自己封装的一个java图片验证码

验证码生成器：

 package com.lz.Tools;

 import java.awt.Color;
 import java.awt.Font;
 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.image.BufferedImage;
 import java.util.Random;

 /**
  * 验证码生成器
  *
  * @author bojiangzhou
  */
 public class VCodeGenerator {

     /**
      * 验证码来源
      */
     final private char[] code = {
         '2', '3', '4', '5', '6', '7', '8', '9',
         'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j',
         'k', 'm', 'n', 'p', 'q', 'r', 's', 't', 'u', 'v',
         'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F',
         'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'Q', 'R',
         'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z'
     };
     /**
      * 字体
      */
     final private String[] fontNames = new String[]{
             "黑体", "宋体", "Courier", "Arial",
             "Verdana", "Times", "Tahoma", "Georgia"};
     /**
      * 字体样式
      */
     final private int[] fontStyles = new int[]{
             Font.BOLD, Font.ITALIC|Font.BOLD
     };

     /**
      * 验证码长度
      * 默认4个字符
      */
     private int vcodeLen = 4;
     /**
      * 验证码图片字体大小
      * 默认17
      */
     private int fontsize = 21;
     /**
      * 验证码图片宽度
      */
     private int width = (fontsize+1)*vcodeLen+10;
     /**
      * 验证码图片高度
      */
     private int height = fontsize+12;
     /**
      * 干扰线条数
      * 默认3条
      */
     private int disturbline = 3;

     public VCodeGenerator(){}

     /**
      * 指定验证码长度
      * @param vcodeLen 验证码长度
      */
     public VCodeGenerator(int vcodeLen) {
         this.vcodeLen = vcodeLen;
         this.width = (fontsize+1)*vcodeLen+10;
     }

     /**
      * 生成验证码图片
      * @param vcode 要画的验证码
      * @param drawline 是否画干扰线
      * @return
      */
     public BufferedImage generatorVCodeImage(String vcode, boolean drawline){
         //创建验证码图片
         BufferedImage vcodeImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
         Graphics g = vcodeImage.getGraphics();
         //填充背景色
         g.setColor(new Color(246, 240, 250));
         g.fillRect(0, 0, width, height);
         if(drawline){
             drawDisturbLine(g);
         }
         //用于生成伪随机数
         Random ran = new Random();
         //在图片上画验证码
         for(int i = 0;i < vcode.length();i++){
             //设置字体
             g.setFont(new Font(fontNames[ran.nextInt(fontNames.length)], fontStyles[ran.nextInt(fontStyles.length)], fontsize));
             //随机生成颜色
             g.setColor(getRandomColor());
             //画验证码
             g.drawString(vcode.charAt(i)+"", i*fontsize+10, fontsize+5);
         }
         //释放此图形的上下文以及它使用的所有系统资源
         g.dispose();

         return vcodeImage;
     }
     /**
      * 获得旋转字体的验证码图片
      * @param vcode
      * @param drawline 是否画干扰线
      * @return
      */
     public BufferedImage generatorRotateVCodeImage(String vcode, boolean drawline){
         //创建验证码图片
         BufferedImage rotateVcodeImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
         Graphics2D g2d = rotateVcodeImage.createGraphics();
         //填充背景色
         g2d.setColor(new Color(246, 240, 250));
         g2d.fillRect(0, 0, width, height);
         if(drawline){
             drawDisturbLine(g2d);
         }
         //在图片上画验证码
         for(int i = 0;i < vcode.length();i++){
             BufferedImage rotateImage = getRotateImage(vcode.charAt(i));
             g2d.drawImage(rotateImage, null, (int) (this.height * 0.7) * i, 0);
         }
         g2d.dispose();
         return rotateVcodeImage;
     }
     /**
      * 生成验证码
      * @return 验证码
      */
     public String generatorVCode(){
         int len = code.length;
         Random ran = new Random();
         StringBuffer sb = new StringBuffer();
         for(int i = 0;i < vcodeLen;i++){
             int index = ran.nextInt(len);
             sb.append(code[index]);
         }
         return sb.toString();
     }
     /**
      * 为验证码图片画一些干扰线
      * @param g
      */
     private void drawDisturbLine(Graphics g){
         Random ran = new Random();
         for(int i = 0;i < disturbline;i++){
             int x1 = ran.nextInt(width);
             int y1 = ran.nextInt(height);
             int x2 = ran.nextInt(width);
             int y2 = ran.nextInt(height);
             g.setColor(getRandomColor());
             //画干扰线
             g.drawLine(x1, y1, x2, y2);
         }
     }
     /**
      * 获取一张旋转的图片
      * @param c 要画的字符
      * @return
      */
     private BufferedImage getRotateImage(char c){
         BufferedImage rotateImage = new BufferedImage(height, height, BufferedImage.TYPE_INT_ARGB);
         Graphics2D g2d = rotateImage.createGraphics();
         //设置透明度为0
         g2d.setColor(new Color(255, 255, 255, 0));
         g2d.fillRect(0, 0, height, height);
         Random ran = new Random();
         g2d.setFont(new Font(fontNames[ran.nextInt(fontNames.length)], fontStyles[ran.nextInt(fontStyles.length)], fontsize));
         g2d.setColor(getRandomColor());
         double theta = getTheta();
         //旋转图片
         g2d.rotate(theta, height/2, height/2);
         g2d.drawString(Character.toString(c), (height-fontsize)/2, fontsize+5);
         g2d.dispose();

