图形验证码生成工具类

 

ValidateCode.java 验证码生成类

 

package cn.dsna.util.images;  
  
import java.awt.Color;  
import java.awt.Font;  
import java.awt.Graphics2D;  
import java.awt.image.BufferedImage;  
import java.io.FileOutputStream;  
import java.io.IOException;  
import java.io.OutputStream;  
import java.util.Random;  
  
import javax.imageio.ImageIO;  
/** 
 * 验证码生成器 
 * @author dsna 
 * 
 */  
public class ValidateCode {  
    // 图片的宽度。  
    private int width = 160;  
    // 图片的高度。  
    private int height = 40;  
    // 验证码字符个数  
    private int codeCount = 5;  
    // 验证码干扰线数  
    private int lineCount = 150;  
    // 验证码  
    private String code = null;  
    // 验证码图片Buffer  
    private BufferedImage buffImg=null;  
  
    private char[] codeSequence = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',  
            'K', 'L', 'M', 'N',  'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W',  
            'X', 'Y', 'Z',  '1', '2', '3', '4', '5', '6', '7', '8', '9' };  
  
    public  ValidateCode() {  
        this.createCode();  
    }  
  
    /** 
     *  
     * @param width 图片宽 
     * @param height 图片高 
     */  
    public  ValidateCode(int width,int height) {  
        this.width=width;  
        this.height=height;  
        this.createCode();  
    }  
    /** 
     *  
     * @param width 图片宽 
     * @param height 图片高 
     * @param codeCount 字符个数 
     * @param lineCount 干扰线条数 
     */  
    public  ValidateCode(int width,int height,int codeCount,int lineCount) {  
        this.width=width;  
        this.height=height;  
        this.codeCount=codeCount;  
        this.lineCount=lineCount;  
        this.createCode();  
    }  
      
    public void createCode() {  
        int x = 0,fontHeight=0,codeY=0;  
        int red = 0, green = 0, blue = 0;  
          
        x = width / (codeCount +2);//每个字符的宽度  
        fontHeight = height - 2;//字体的高度  
        codeY = height - 4;  
          
        // 图像buffer  
        buffImg = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);  
        Graphics2D g = buffImg.createGraphics();  
        // 生成随机数  
        Random random = new Random();  
        // 将图像填充为白色  
        g.setColor(Color.WHITE);  
        g.fillRect(0, 0, width, height);  
        // 创建字体  
        ImgFontByte imgFont=new ImgFontByte();  
        Font font =imgFont.getFont(fontHeight);  
        g.setFont(font);  
          
        for (int i = 0; i < lineCount; i++) {  
            int xs = random.nextInt(width);  
            int ys = random.nextInt(height);  
            int xe = xs+random.nextInt(width/8);  
            int ye = ys+random.nextInt(height/8);  
            red = random.nextInt(255);  
            green = random.nextInt(255);  
            blue = random.nextInt(255);  
            g.setColor(new Color(red, green, blue));  
            g.drawLine(xs, ys, xe, ye);  
        }  
          
        // randomCode记录随机产生的验证码  
        StringBuffer randomCode = new StringBuffer();  
        // 随机产生codeCount个字符的验证码。  
        for (int i = 0; i < codeCount; i++) {  
            String strRand = String.valueOf(codeSequence[random.nextInt(codeSequence.length)]);  
            // 产生随机的颜色值，让输出的每个字符的颜色值都将不同。  
            red = random.nextInt(255);  
            green = random.nextInt(255);  
            blue = random.nextInt(255);  
            g.setColor(new Color(red, green, blue));  
            g.drawString(strRand, (i + 1) * x, codeY);  
            // 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。  
        code=randomCode.toString();       
    }  
      
    public void write(String path) throws IOException {  
        OutputStream sos = new FileOutputStream(path);  
            this.write(sos);  
    }  
      
    public void write(OutputStream sos) throws IOException {  
            ImageIO.write(buffImg, "png", sos);  
            sos.close();  
    }  
    public BufferedImage getBuffImg() {  
        return buffImg;  
    }  
      
    public String getCode() {  
        return code;  
    }  
} 

 

