简单的图片验证码

package com.fh.controller.system.secCode;import java.awt.Color;import java.awt.Font;import java.awt.Graphics2D;import java.awt.font.FontRenderContext;import java.awt.geom.Rectangle2D;import java.awt.image.BufferedImage;import java.io.ByteArrayOutputStream;import java.io.IOException;import java.util.Random;import javax.imageio.ImageIO;import javax.servlet.ServletOutputStream;import javax.servlet.http.HttpServletResponse;import org.apache.shiro.SecurityUtils;import org.apache.shiro.session.Session;import org.apache.shiro.subject.Subject;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import com.fh.util.Const;/**  * 类名称：SecCodeController * 类描述：  * 作者单位：  * 联系方式： * @version */@Controller@RequestMapping("/code")public class SecCodeController {@RequestMappingpublic void generate(HttpServletResponse response){ByteArrayOutputStream output = new ByteArrayOutputStream();String code = drawImg(output);Subject currentUser = SecurityUtils.getSubject();  Session session = currentUser.getSession();session.setAttribute(Const.SESSION_SECURITY_CODE, code);try {ServletOutputStream out = response.getOutputStream();output.writeTo(out);} catch (IOException e) {e.printStackTrace();}}private String drawImg(ByteArrayOutputStream output){String code = "";for(int i=0; i<4; i++){code += randomChar();}int width = 70;int height = 25;BufferedImage bi = new BufferedImage(width,height,BufferedImage.TYPE_3BYTE_BGR);Font font = new Font("Times New Roman",Font.PLAIN,20);Graphics2D g = bi.createGraphics();g.setFont(font);Color color = new Color(66,2,82);g.setColor(color);g.setBackground(new Color(226,226,240));g.clearRect(0, 0, width, height);FontRenderContext context = g.getFontRenderContext();Rectangle2D bounds = font.getStringBounds(code, context);double x = (width - bounds.getWidth()) / 2;double y = (height - bounds.getHeight()) / 2;double ascent = bounds.getY();double baseY = y - ascent;g.drawString(code, (int)x, (int)baseY);g.dispose();try {ImageIO.write(bi, "jpg", output);} catch (IOException e) {e.printStackTrace();}return code;}private char randomChar(){Random r = new Random();String s = "ABCDEFGHJKLMNPRSTUVWXYZ0123456789";return s.charAt(r.nextInt(s.length()));}}

