在线房屋租赁和电子签约系统的设计与实现的系统管理员可以管理租户管理信息，可以对租户管理信息添加修改删除操作。

房源类型管理

系统管理员可以对房源类型信息进行添加，修改，删除操作。

经纪人模块的实现

经纪人注册

经纪人可以注册账号并且登录。

合同文件管理

经纪人登录后，可以对合同文件进行添加修改删除操作。

租户模块的实现

交易订单支付

租户登录后，在后台交易订单里面可以对订单进行支付操作。

我的收藏管理

租户登录后可以在我的收藏管理里面删除自己收藏的信息，也可以查看自己收藏的信息。

四、核心代码

登录相关

package com.controller;


import java.util.Arrays;
import java.util.Calendar;
import java.util.Date;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import com.annotation.IgnoreAuth;
import com.baomidou.mybatisplus.mapper.EntityWrapper;
import com.entity.TokenEntity;
import com.entity.UserEntity;
import com.service.TokenService;
import com.service.UserService;
import com.utils.CommonUtil;
import com.utils.MD5Util;
import com.utils.MPUtil;
import com.utils.PageUtils;
import com.utils.R;
import com.utils.ValidatorUtils;

/**
 * 登录相关
 */
@RequestMapping("users")
@RestController
public class UserController{
	
	@Autowired
	private UserService userService;
	
	@Autowired
	private TokenService tokenService;

	/**
	 * 登录
	 */
	@IgnoreAuth
	@PostMapping(value = "/login")
	public R login(String username, String password, String captcha, HttpServletRequest request) {
		UserEntity user = userService.selectOne(new EntityWrapper<UserEntity>().eq("username", username));
		if(user==null || !user.getPassword().equals(password)) {
			return R.error("账号或密码不正确");
		}
		String token = tokenService.generateToken(user.getId(),username, "users", user.getRole());
		return R.ok().put("token", token);
	}
	
	/**
	 * 注册
	 */
	@IgnoreAuth
	@PostMapping(value = "/register")
	public R register(@RequestBody UserEntity user){
//    	ValidatorUtils.validateEntity(user);
    	if(userService.selectOne(new EntityWrapper<UserEntity>().eq("username", user.getUsername())) !=null) {
    		return R.error("用户已存在");
    	}
        userService.insert(user);
        return R.ok();
    }

	/**
	 * 退出
	 */
	@GetMapping(value = "logout")
	public R logout(HttpServletRequest request) {
		request.getSession().invalidate();
		return R.ok("退出成功");
	}
	
	/**
     * 密码重置
     */
    @IgnoreAuth
	@RequestMapping(value = "/resetPass")
    public R resetPass(String username, HttpServletRequest request){
    	UserEntity user = userService.selectOne(new EntityWrapper<UserEntity>().eq("username", username));
    	if(user==null) {
    		return R.error("账号不存在");
    	}
    	user.setPassword("123456");
        userService.update(user,null);
        return R.ok("密码已重置为：123456");
    }
	
	/**
     * 列表
     */
    @RequestMapping("/page")
    public R page(@RequestParam Map<String, Object> params,UserEntity user){
        EntityWrapper<UserEntity> ew = new EntityWrapper<UserEntity>();
    	PageUtils page = userService.queryPage(params, MPUtil.sort(MPUtil.between(MPUtil.allLike(ew, user), params), params));
        return R.ok().put("data", page);
    }

	/**
     * 列表
     */
    @RequestMapping("/list")
    public R list( UserEntity user){
       	EntityWrapper<UserEntity> ew = new EntityWrapper<UserEntity>();
      	ew.allEq(MPUtil.allEQMapPre( user, "user")); 
        return R.ok().put("data", userService.selectListView(ew));
    }

    /**
     * 信息
     */
    @RequestMapping("/info/{id}")
    public R info(@PathVariable("id") String id){
        UserEntity user = userService.selectById(id);
        return R.ok().put("data", user);
    }
    
    /**
     * 获取用户的session用户信息
     */
    @RequestMapping("/session")
    public R getCurrUser(HttpServletRequest request){
    	Long id = (Long)request.getSession().getAttribute("userId");
        UserEntity user = userService.selectById(id);
        return R.ok().put("data", user);
    }

    /**
     * 保存
     */
    @PostMapping("/save")
    public R save(@RequestBody UserEntity user){
//    	ValidatorUtils.validateEntity(user);
    	if(userService.selectOne(new EntityWrapper<UserEntity>().eq("username", user.getUsername())) !=null) {
    		return R.error("用户已存在");
    	}
        userService.insert(user);
        return R.ok();
    }

