imageservlet.java

新东方软件开发项目

package com.mobile.controller;



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.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class ImageServlet extends HttpServlet {
	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		 request.setCharacterEncoding("GBK");
			response.setContentType("text/html;charset=GBK");
	
		int width = 78;
		int height = 20;
		//创建图片对象
		BufferedImage bim = new BufferedImage(width,height,BufferedImage.TYPE_INT_RGB);
		//获取图片绘图对象
		Graphics g = bim.getGraphics();
		
		//随机产生背景颜色并填充整个图片
		Random rm = new Random();
		g.setColor(new Color(rm.nextInt(155),rm.nextInt(220),rm.nextInt(255)));
		g.fillRect(0,0, width, height);
		
		
		StringBuffer sbf = new StringBuffer("");
		//输出一个数字
		for(int i=0;i<4;i++){
			g.setColor(new Color(rm.nextInt(88),rm.nextInt(188),rm.nextInt(255)));
			g.setFont(new Font("Dotum",Font.BOLD|Font.ITALIC,22));
			int n = rm.nextInt(10);
			sbf.append(n);
			g.drawString(""+n,i*16+5, 18);
		}
		
		//将得到的四个数字保存到session中,以便当用户登录的时候,用来比较
		request.getSession().setAttribute("piccode", sbf.toString());
		
		//输出图片
		ImageIO.write(bim, "JPG", response.getOutputStream());
	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		this.doGet(request, response);
	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occure
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}