来一个稍微复杂的

package util.verify;import java.awt.Color;import java.awt.Font;import java.awt.Graphics;import java.awt.image.BufferedImage;import java.util.Random;/** * 验证码生成器类，可生成数字、大写、小写字母及三者混合类型的验证码。 * 支持自定义验证码字符数量； * 支持自定义验证码图片的大小； * 支持自定义需排除的特殊字符； * 支持自定义干扰线的数量； * 支持自定义验证码图文颜色 * @author org.javachina * @version 1.01 */public class VerifyCode {//验证码类型，评论public static final String VERIFY_TYPE_COMMENT="VERIFY_TYPE_COMMENT";/** * 验证码类型为仅数字 0~9 */public static final int TYPE_NUM_ONLY=0;/** * 验证码类型为仅字母，即大写、小写字母混合 */public static final int TYPE_LETTER_ONLY=1;/** * 验证码类型为数字、大写字母、小写字母混合 */public static final int TYPE_ALL_MIXED=2;/** * 验证码类型为数字、大写字母混合 */public static final int TYPE_NUM_UPPER=3;/** * 验证码类型为数字、小写字母混合 */public static final int TYPE_NUM_LOWER=4;/** * 验证码类型为仅大写字母 */public static final int TYPE_UPPER_ONLY=5;/** * 验证码类型为仅小写字母 */public static final int TYPE_LOWER_ONLY=6;private VerifyCode(){}/** * 生成验证码字符串 * @param type 验证码类型，参见本类的静态属性 * @param length 验证码长度，大于0的整数 * @param exChars 需排除的特殊字符（仅对数字、字母混合型验证码有效，无需排除则为null） * @return 验证码字符串 */public static String generateTextCode(int type,int length,String exChars){if(length<=0) return "";StringBuffer code=new StringBuffer();int i=0;Random r=new Random();switch(type){//仅数字case TYPE_NUM_ONLY:while(i<length){            int t=r.nextInt(10);if(exChars==null||exChars.indexOf(t+"")<0){//排除特殊字符code.append(t);i++;}}break;    //仅字母（即大写字母、小写字母混合）case TYPE_LETTER_ONLY:while(i<length){int t=r.nextInt(123);if((t>=97||(t>=65&&t<=90))&&(exChars==null||exChars.indexOf((char)t)<0)){code.append((char)t);i++;}}break;//数字、大写字母、小写字母混合case TYPE_ALL_MIXED:while(i<length){int t=r.nextInt(123);if((t>=97||(t>=65&&t<=90)||(t>=48&&t<=57))&&(exChars==null||exChars.indexOf((char)t)<0)){code.append((char)t);i++;}}break;//数字、大写字母混合case TYPE_NUM_UPPER:while(i<length){int t=r.nextInt(91);if((t>=65||(t>=48&&t<=57))&&(exChars==null||exChars.indexOf((char)t)<0)){code.append((char)t);i++;}}break;//数字、小写字母混合case TYPE_NUM_LOWER:while(i<length){int t=r.nextInt(123);if((t>=97||(t>=48&&t<=57))&&(exChars==null||exChars.indexOf((char)t)<0)){code.append((char)t);i++;}}break;//仅大写字母case TYPE_UPPER_ONLY:while(i<length){int t=r.nextInt(91);if((t>=65)&&(exChars==null||exChars.indexOf((char)t)<0)){code.append((char)t);i++;}}break;//仅小写字母case TYPE_LOWER_ONLY:while(i<length){int t=r.nextInt(123);if((t>=97)&&(exChars==null||exChars.indexOf((char)t)<0)){code.append((char)t);i++;}}break;}return code.toString();}/** * 已有验证码，生成验证码图片 * @param textCode 文本验证码 * @param width 图片宽度 * @param height 图片高度 * @param interLine 图片中干扰线的条数 * @param randomLocation 每个字符的高低位置是否随机 * @param backColor 图片颜色，若为null，则采用随机颜色 * @param foreColor 字体颜色，若为null，则采用随机颜色 * @param lineColor 干扰线颜色，若为null，则采用随机颜色 * @return 图片缓存对象 */public static BufferedImage generateImageCode(String textCode,int width,int height,int interLine,boolean randomLocation,Color backColor,Color foreColor,Color lineColor){BufferedImage bim=new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);Graphics g=bim.getGraphics();//画背景图g.setColor(backColor==null?getRandomColor():backColor);g.fillRect(0,0,width,height);//画干扰线Random r=new Random();if(interLine>0){int x=0,y=0,x1=width,y1=0;for(int i=0;i<interLine;i++){g.setColor(lineColor==null?getRandomColor():lineColor);y=r.nextInt(height);y1=r.nextInt(height);g.drawLine(x,y,x1,y1);}}//写验证码//g.setColor(getRandomColor());//g.setColor(isSimpleColor?Color.BLACK:Color.WHITE);//字体大小为图片高度的80%int fsize=(int)(height*0.8);int fx=height-fsize;int fy=fsize;g.setFont(new Font("Times New Roman", Font.BOLD, 20));//写验证码字符for(int i=0;i<textCode.length();i++){fy=randomLocation?(int)((Math.random()*0.3+0.6)*height):fy;//每个字符高低是否随机g.setColor(foreColor==null?getRandomColor():foreColor);g.drawString(textCode.charAt(i)+"",fx,fy);fx+=fsize*0.9;}g.dispose();return bim;}/** * 生成图片验证码 * @param type 验证码类型，参见本类的静态属性 * @param length 验证码字符长度，大于0的整数 * @param exChars 需排除的特殊字符 * @param width 图片宽度 * @param height 图片高度 * @param interLine 图片中干扰线的条数 * @param randomLocation 每个字符的高低位置是否随机 * @param backColor 图片颜色，若为null，则采用随机颜色 * @param foreColor 字体颜色，若为null，则采用随机颜色 * @param lineColor 干扰线颜色，若为null，则采用随机颜色 * @return 图片缓存对象 */public static BufferedImage generateImageCode(int type,int length,String exChars,int width,int height,int interLine,boolean randomLocation,Color backColor,Color foreColor,Color lineColor){String textCode=generateTextCode(type,length,exChars);BufferedImage bim=generateImageCode(textCode,width,height,interLine,randomLocation,backColor,foreColor,lineColor);return bim;}/** * 产生随机颜色 * @return */private static Color getRandomColor(){Random r=new Random();Color c=new Color(r.nextInt(255),r.nextInt(255),r.nextInt(255));return c;}public static void main(String[] args){}}

        //设置浏览器不缓存本页// Set to expire far in the past.           response.setDateHeader("Expires", 0);           // Set standard HTTP/1.1 no-cache headers.           response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");           // Set IE extended HTTP/1.1 no-cache headers (use addHeader).           response.addHeader("Cache-Control", "post-check=0, pre-check=0");           // Set standard HTTP/1.0 no-cache header.           response.setHeader("Pragma", "no-cache");   //生成验证码，写入用户sessionString verifyCode=VerifyCode.generateTextCode(VerifyCode.TYPE_NUM_UPPER,4,"0oOilJI1");request.getSession().setAttribute(VerifyCode.VERIFY_TYPE_COMMENT,verifyCode);System.out.println("verifyCode="+verifyCode);//输出验证码给客户端response.setContentType("image/jpeg");/*    textCode 文本验证码width 图片宽度height 图片高度interLine 图片中干扰线的条数randomLocation 每个字符的高低位置是否随机backColor 图片颜色，若为null，则采用随机颜色foreColor 字体颜色，若为null，则采用随机颜色lineColor 干扰线颜色，若为null，则采用随机颜色*/BufferedImage bim=VerifyCode.generateImageCode(verifyCode, 70, 22, 15,true,Color.WHITE,Color.BLACK,null);ServletOutputStream out=response.getOutputStream();ImageIO.write(bim, "JPEG",out);try{out.flush();}finally{out.close();}