SSM框架之学生信息管理系统（三）

项目结构

管理员登录验证以及设计一个拦截器
数据库
user表

entity类

@Component
public class User {
	private Long id;//用户id，主键、自增
	private String username;//用户名
	private String password;//密码
	省略get和set方法

这里dao层 mapper文件 service只需设计一个查找username这里先省略不写 等到设计user（admin）增删改查时在贴上
下面直接写
Controler类

import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.servlet.ModelAndView;

import com.ischoolbar.programmer.entity.Student;
import com.ischoolbar.programmer.entity.User;
import com.ischoolbar.programmer.service.StudentService;
import com.ischoolbar.programmer.service.UserService;
import com.ischoolbar.programmer.util.CpachaUtil;

/**
 * 系统主页控制器
 * @author llq
 *
 */

@RequestMapping("/system")
@Controller
public class SystemController {
	
	@Autowired
	private UserService userService;
	
	
	@RequestMapping(value = "/index",method=RequestMethod.GET)
	public ModelAndView index(ModelAndView model){
		model.setViewName("system/index");
		return model;
	}
	
	/**
	 * 登陆页面
	 * @param model
	 * @return
	 */
	@RequestMapping(value = "/login",method=RequestMethod.GET)
	public ModelAndView login(ModelAndView model){
		model.setViewName("system/login");
		return model;
	}
	
	/**
	 * 注销登录 
	 * @param request
	 * @return
	 */
	@RequestMapping(value = "/login_out",method=RequestMethod.GET)
	public String loginOut(HttpServletRequest request){
		request.getSession().setAttribute("user", null);
		return "redirect:login";
	}
	
	/**
	 * 登录表单提交
	 * @return
	 */
	@RequestMapping(value = "/login",method=RequestMethod.POST)
	@ResponseBody
	public Map<String, String> login(
			@RequestParam(value="username",required=true) String username,
			@RequestParam(value="password",required=true) String password,
			@RequestParam(value="vcode",required=true) String vcode,
			
			HttpServletRequest request
			){
		Map<String, String> ret = new HashMap<String, String>();
		if(StringUtils.isEmpty(username)){
			ret.put("type", "error");
			ret.put("msg", "用户名不能为空!");
			return ret;
		}
		if(StringUtils.isEmpty(password)){
			ret.put("type", "error");
			ret.put("msg", "密码不能为空!");
			return ret;
		}
		if(StringUtils.isEmpty(vcode)){
			ret.put("type", "error");
			ret.put("msg", "验证码不能为空!");
			return ret;
		}
		String loginCpacha = (String)request.getSession().getAttribute("loginCpacha");
		if(StringUtils.isEmpty(loginCpacha)){
			ret.put("type", "error");
			ret.put("msg", "长时间未操作，会话已失效，请刷新后重试!");
			return ret;
		}
		if(!vcode.toUpperCase().equals(loginCpacha.toUpperCase())){
			ret.put("type", "error");
			ret.put("msg", "验证码错误!");
			return ret;
		}
		request.getSession().setAttribute("loginCpacha", null);
		//从数据库中去查找用户
		
			//管理员
			User user = userService.findByUserName(username);
			if(user == null){
				ret.put("type", "error");
				ret.put("msg", "不存在该用户!");
				return ret;
			}
			if(!password.equals(user.getPassword())){
				ret.put("type", "error");
				ret.put("msg", "密码错误!");
				return ret;
			}
			request.getSession().setAttribute("user", user);
		
		
		ret.put("type", "success");
		ret.put("msg", "登录成功!");
		return ret;
	}
	
	/**
	 * 显示 验证码
	 * @param request
	 * @param vl
	 * @param w
	 * @param h
	 * @param response
	 */
	@RequestMapping(value="/get_cpacha",method=RequestMethod.GET)
	public void getCpacha(HttpServletRequest request,
			@RequestParam(value="vl",defaultValue="4",required=false) Integer vl,
			@RequestParam(value="w",defaultValue="98",required=false) Integer w,
			@RequestParam(value="h",defaultValue="33",required=false) Integer h,
			HttpServletResponse response){
		CpachaUtil cpachaUtil = new CpachaUtil(vl, w, h);
		String generatorVCode = cpachaUtil.generatorVCode();
		request.getSession().setAttribute("loginCpacha", generatorVCode);
		BufferedImage generatorRotateVCodeImage = cpachaUtil.generatorRotateVCodeImage(generatorVCode, true);
		try {
			ImageIO.write(generatorRotateVCodeImage, "gif", response.getOutputStream());
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

拦截器类
import java.util.HashMap;
import java.util.Map;

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

import net.sf.json.JSONObject;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import com.ischoolbar.programmer.entity.User;

