
import org.apache.struts2.interceptor.SessionAware;

import com.opensymphony.xwork2.ActionSupport;

public class TestAction extends ActionSupport implements SessionAware,
        ServletResponseAware {
    private Map<String, Object> session;
    private HttpServletResponse response;
    private static final long serialVersionUID = 1L;
    private String chknumber;

    @Override
    public String execute() throws Exception {
        //请求头可不设置
        response.setHeader("Cache-Control", "no-cache");
        // 生成随机字串
        String verifyCode = VerifyCodeUtil.generateVerifyCode(4);
        session.put("randomCode", verifyCode);     //写入session中  
        // 生成图片
        int w = 100, h = 50;
        VerifyCodeUtil.outputImage(w, h, response.getOutputStream(),
                verifyCode, response);
        return null;
    }

    public String getChknumber() {
        return chknumber;
    }

    public void setChknumber(String chknumber) {
        this.chknumber = chknumber;
    }

    @Override
    public void setSession(Map<String, Object> session) {
        // TODO Auto-generated method stub
        this.session = session;
    }

    @Override
    public void setServletResponse(HttpServletResponse response) {
        // TODO Auto-generated method stub
        this.response = response;
    }

}

struts.xml

<action name="randomCode" class="com.zhuguang.action.TestAction">
</action>

jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib uri="/struts-tags" prefix="s" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<script type="text/javascript">
<!--
function reloadcode(obj,base){
var rand=new Date().getTime(); //这里用当前时间作为参数加到url中，是为了使URL发生变化，这样验证码才会动态加载，
//只是一个干扰作用，无确实意义，但却又非常巧妙，呵呵
obj.src=base+"randomCode.action?abc="+rand; //其实服务器端是没有abc的字段的。
}
//-->
</script>
<title>测试页面</title>
</head>
<body>
<form action="testLogin" method="post">
Username<input type="text" name="name"><br>
Password<input type="text" name="password"><br>
验证码：<input type="text" name="chknumber" id="chknumber" maxlength="4" class="chknumber_input">
<img title="看不清楚请点击这里" width="50" height="20" src="<%=basePath%>randomCode.action" id="safecode" onclick="reloadcode(this,'<%=basePath%>')" /><br>
<input type="submit" value="Loginin">
</form>
</body>
</html>

对比

public String testLogin()
{
if(session.get("randomCode").equals(chknumber))
{
return SUCCESS;
}
else
{
return ERROR;
}
}