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/** * Copyright(C) 2012. * * 模块名称：	登录模块 * 子模块名称：	验证码模块 * * 备注： * * 修改历史：*/package cn.edu.hbcit.smms.servlet.loginservlet;import java.io.IOException;import java.io.PrintWriter;import java.awt.Color;import java.io.IOException;import java.io.OutputStream;import java.util.Random;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;import org.patchca.color.ColorFactory;import org.patchca.color.SingleColorFactory;import org.patchca.filter.predefined.CurvesRippleFilterFactory;import org.patchca.filter.predefined.DiffuseRippleFilterFactory;import org.patchca.filter.predefined.DoubleRippleFilterFactory;import org.patchca.filter.predefined.MarbleRippleFilterFactory;import org.patchca.filter.predefined.WobbleRippleFilterFactory;import org.patchca.font.FontFactory;import org.patchca.font.RandomFontFactory;import org.patchca.service.ConfigurableCaptchaService;import org.patchca.text.renderer.BestFitTextRenderer;import org.patchca.text.renderer.RandomYBestFitTextRenderer;import org.patchca.text.renderer.SimpleTextRenderer;import org.patchca.text.renderer.TextRenderer;import org.patchca.utils.encoder.EncoderHelper;import org.patchca.word.RandomWordFactory;/** * 验证码生成类 * * 本类的简要描述： * 使用开源验证码项目patchca生成 * jar包：patchca-0.5.0.jar * 项目网址：https://code.google.com/p/patchca/ * 项目中文介绍：http://baike.baidu.com/view/6925997.htm?fromTaglist * * @author liwei5946@gmail.com * @version 1.00  2012-6-7 新建类 */public class VerifyCodeServlet extends HttpServlet {	private static final long serialVersionUID = 3796351198097771007L; 	private static ConfigurableCaptchaService ccs = null;	private static ColorFactory cf = null;	private static TextRenderer tr = null;	private static RandomFontFactory ff = null;	private static RandomWordFactory rwf = null;	private static Random r = new Random();	//private static CurvesRippleFilterFactory crff = null;  //干扰线波纹	//private static MarbleRippleFilterFactory mrff = null;  //大理石波纹	//private static DoubleRippleFilterFactory drff = null;  //双波纹	private static WobbleRippleFilterFactory wrff = null;   //摆波纹	//private static DiffuseRippleFilterFactory dirff = null;  //漫波纹	/**	 * Constructor of the object.	 */	public VerifyCodeServlet() {		super();	}		/**	 * Initialization of the servlet. 
	 *	 * @throws ServletException if an error occurs	 */	public void init() throws ServletException {		// Put your code here		super.init();		ccs = new ConfigurableCaptchaService();		cf = new SingleColorFactory(new Color(25, 60, 170));		ff = new RandomFontFactory();		rwf = new RandomWordFactory();		tr = new BestFitTextRenderer();		//crff = new CurvesRippleFilterFactory(ccs.getColorFactory());		//drff = new DoubleRippleFilterFactory();		wrff = new WobbleRippleFilterFactory();		//dirff = new DiffuseRippleFilterFactory();		//mrff = new MarbleRippleFilterFactory();		rwf.setCharacters("123456789");		ff.setRandomStyle(false);		ff.setMaxSize(16);		ff.setMinSize(12);		ccs.setTextRenderer(tr);		ccs.setFontFactory(ff);		ccs.setWordFactory(rwf);		ccs.setColorFactory(cf);		ccs.setWidth(50);		ccs.setHeight(20);	}	/**	 * The doGet method of the servlet. 
	 *	 * 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 {		response.setContentType("image/png");		response.setHeader("cache", "no-cache");		rwf.setMaxLength(4);		rwf.setMinLength(4);		HttpSession session = request.getSession(true);		OutputStream os = response.getOutputStream();		ccs.setFilterFactory(wrff);		/*switch (r.nextInt(5)) {		case 0:			ccs.setFilterFactory(drff);			break;		case 1:			ccs.setFilterFactory(mrff);			break;		case 2:			ccs.setFilterFactory(drff);			break;		case 3:			ccs.setFilterFactory(wrff);			break;		case 4:			ccs.setFilterFactory(dirff);			break;		}*/		String captcha = EncoderHelper.getChallangeAndWriteImage(ccs, "png", os);		session.setAttribute("captcha", captcha);		os.flush();		os.close();	}	/**	 * The doPost method of the servlet. 
	 *	 * 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);	}		/**	 * Destruction of the servlet. 
	 */	public void destroy() {		rwf = null;		cf = null;		ccs = null;		ff = null;		super.destroy(); // Just puts "destroy" string in log		// Put your code here	}}

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