/**

• 登录过滤拦截器
• @author llq

*/
public class LoginInterceptor implements HandlerInterceptor{

@Override
public void afterCompletion(HttpServletRequest arg0,
		HttpServletResponse arg1, Object arg2, Exception arg3)
		throws Exception {
	// TODO Auto-generated method stub
	
}

@Override
public void postHandle(HttpServletRequest arg0, HttpServletResponse arg1,
		Object arg2, ModelAndView arg3) throws Exception {
	// TODO Auto-generated method stub
	
}

@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response,
		Object arg2) throws Exception {
	// TODO Auto-generated method stub
	String url = request.getRequestURI();
	//System.out.println("进入拦截器，url = " + url);
	Object user = request.getSession().getAttribute("user");
	if(user == null){
		//表示未登录或者登录状态失效
		System.out.println("未登录或登录失效，url = " + url);
		if("XMLHttpRequest".equals(request.getHeader("X-Requested-With"))){
			//ajax请求
			Map<String, String> ret = new HashMap<String, String>();
			ret.put("type", "error");
			ret.put("msg", "登录状态已失效，请重新去登录!");
			response.getWriter().write(JSONObject.fromObject(ret).toString());
			return false;
		}
		response.sendRedirect(request.getContextPath() + "/system/login");
		return false;
	}
	return true;
}

}
工具类
功能生成验证码

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.util.Random;

/**

• 验证码生成器

• @author llq
  */
  public class CpachaUtil {

  /**

  • 验证码来源
    /
    final private char[] code = {
    ‘2’, ‘3’, ‘4’, ‘5’, ‘6’, ‘7’, ‘8’, ‘9’,
    ‘a’, ‘b’, ‘c’, ‘d’, ‘e’, ‘f’, ‘g’, ‘h’, ‘i’, ‘j’,
    ‘k’, ‘m’, ‘n’, ‘p’, ‘q’, ‘r’, ‘s’, ‘t’, ‘u’, ‘v’,
    ‘w’, ‘x’, ‘y’, ‘z’, ‘A’, ‘B’, ‘C’, ‘D’, ‘E’, ‘F’,
    ‘G’, ‘H’, ‘J’, ‘K’, ‘L’, ‘M’, ‘N’, ‘P’, ‘Q’, ‘R’,
    ‘S’, ‘T’, ‘U’, ‘V’, ‘W’, ‘X’, ‘Y’, ‘Z’
    };
    /*
  • 字体
    /
    final private String[] fontNames = new String[]{
    “黑体”, “宋体”, “Courier”, “Arial”,
    “Verdana”, “Times”, “Tahoma”, “Georgia”};
    /*
  • 字体样式
    */
    final private int[] fontStyles = new int[]{
    Font.BOLD, Font.ITALIC|Font.BOLD
    };

  /**

  • 验证码长度
  • 默认4个字符
    /
    private int vcodeLen = 4;
    /*
  • 验证码图片字体大小
  • 默认17
    /
    private int fontsize = 21;
    /*
  • 验证码图片宽度
    /
    private int width = (fontsize+1)vcodeLen+10;
    /
  • 验证码图片高度
    /
    private int height = fontsize+12;
    /*
  • 干扰线条数
  • 默认3条
    */
    private int disturbline = 3;

  public CpachaUtil(){}

  /**

  • 指定验证码长度
  • @param vcodeLen 验证码长度
    */
    public CpachaUtil(int vcodeLen) {
    this.vcodeLen = vcodeLen;
    this.width = (fontsize+1)*vcodeLen+10;
    }

  /**

  • 指定验证码长度、图片宽度、高度
  • @param vcodeLen
  • @param width
  • @param height
    */
    public CpachaUtil(int vcodeLen,int width,int height) {
    this.vcodeLen = vcodeLen;
    this.width = width;
    this.height = height;
    }

  /**

  • 生成验证码图片

  • @param vcode 要画的验证码

  • @param drawline 是否画干扰线

  • @return
    /
    public BufferedImage generatorVCodeImage(String vcode, boolean drawline){
    //创建验证码图片
    BufferedImage vcodeImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    Graphics g = vcodeImage.getGraphics();
    //填充背景色
    g.setColor(new Color(246, 240, 250));
    g.fillRect(0, 0, width, height);
    if(drawline){
    drawDisturbLine(g);
    }
    //用于生成伪随机数
    Random ran = new Random();
    //在图片上画验证码
    for(int i = 0;i < vcode.length();i++){
    //设置字体
    g.setFont(new Font(fontNames[ran.nextInt(fontNames.length)], fontStyles[ran.nextInt(fontStyles.length)], fontsize));
    //随机生成颜色
    g.setColor(getRandomColor());
    //画验证码
    g.drawString(vcode.charAt(i)+"", ifontsize+10, fontsize+5);
    }
    //释放此图形的上下文以及它使用的所有系统资源
    g.dispose();