    /**
     * 修改
     */
    @RequestMapping("/update")
    public R update(@RequestBody UserEntity user){
//        ValidatorUtils.validateEntity(user);
        userService.updateById(user);//全部更新
        return R.ok();
    }

    /**
     * 删除
     */
    @RequestMapping("/delete")
    public R delete(@RequestBody Long[] ids){
        userService.deleteBatchIds(Arrays.asList(ids));
        return R.ok();
    }
}

文件上传

package com.controller;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.UUID;

import org.apache.commons.io.FileUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpStatus;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.util.ResourceUtils;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import com.annotation.IgnoreAuth;
import com.baomidou.mybatisplus.mapper.EntityWrapper;
import com.entity.ConfigEntity;
import com.entity.EIException;
import com.service.ConfigService;
import com.utils.R;

/**
 * 上传文件映射表
 */
@RestController
@RequestMapping("file")
@SuppressWarnings({"unchecked","rawtypes"})
public class FileController{
	@Autowired
    private ConfigService configService;
	/**
	 * 上传文件
	 */
	@RequestMapping("/upload")
	public R upload(@RequestParam("file") MultipartFile file,String type) throws Exception {
		if (file.isEmpty()) {
			throw new EIException("上传文件不能为空");
		}
		String fileExt = file.getOriginalFilename().substring(file.getOriginalFilename().lastIndexOf(".")+1);
		File path = new File(ResourceUtils.getURL("classpath:static").getPath());
		if(!path.exists()) {
		    path = new File("");
		}
		File upload = new File(path.getAbsolutePath(),"/upload/");
		if(!upload.exists()) {
		    upload.mkdirs();
		}
		String fileName = new Date().getTime()+"."+fileExt;
		File dest = new File(upload.getAbsolutePath()+"/"+fileName);
		file.transferTo(dest);
		FileUtils.copyFile(dest, new File("C:\\Users\\Desktop\\jiadian\\springbootl7own\\src\\main\\resources\\static\\upload"+"/"+fileName));
		if(StringUtils.isNotBlank(type) && type.equals("1")) {
			ConfigEntity configEntity = configService.selectOne(new EntityWrapper<ConfigEntity>().eq("name", "faceFile"));
			if(configEntity==null) {
				configEntity = new ConfigEntity();
				configEntity.setName("faceFile");
				configEntity.setValue(fileName);
			} else {
				configEntity.setValue(fileName);
			}
			configService.insertOrUpdate(configEntity);
		}
		return R.ok().put("file", fileName);
	}
	
	/**
	 * 下载文件
	 */
	@IgnoreAuth
	@RequestMapping("/download")
	public ResponseEntity<byte[]> download(@RequestParam String fileName) {
		try {
			File path = new File(ResourceUtils.getURL("classpath:static").getPath());
			if(!path.exists()) {
			    path = new File("");
			}
			File upload = new File(path.getAbsolutePath(),"/upload/");
			if(!upload.exists()) {
			    upload.mkdirs();
			}
			File file = new File(upload.getAbsolutePath()+"/"+fileName);
			if(file.exists()){
				/*if(!fileService.canRead(file, SessionManager.getSessionUser())){
					getResponse().sendError(403);
				}*/
				HttpHeaders headers = new HttpHeaders();
			    headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);    
			    headers.setContentDispositionFormData("attachment", fileName);    
			    return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),headers, HttpStatus.CREATED);
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
		return new ResponseEntity<byte[]>(HttpStatus.INTERNAL_SERVER_ERROR);
	}
	
}

封装

package com.utils;

import java.util.HashMap;
import java.util.Map;

/**
 * 返回数据
 */
public class R extends HashMap<String, Object> {
	private static final long serialVersionUID = 1L;
	
	public R() {
		put("code", 0);
	}
	
	public static R error() {
		return error(500, "未知异常，请联系管理员");
	}
	
	public static R error(String msg) {
		return error(500, msg);
	}
	
	public static R error(int code, String msg) {
		R r = new R();
		r.put("code", code);
		r.put("msg", msg);
		return r;
	}

	public static R ok(String msg) {
		R r = new R();
		r.put("msg", msg);
		return r;
	}
	
	public static R ok(Map<String, Object> map) {
		R r = new R();
		r.putAll(map);
		return r;
	}
	
	public static R ok() {
		return new R();
	}

	public R put(String key, Object value) {
		super.put(key, value);
		return this;
	}
}