자바 생 성 인증 코드

 
 
package cn.net.seek.util;

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

import javax.imageio.ImageIO;

public class ImgZoom {

	//               ，       
	private char mapTable[] = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I',
			'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V',
			'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
			'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
			'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8',
			'9' };
	

	/**
	 *      
	 * @param width     60
	 * @param height     24
	 * @param os    
	 * @return         
	 */
	public String getCertPic(int width, int height, OutputStream os) {
		BufferedImage image = new BufferedImage(width, height,
				BufferedImage.TYPE_INT_RGB);
		//        
		Graphics g = image.getGraphics();

		//      
		Random random = new Random();

		//      
		// g.setColor(getRandColor(200, 250)); //       
		g.setColor(new Color(255, 255, 255));
		g.fillRect(0, 0, width, height);

		//     
		g.setFont(new Font("Times New Roman", Font.PLAIN, 18));

		//     155    ，                  
		g.setColor(getRandColor(160, 200));
		for (int i = 0; i < 155; i++) {
			int x = random.nextInt(width);
			int y = random.nextInt(height);
			int xl = random.nextInt(12);
			int yl = random.nextInt(12);
			g.drawLine(x, y, x + xl, y + yl);
		}

		//          (5 )
		String sRand = "";
		for (int i = 0; i < 5; i++) {
			String rand = mapTable[(int) (mapTable.length * Math.random())]
					+ "";
			sRand += rand;
			//           
			g.setColor(new Color(20 + random.nextInt(110), 20 + random
					.nextInt(110), 20 + random.nextInt(110)));//            ，          ，        
			g.drawString(rand, 10 * i + 3, (int) (Math.random() * 9 + 14));// 14-23	Math.round(Math.random()*(Max-Min)+Min)
		}
		//        
		g.dispose();
		try {
			//        
			ImageIO.write(image, "JPEG", os);
		} catch (IOException e) {
			return "";
		}
		return sRand;
	}

	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);
	}

}