Spring Boot实现增删改查接口

一、概述

最近觉得写Android太无聊了，就简单研究加后端框架吧。

二、环境准备

本次就不描述如何去创建Spring工程了，直接实现真实的注册登录操作。当然这只是个demo很多逻辑不够健全的地方就不做细纠了，毕竟精力有限。
1.mysql环境
2.navicat工具
3.maven环境

三、代码实现

由于代码中很多面向接口编程的，我就不放接口代码了，就只具具体的实现的代码，另外数据库的操作也有很多种，我就尽量使用少引入框架的方式。
1.controller实现.里面有些参数的含义可以参考：https://blog.csdn.net/zhangpower1993/article/details/81878773

package com.stormdzh.study.springdemo.controller.user;

import com.stormdzh.study.springdemo.service.user.impl.UserServiceImpl;
import com.stormdzh.study.springdemo.utils.common.rest.RestResponse;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Map;

/**
 * 参数解析：
 * uid
 * nane
 * psw
 */

@RestController
@RequestMapping(value = "/user")
public class UserController {

    @Autowired
    private UserServiceImpl userService;

    /**
     * 注册接口
     *
     * @param params
     * @return
     */
    @RequestMapping(value = "/register")
    public Object register(@RequestParam Map<String, String> params) {
        Object register = userService.register(params);
        if(register == null) {
            return RestResponse.success(register);
        }else{
            return RestResponse.error("用户已存在！");
        }
    }

    /**
     * 登录接口
     *
     * @param params
     * @return
     */
    @RequestMapping(value = "/login")
    public Object login(@RequestParam Map<String, String> params) {
        Object login = userService.login(params);
        if (login == null) {
            return RestResponse.error("登录失败！");
        } else {
            return RestResponse.success(login);
        }
    }

    /**
     * 登出接口
     *
     * @param params
     * @return
     */
    @RequestMapping(value = "/logout")
    public Object logout(@RequestParam Map<String, String> params) {
        return RestResponse.success(userService.logout(params));
    }

}

2.service的实现

package com.stormdzh.study.springdemo.service.user.impl;

import com.stormdzh.study.springdemo.bean.user.db.DUser;
import com.stormdzh.study.springdemo.dao.user.impl.UserDaoImpl;
import com.stormdzh.study.springdemo.service.user.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import java.util.Map;

@Component
public class UserServiceImpl implements UserService {

    @Autowired
    private UserDaoImpl userDao;

    @Override
    public Object register(Map<String, String> params) {
        DUser user = userDao.query(params);
        if (user == null) {
            userDao.insert(params);
        } else {//用户已经存在

        }
        return user;
    }

    @Override
    public Object login(Map<String, String> params) {
        DUser user = userDao.query(params);
        if (user != null && user.getUname().equals(params.get("name")) && user.getUpsw().equals(params.get("psw"))) {
            return user;
        }
        return null;
    }

    @Override
    public Object logout(Map<String, String> params) {
        userDao.update(params);
        DUser user = userDao.query(params);
        return user;
    }
}

3.dao数据访问层的实现

package com.stormdzh.study.springdemo.dao.user.impl;

import com.stormdzh.study.springdemo.bean.user.db.DUser;
import com.stormdzh.study.springdemo.dao.user.UserDao;
import com.stormdzh.study.springdemo.dao.user.mapper.UsersRowMapper;
import com.stormdzh.study.springdemo.utils.common.AppUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCreator;
import org.springframework.stereotype.Component;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.List;
import java.util.Map;
import java.util.Set;

/**
 * 默认条件是userid
 */
@Component
public class UserDaoImpl implements UserDao {

    public String TABLE_NAME = "tb_users";

    @Autowired
    JdbcTemplate jdbcTemplate;


    @Override
    public void insert(Map<String, String> params) {
        jdbcTemplate.update(new PreparedStatementCreator() {

            @Override
            public PreparedStatement createPreparedStatement(Connection con) throws SQLException {
                String sql = "insert into " + TABLE_NAME + " (uid,uname,upsw) values(?,?,?)";
                PreparedStatement ps = con.prepareStatement(sql);
                ps.setString(1, params.get("uid"));
                ps.setString(2, params.get("name"));
                ps.setString(3, params.get("psw"));
                return ps;
            }
        });


    }

    @Override
    public void delete(Map<String, String> params) {
        String sql = "DELETE FROM " + TABLE_NAME + " WHERE uname = " + "'" + params.get("name") + "'";
        jdbcTemplate.execute(sql);
    }

    @Override
    public void update(Map<String, String> params) {
        String whereStr = "";
        String uid = params.get("uid");
        String uname = params.get("uname");
        if (!AppUtils.isTextEmpty(uid)) {
            whereStr = "uid = " + uid;
        } else if (!AppUtils.isTextEmpty(uname)) {
            whereStr = "uname = '" + uname + "'";
        }

        Set<Map.Entry<String, String>> entrySet = params.entrySet();
        String updateStr = "";
        for (Map.Entry<String, String> entry : entrySet) {
            String key = entry.getKey();
            String value = entry.getValue();
            if (!AppUtils.isTextEmpty(updateStr))
                updateStr = updateStr + " , ";
            updateStr = updateStr + key + "='" + value + "'";
        }
        if (AppUtils.isTextEmpty(updateStr))
            return;

        String sql = "update " + TABLE_NAME + " set " + updateStr + " where " + whereStr;
        System.out.println("updateUser==>" + sql);

        jdbcTemplate.execute(sql);
    }

    @Override
    public DUser query(Map<String, String> params) {
        String sql = "SELECT * FROM " + TABLE_NAME + " WHERE uname = " + "'" + params.get("name") + "'";
        List<DUser> userList = jdbcTemplate.query(sql, new UsersRowMapper());
        if (AppUtils.isEmptyColls(userList)) {
            return null;
        }
        return userList.get(0);
    }
}

4.数据库的依赖以及配置

#数据库配置
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/gkkt?useUnicode=true&useJDBCCompliantTimezoneShift=true&serverTimezone=UTC&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=12345678
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
# 下面方法已经过时
# spring.datasource.driver-class-name=com.mysql.jdbc.Driver

        #数据库依赖
        <!-- 链接mysql -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

四、效果

1.发送注册请求：http://localhost:8080/user/register?name=user1&psw=123，接口和数据都ok。

image.png
image.png
2.发送登录请求：http://localhost:8080/user/login?name=user1&psw=123，调用ok。
image.png