    return vcodeImage;
    }
    /**

  • 获得旋转字体的验证码图片

  • @param vcode

  • @param drawline 是否画干扰线

  • @return
    /
    public BufferedImage generatorRotateVCodeImage(String vcode, boolean drawline){
    //创建验证码图片
    BufferedImage rotateVcodeImage = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
    Graphics2D g2d = rotateVcodeImage.createGraphics();
    //填充背景色
    g2d.setColor(new Color(246, 240, 250));
    g2d.fillRect(0, 0, width, height);
    if(drawline){
    drawDisturbLine(g2d);
    }
    //在图片上画验证码
    for(int i = 0;i < vcode.length();i++){
    BufferedImage rotateImage = getRotateImage(vcode.charAt(i));
    g2d.drawImage(rotateImage, null, (int) (this.height * 0.7) * i, 0);
    }
    g2d.dispose();
    return rotateVcodeImage;
    }
    /*

  • 生成验证码

  • @return 验证码
    /
    public String generatorVCode(){
    int len = code.length;
    Random ran = new Random();
    StringBuffer sb = new StringBuffer();
    for(int i = 0;i < vcodeLen;i++){
    int index = ran.nextInt(len);
    sb.append(code[index]);
    }
    return sb.toString();
    }
    /*

  • 为验证码图片画一些干扰线

  • @param g
    /
    private void drawDisturbLine(Graphics g){
    Random ran = new Random();
    for(int i = 0;i < disturbline;i++){
    int x1 = ran.nextInt(width);
    int y1 = ran.nextInt(height);
    int x2 = ran.nextInt(width);
    int y2 = ran.nextInt(height);
    g.setColor(getRandomColor());
    //画干扰线
    g.drawLine(x1, y1, x2, y2);
    }
    }
    /*

  • 获取一张旋转的图片

  • @param c 要画的字符

  • @return
    */
    private BufferedImage getRotateImage(char c){
    BufferedImage rotateImage = new BufferedImage(height, height, BufferedImage.TYPE_INT_ARGB);
    Graphics2D g2d = rotateImage.createGraphics();
    //设置透明度为0
    g2d.setColor(new Color(255, 255, 255, 0));
    g2d.fillRect(0, 0, height, height);
    Random ran = new Random();
    g2d.setFont(new Font(fontNames[ran.nextInt(fontNames.length)], fontStyles[ran.nextInt(fontStyles.length)], fontsize));
    g2d.setColor(getRandomColor());
    double theta = getTheta();
    //旋转图片
    g2d.rotate(theta, height/2, height/2);
    g2d.drawString(Character.toString©, (height-fontsize)/2, fontsize+5);
    g2d.dispose();

    return rotateImage;
    }
    /**

  • @return 返回一个随机颜色
    /
    private Color getRandomColor(){
    Random ran = new Random();
    return new Color(ran.nextInt(220), ran.nextInt(220), ran.nextInt(220));
    }
    /*

  • @return 角度
    */
    private double getTheta(){
    return ((int) (Math.random()*1000) % 2 == 0 ? -1 : 1)*Math.random();
    }

  /**

  • @return 验证码字符个数
    /
    public int getVcodeLen() {
    return vcodeLen;
    }
    /*
  • 设置验证码字符个数
  • @param vcodeLen
    /
    public void setVcodeLen(int vcodeLen) {
    this.width = (fontsize+3)vcodeLen+10;
    this.vcodeLen = vcodeLen;
    }
    /
  • @return 字体大小
    /
    public int getFontsize() {
    return fontsize;
    }
    /*
  • 设置字体大小
  • @param fontsize
    /
    public void setFontsize(int fontsize) {
    this.width = (fontsize+3)vcodeLen+10;
    this.height = fontsize+15;
    this.fontsize = fontsize;
    }
    /
  • @return 图片宽度
    /
    public int getWidth() {
    return width;
    }
    /*
  • 设置图片宽度
  • @param width
    /
    public void setWidth(int width) {
    this.width = width;
    }
    /*
  • @return 图片高度
    /
    public int getHeight() {
    return height;
    }
    /*
  • 设置图片高度
  • @param height
    /
    public void setHeight(int height) {
    this.height = height;
    }
    /*
  • @return 干扰线条数
    /
    public int getDisturbline() {
    return disturbline;
    }
    /*
  • 设置干扰线条数
  • @param disturbline
    */
    public void setDisturbline(int disturbline) {
    this.disturbline = disturbline;
    }

}

登录界面

登陆后的主界面

再次声明此页面模板以及日后设计的网页模板素材都来源于网络