生成验证码效果

生成验证码效果

 

 

 

 

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>