验证码

package com.haier.cosmoplat.portal.util;  
  
import java.awt.Color;  
import java.awt.Font;  
import java.awt.Graphics2D;  
import java.awt.image.BufferedImage;  
import java.io.FileNotFoundException;  
import java.io.FileOutputStream;  
import java.io.IOException;  
import java.io.OutputStream;  
import java.util.Random;  
import javax.imageio.ImageIO;  
  
/** 
 * 验证码生成类 
 */  
public class RandomImageGenerator {  
      
    // 创建Random对象  
    static Random random = new Random();  
  
    // 随机生成包含验证码字符串  
    public static String random(int num) {  
        // 初始化种子  
        String[] str = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b", "c", "d", "e", "f", "g", "h", "i",  
                "j", "k", "l", "m", "n", "p", "q", "r", "s", "t" };  
        int number = str.length;  
        // 接收随机字符  
        String text = "";  
        // 随机产生4个字符的字符串  
        for (int i = 0; i < num; i++) {  
            text += str[random.nextInt(number)];  
        }  
        return text;  
    }  
  
    /** 
     * 随机产生定义的颜色 
     * @return 
     */  
    private static Color getRandColor() {  
        Random random = new Random();  
        Color color[] = new Color[10];  
        color[0] = new Color(32, 158, 25);  
        color[1] = new Color(218, 42, 19);  
        color[2] = new Color(31, 75, 208);  
        color[3] = new Color(0, 102, 182);  
        color[4] = new Color(171, 0, 85);  
        return color[random.nextInt(5)];  
    }  
  
    /** 
     * 产生随机字体 
     * @return 
     */  
    private static Font getFont() {  
        Random random = new Random();  
        Font font[] = new Font[5];  
        font[0] = new Font("Ravie", Font.BOLD, 30);  
        font[1] = new Font("Antique Olive Compact", Font.BOLD, 30);  
        font[2] = new Font("Forte", Font.BOLD, 30);  
        font[3] = new Font("Wide Latin", Font.BOLD, 30);  
        font[4] = new Font("Gill Sans Ultra Bold", Font.BOLD, 30);  
        return font[random.nextInt(5)];  
    }  
  
    /** 
     * 生成图片 
     * @throws IOException 
     */  
    public static void render(String randomStr, OutputStream out, int width, int height) throws IOException {  
        // 在内存中创建图像  
        BufferedImage bi = new BufferedImage(width, height, BufferedImage.TYPE_BYTE_INDEXED);  
        // 获取图形上下文  
        Graphics2D g = (Graphics2D) bi.getGraphics();  
        // 话边框  
        g.setColor(Color.white);  
        g.fillRect(0, 0, width, height);  
        g.setFont(getFont());  
        g.setColor(Color.BLACK);  
        // 画认证码，每个认证码在不同的水平位置  
        String str1[] = new String[randomStr.length()];  
        for (int i = 0; i < str1.length; i++) {  
            str1[i] = randomStr.substring(i, i + 1);  
            int w = 0;  
            int x = (i + 1) % 3;  
            // 随机生成验证码字符水平偏移量  
            if (x == random.nextInt(7)) {  
                w = 30 - random.nextInt(7);  
            } else {  
                w = 30 + random.nextInt(7);  
            }  
            // 随机生成颜色  
            g.setColor(getRandColor());  
            g.drawString(str1[i], 20 * i + 10, w);  
        }  
        // 随机产生干扰点，并用不同的颜色表示，事图像的认证码不易被其他程序探测到  
        for (int i = 0; i < 100; i++) {  
            int x = random.nextInt(width);  
            int y = random.nextInt(height);  
            Color color = new Color(random.nextInt(255), random.nextInt(255), random.nextInt(255));  
            // 随机画各种颜色的线  
            g.setColor(color);  
            g.drawOval(x, y, 0, 0);  
        }  
        // 画干扰线  
        for (int i = 0; i < 15; i++) {  
            int x = random.nextInt(width);  
            int y = random.nextInt(height);  
            int x1 = random.nextInt(width);  
            int y1 = random.nextInt(height);  
            Color color = new Color(random.nextInt(255), random.nextInt(255), random.nextInt(255));  
            // 随机画各种颜色线  
            g.setColor(color);  
            g.drawLine(x, y, x1, y1);  
        }  
        // 图像生效  
        g.dispose();  
        // 输出页面  
        ImageIO.write(bi, "jpg", out);  
    }  
  
    public static void main(String[] args) throws FileNotFoundException, IOException {  
        // 获取随机字符串  
        String randomStr = random(5);  
        System.out.println(randomStr);  
        // 生成图片  
        render(randomStr, new FileOutputStream("D:\\test.jpg"), 130, 40);  
    }  
} 

　　调用方法：

@ApiOperation("code")  
@RequestMapping(value = "/code", method = RequestMethod.GET)  
public void code(HttpServletResponse response, String randomStr) throws FileNotFoundException, IOException {  
    // String randomStr = RandomImageGenerator.random(4);//生成4位随机数  
        //<span style="line-height: 1.5;">randomStr 验证码  
</span>        //110：宽度，40：高度  
    RandomImageGenerator.render(randomStr, response.getOutputStream(), 110, 40);  
}