authimg.java

ktv点歌系统前台收银有开包房

package com.ktv.common;

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.awt.*;
import java.awt.image.*;
import java.util.*;
import javax.imageio.ImageIO;

public class AuthImg extends HttpServlet
{

	private static final String CONTENT_TYPE = "text/html; charset=gb2312";
	private Font mFont = new Font("Times New Roman", Font.PLAIN, 17);
	public void init() throws ServletException
	{
		super.init();
	}
	Color getRandColor(int fc,int bc)//获取随机颜色参数
	{
		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);
	}

	public void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
	{
		response.setHeader("Pragma","No-cache");
		response.setHeader("Cache-Control","no-cache");
		response.setDateHeader("Expires", 0);
		response.setContentType("image/jpeg");

		int width=130, height=18;
		BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);

		Graphics g = image.getGraphics();
		Random random = new Random();
		g.setColor(getRandColor(200,250));
		g.fillRect(1, 1, width-1, height-1);
		g.setColor(new Color(102,102,102));
		g.drawRect(0, 0, width-1, height-1);
		g.setFont(mFont);

		g.setColor(getRandColor(160,200));
		for (int i=0;i<155;i++)
		{
			int x = random.nextInt(width - 1);
			int y = random.nextInt(height - 1);
			int xl = random.nextInt(6) + 1;
			int yl = random.nextInt(12) + 1;
			g.drawLine(x,y,x + xl,y + yl);
		}
		for (int i = 0;i < 70;i++)
		{
			int x = random.nextInt(width - 1);
			int y = random.nextInt(height - 1);
			int xl = random.nextInt(12) + 1;
			int yl = random.nextInt(6) + 1;
			g.drawLine(x,y,x - xl,y - yl);
		}

		String sRand="";
		for (int i=0;i<6;i++)
		{
			int itmp = random.nextInt(26) + 65;
			char ctmp = (char)itmp;
			sRand += String.valueOf(ctmp);
			g.setColor(Color.BLACK);
			g.drawString(String.valueOf(ctmp),15*i+20,16);
		}

		HttpSession session = request.getSession(true);
		session.setAttribute("rand",sRand);
		g.dispose();
		ImageIO.write(image, "JPEG", response.getOutputStream());
	}
	public void destroy()
	{
	}
}