         return rotateImage;
     }
     /**
      * @return 返回一个随机颜色
      */
     private Color getRandomColor(){
         Random ran = new Random();
         return new Color(ran.nextInt(220), ran.nextInt(220), ran.nextInt(220));
     }
     /**
      * @return 角度
      */
     private double getTheta(){
         return ((int) (Math.random()*1000) % 2 == 0 ? -1 : 1)*Math.random();
     }

     /**
      * @return 验证码字符个数
      */
     public int getVcodeLen() {
         return vcodeLen;
     }
     /**
      * 设置验证码字符个数
      * @param vcodeLen
      */
     public void setVcodeLen(int vcodeLen) {
         this.width = (fontsize+3)*vcodeLen+10;
         this.vcodeLen = vcodeLen;
     }
     /**
      * @return 字体大小
      */
     public int getFontsize() {
         return fontsize;
     }
     /**
      * 设置字体大小
      * @param fontsize
      */
     public void setFontsize(int fontsize) {
         this.width = (fontsize+3)*vcodeLen+10;
         this.height = fontsize+15;
         this.fontsize = fontsize;
     }
     /**
      * @return 图片宽度
      */
     public int getWidth() {
         return width;
     }
     /**
      * 设置图片宽度
      * @param width
      */
     public void setWidth(int width) {
         this.width = width;
     }
     /**
      * @return 图片高度
      */
     public int getHeight() {
         return height;
     }
     /**
      * 设置图片高度
      * @param height
      */
     public void setHeight(int height) {
         this.height = height;
     }
     /**
      * @return 干扰线条数
      */
     public int getDisturbline() {
         return disturbline;
     }
     /**
      * 设置干扰线条数
      * @param disturbline
      */
     public void setDisturbline(int disturbline) {
         this.disturbline = disturbline;
     }

 }

在servlet里获取验证码

 package com.lz.Servlet;

 import java.awt.image.BufferedImage;
 import java.io.IOException;

 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.lz.Tools.VCodeGenerator;

 /**
  * 获取验证码
  * @author bojiangzhou
  *
  */
 public class GetVCodeServlet extends HttpServlet {

     private static final long serialVersionUID = 3259532010990625726L;

     public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
         //验证码不能缓存
         response.setHeader("Expires", "-1");
         response.setHeader("cache-control", "no-cahce");
         response.setHeader("pragma", "no-cache");

         VCodeGenerator vcg = new VCodeGenerator();
         //取得验证码
         String vcode = vcg.generatorVCode();
         //获取验证码图片
 //        BufferedImage vcodeImage = vcg.generatorRotateVCodeImage(vcode, true);
         BufferedImage vcodeImage = vcg.generatorVCodeImage(vcode, true);
         //将验证码保存到session域对象
         request.getSession().setAttribute("vcode", vcode);
         //输出验证码图片
         ImageIO.write(vcodeImage, "gif", response.getOutputStream());
     }

 }

前台在img标签里用src获取验证码图片即可

<img class="vcode" src="GetVCodeServlet" />

OK!!!

下载源文件