生成驗證碼的java代碼

生成驗證碼的java代碼

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

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.shiro.SecurityUtils;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

@Controller
public class Pic {
	
	private final Font mFont =
			new Font("Arial Black", Font.PLAIN, 16);
		private final int IMG_WIDTH = 100;
		private final int IMG_HEIGTH = 18;
		private Color getRandColor(int fc,int bc)
		{
			Random random = new Random();
			if(fc > 255) fc = 255;
			if(bc > 255) bc=255;
			int r = fc + random.nextInt(bc - fc);
			int g = fc + random.nextInt(bc - fc);
			int b = fc + random.nextInt(bc - fc);
			return new Color(r , g , b);
		}
@ResponseBody	
@RequestMapping(value="/authImg",method={RequestMethod.GET})
public void getpic(HttpServletRequest request,
		HttpServletResponse response) throws IOException{
	
	
			response.setHeader("Pragma","No-cache");
			response.setHeader("Cache-Control","no-cache");
			response.setDateHeader("Expires", 0);
			response.setContentType("image/jpeg");
			BufferedImage image = new BufferedImage
				(IMG_WIDTH , IMG_HEIGTH , BufferedImage.TYPE_INT_RGB);
			Graphics g = image.getGraphics();
			Random random = new Random();
			g.setColor(getRandColor(200 , 250));
			g.fillRect(1, 1, IMG_WIDTH - 1, IMG_HEIGTH - 1);
			g.setColor(new Color(102 , 102 , 102));
			g.drawRect(0, 0, IMG_WIDTH - 1, IMG_HEIGTH - 1);
			g.setColor(getRandColor(160,200));
			for (int i = 0 ; i < 30 ; i++)
			{
				int x = random.nextInt(IMG_WIDTH - 1);
				int y = random.nextInt(IMG_HEIGTH - 1);
				int xl = random.nextInt(6) + 1;
				int yl = random.nextInt(12) + 1;
				g.drawLine(x , y , x + xl , y + yl);
			}
			g.setColor(getRandColor(160,200));
			for (int i = 0 ; i < 30 ; i++)
			{
				int x = random.nextInt(IMG_WIDTH - 1);
				int y = random.nextInt(IMG_HEIGTH - 1);
				int xl = random.nextInt(12) + 1;
				int yl = random.nextInt(6) + 1;
				g.drawLine(x , y , x - xl , y - yl);
			}
			g.setFont(mFont);
			String sRand = "";
			for (int i = 0 ; i < 4 ; i++)
			{
				String tmp = getRandomChar();
				sRand += tmp;
				g.setColor(new Color(20 + random.nextInt(110)
					,20 + random.nextInt(110)
					,20 + random.nextInt(110)));
				g.drawString(tmp , 15 * i + 10,15);
			}
//			HttpSession session = request.getSession(true);
//			session.setAttribute("rand" , sRand);
//			System.out.println("寫入session"+sRand);
			SecurityUtils.getSubject().getSession().setAttribute("rand" , sRand);
			g.dispose();
			ImageIO.write(image, "JPEG", response.getOutputStream());
		}
		private String getRandomChar()
		{
			int rand = (int)Math.round(Math.random() * 2);
			long itmp = 0;
			char ctmp = '\u0000';
			switch (rand)
			{
				case 1:
					itmp = Math.round(Math.random() * 25 + 65);
					ctmp = (char)itmp;
					return String.valueOf(ctmp);
				case 2:
					itmp = Math.round(Math.random() * 25 + 97);
					ctmp = (char)itmp;
					return String.valueOf(ctmp);
				default :
					itmp = Math.round(Math.random() * 9);
					return  itmp + "";
			}
		
	
	
		}
}