verifycodeservlet.java

web端随机验证码图片生成

package com.mno5.bbs.util.system.verify;
/**********************************************************************
 *    myniko tools Release 1.0
 *    ?Copyright myniko.com 2003
 ************************************************************************/
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.*;

/**
 * <p>
 * Title: <font color=red>VerifyCode</font>
 * Description:
 * Copyright: Copyright (c) 2002
 * Company: www.myniko.com
 * @author <font color=red>niko </font>
 * @version 1.0
 */
public class VerifyCodeServlet extends HttpServlet
{

    private static final String CONTENT_TYPE = "image/jpeg";
    private static final String SESSION_NAME = "verifyString";
    private static final String COLOR_PARAM_NAME = "color";

    public VerifyCodeServlet()
    {
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response)
        throws ServletException, IOException
    {
        response.setHeader("Pragma", "No-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setDateHeader("Expires", 0L);
        String uri = request.getRequestURI();
        String parameter = uri.split(request.getServletPath())[1];
        String params[] = parameter.split("/");
        String sessionName = params[1];
        if(sessionName == null || sessionName.equals(""))
            sessionName = SESSION_NAME;
        HttpSession session = request.getSession(true);
        VerifyCode verifyCode = (VerifyCode)session.getAttribute(sessionName);
        if(params.length >= 3)
            verifyCode.setFColor(params[2]);
        if(params.length >= 4)
            verifyCode.setBColor(params[3]);
        if(params.length >= 5)
            try
            {
                verifyCode.setStyle(Integer.valueOf(params[4]).intValue());
            }
            catch(Exception exception) { }
        if(params.length >= 6)
            try
            {
                verifyCode.setLength(Integer.valueOf(params[5]).intValue());
            }
            catch(Exception exception1) { }
        response.setContentType(CONTENT_TYPE);
        ServletOutputStream out = response.getOutputStream();
        JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
        encoder.encode(verifyCode.getImage());
        out.flush();
        out.close();
    }
}