java web(html页面跳转问题)

html->servlet

emmm怎么说那，一个蠢问题，耽误了好长时间

	<form name = "reg",action="/hello/logServlet" method = get>
	用户名:<input name = "username" type="text" /><br />
	密码:    <input name = "password" type="password" /><br />
	验证码:<input type="text" name="check_code">
		<img src="/hello/CheckServlet"><br />
		<input type="submit" value="提交" id="bt" />
	</form>

怎么样，看出来了吧，多写了个逗号，但是不报错，也不好用

验证码登录源码：

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>登录界面</title>
</head>
<body>
	<form name = "reg" action="/hello/logServlet" method = get>
	用户名:<input name = "username" type="text" /><br />
	密码:    <input name = "password" type="password" /><br />
	验证码:<input type="text" name="check_code">
		<img src="/hello/CheckServlet"><br />
		<input type="submit" value="提交" id="bt" />
	</form>
</body>
</html>

loginServlet

package servlet.test2;
import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.catalina.User;
import servlet.test2.CheckServlet;
@WebServlet("/logServlet")
public class logServlet extends HttpServlet {
	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("text/html;charset=utf-8");
		String username = request.getParameter("username");
		String password = request.getParameter("password");
		String checkCode = request.getParameter("check_code");
		String savedCode = (String) request.getSession().getAttribute("check_code");
		PrintWriter pw = response.getWriter();
		if(("admin").equals(username)&&("admin123").equals(password)
				&&checkCode.equals(savedCode)){
			User user = new User();
			user.setUsername(username);
			user.setPassword(password);
			request.getSession().setAttribute("user", user);
			response.sendRedirect("/hello/main");
		}
		else if (checkCode.equals(savedCode)) {
			pw.write("用户名或密码错误，登录失败");
		}else {
			pw.write("验证码错误");
		}
	}
	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}
	public class User {
		private String username;
		private String password;
		public String getUsername() {
			return username;
		}
		public void setUsername(String username) {
			this.username = username;
		}
		public String getPassword() {
			return password;
		}
		public void setPassword(String password) {
			this.password = password;
		}
	
	}
}

CheckServlet

package servlet.test2;

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

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

@WebServlet("/CheckServlet")
public class CheckServlet extends HttpServlet {
	private static int WIDTH = 60;
	private static int HEIGHT = 20;
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	HttpSession session = request.getSession();
	response.setContentType("img/jpeg");
	ServletOutputStream sos = response.getOutputStream();
	response.setHeader("Pragma", "no-cache");
	response.setDateHeader("Expires", 0);
	BufferedImage image = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_RGB);
	Graphics g = image.getGraphics();
	char [] rands = generateCheckCode();
	drawBackgrounp(g);
	drawRands(g,rands);
	g.dispose();
	ByteArrayOutputStream bos = new ByteArrayOutputStream();
	ImageIO.write(image, "JPEG", bos);
	byte [] buf = bos.toByteArray();
	response.setContentLength(buf.length);
	bos.writeTo(sos);
	session.setAttribute("check_code", new String(rands));
}

private void drawRands(Graphics g, char[] rands) {
	g.setColor(Color.BLACK);
	g.setFont(new Font(null,Font.ITALIC|Font.BOLD,18));
	g.drawString(""+rands[0],1 , 17);
	g.drawString(""+rands[1],16 , 15);
	g.drawString(""+rands[2],31 , 18);
	g.drawString(""+rands[3],46 , 16);
	System.out.println(rands);
	
}

private void drawBackgrounp(Graphics g) {
	g.setColor(new Color(0xDCDCDC));
	g.fillRect(0, 0, WIDTH, HEIGHT);
	for (int i =0;i<120;i++)
	{
		int x = (int) (Math.random()*WIDTH);
		int y = (int) (Math.random()*HEIGHT);
		int red = (int)(Math.random()*255);
		int green = (int)(Math.random()*255);
		int blue = (int)(Math.random()*255);
		g.setColor(new Color(red,green,blue));
		g.drawOval(x, y, 1, 0);
	}
}

private char[] generateCheckCode() {
	String chars = "0123456789qwertyuiopasdfghjklzxcvbnm";
	char [] rands = new char[4];
	for (int i = 0; i<4;i++)
	{
		int rand = (int)(Math.random()*36);
		rands[i] = chars.charAt(rand);
	}
	return rands;
}

public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	// TODO Auto-generated method stub
	doGet(request, response);
}

}

main

package servlet.test2;

import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


@WebServlet("/main")
public class main extends HttpServlet {
	private static final long serialVersionUID = 1L;


	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		response.setContentType("text/html;charset=utf-8");
		String lastAccessTime = null;
		Cookie[] cookies = request.getCookies();
		for (int i =0;cookies != null&&i < cookies.length;i++) {
			if("lastAccess".equals(cookies[i].getName())) {
				lastAccessTime = cookies[i].getValue();
						break;
			}
		}
		if(lastAccessTime == null) {
			response.getWriter().print("你是首次访问本网站！！！");
		}
		else {
			response.getWriter().print("你上次访问的时间是:"+lastAccessTime);
		}
		String currentTime = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss").format(new Date());
		Cookie cookie = new Cookie("lastAccess", currentTime);
		response.addCookie(cookie);
	}


	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(request, response);
	}

}

java web(html页面跳转问题)

html->servlet

验证码登录源码：

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