ImgFontByte.java

 

package cn.dsna.util.images;  
import java.io.ByteArrayInputStream;  
import java.awt.*;  
/** 
 * ttf字体文件 
 * @author dsna 
 * 
 */  
public class ImgFontByte {  
    public Font getFont(int fontHeight){  
        try {  
            Font baseFont = Font.createFont(Font.TRUETYPE_FONT, new ByteArrayInputStream(hex2byte(getFontByteStr())));  
            return baseFont.deriveFont(Font.PLAIN, fontHeight);  
        } catch (Exception e) {  
            return new Font("Arial",Font.PLAIN, fontHeight);  
        }  
    }  
      
    private  byte[] hex2byte(String str) {   
        if (str == null)  
            return null;  
        str = str.trim();  
        int len = str.length();  
        if (len == 0 || len % 2 == 1)  
            return null;  
  
        byte[] b = new byte[len / 2];  
        try {  
            for (int i = 0; i < str.length(); i += 2) {  
                b[i / 2] = (byte) Integer  
                        .decode("0x" + str.substring(i, i + 2)).intValue();  
            }  
            return b;  
        } catch (Exception e) {  
            return null;  
        }  
    } /** 
  * ttf字体文件的十六进制字符串 
  * @return 
  */  
 private String getFontByteStr(){ return null;  
        return str;//字符串太长 在附件中找  
}  
} 

 

ValidateCodeServlet.java Servlet调用方法

 

package cn.dsna.util.images;  
  
import java.io.IOException;  
import javax.servlet.ServletException;  
import javax.servlet.http.HttpServlet;  
import javax.servlet.http.HttpServletRequest;  
import javax.servlet.http.HttpServletResponse;  
import javax.servlet.http.HttpSession;  
  
public class ValidateCodeServlet extends HttpServlet {  
    private static final long serialVersionUID = 1L;  
  
    @Override  
    protected void doGet(HttpServletRequest reqeust,  
            HttpServletResponse response) throws ServletException, IOException {  
        // 设置响应的类型格式为图片格式  
        response.setContentType("image/jpeg");  
        //禁止图像缓存。  
        response.setHeader("Pragma", "no-cache");  
        response.setHeader("Cache-Control", "no-cache");  
        response.setDateHeader("Expires", 0);  
          
        HttpSession session = reqeust.getSession();  
          
        ValidateCode vCode = new ValidateCode(120,40,5,100);  
        session.setAttribute("code", vCode.getCode());  
        vCode.write(response.getOutputStream());  
    }  
/** 
 * web.xml 添加servlet 
    <servlet> 
        <servlet-name>validateCodeServlet</servlet-name> 
        <servlet-class>cn.dsna.util.images.ValidateCodeServlet</servlet-class> 
    </servlet>     
    <servlet-mapping> 
        <servlet-name>validateCodeServlet</servlet-name> 
        <url-pattern>*.images</url-pattern> 
    </servlet-mapping> 
 
在地址栏输入XXX/dsna.images 测试 
 */  
  
}  

 

测试类

ValidateCodeTest.java

 

package cn.dsna.util.images;  
  
import java.io.IOException;  
import java.util.Date;  
  
public class ValidateCodeTest {  
  
    /** 
     * @param args 
     */  
    public static void main(String[] args) {  
        ValidateCode vCode = new ValidateCode(120,40,5,100);  
        try {  
            String path="D:/t/"+new Date().getTime()+".png";  
            System.out.println(vCode.getCode()+" >"+path);  
            vCode.write(path);  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }  
  
}  

 

web.xml 配置

 

<servlet>  
    <servlet-name>validateCodeServlet</servlet-name>  
    <servlet-class>cn.dsna.util.images.ValidateCodeServlet</servlet-class>  
</servlet>      
<servlet-mapping>  
    <servlet-name>validateCodeServlet</servlet-name>  
    <url-pattern>*.images</url-pattern>  
</servlet-mapping>