springboot 整合mybatis2

版权声明：本文为博主编写文章，未经博主允许转载，转载请注明出处。 https://blog.csdn.net/u012373815/article/details/89296273

1. 导入依赖的jar包

新建maven项目导入 springboot和mybatis所需依赖 配置pom.xml文件如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>cn.abel</groupId>
    <artifactId>springboot-mybatis2</artifactId>
    <version>1.0-SNAPSHOT</version>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.4.RELEASE</version>
        <relativePath/>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

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

        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.2.5</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.40</version>
        </dependency>

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.4</version>
        </dependency>
    </dependencies>

</project>

---

2. 配置文件

在resource 下新建配置文件application.properties，添加数据库连接信息如下

## tomcat配置
server.port=8009
#server.tomcat.maxHttpHeaderSize=8192
server.tomcat.uri-encoding=UTF-8
spring.http.encoding.charset=UTF-8
spring.http.encoding.enabled=true
spring.http.encoding.force=true
spring.risk.encoding=UTF-8
# tomcat最大线程数，默认为200  
server.tomcat.max-threads=800
# session最大超时时间(分钟)，默认为30
server.session-timeout=60

## spring 配置
spring.application.name=springboot-mybatis2
application.main=cn.abel.Application

## LOG
logging.file=./logs/springboot-mybatis2.log


## 主数据源，默认的
spring.datasource.url=jdbc:mysql://localhost:3306/oldMan?autoReconnect=true&useUnicode=true&characterEncoding=utf-8&useSSL=false
spring.datasource.username=root
spring.datasource.password=admin
spring.datasource.driverClassName=com.mysql.jdbc.Driver

spring.datasource.type=com.zaxxer.hikari.HikariDataSource
#最小空闲连接
spring.datasource.min-idle=5
#最大连接数量
spring.datasource.max-active=100
#检测数据库的查询语句
spring.datasource.validation-query=select 1 from dual
#等待连接池分配连接的最大时长（毫秒）
spring.datasource.connection-timeout=60000
#一个连接的生命时长（毫秒）
spring.datasource.max-left-time=60000
#生效超时
spring.datasource.validation-time-out=3000
#一个连接idle状态的最大时长（毫秒）
spring.datasource.idle-time-out=60000
#设置默认字符集
spring.datasource.connection-init-sql= set names utf8mb4

logging.level.cn.abel.dao=debug
#Mapper.xml所在的位置
mybatis.mapper-locations=classpath*:mapper/*Mapper.xml
smybatis.type-aliases-package=cn.abel.bean
#Mapper.xml所在的位置

## pagehelper
pagehelper.helperDialect=mysql
pagehelper.reasonable=true
pagehelper.supportMethodsArguments=true
pagehelper.params=count=countSql

此时Springboot+mybatis的配置阶段已经完成，接下来就可以进行编写业务代码了。

---

3. 实战

配置大致就是如此，然后就是新建java bean（省略，文章底部有源码地址）
新建mapper.xml文件（省略，文章底部有源码地址，关于mapper.xml 文件编写的疑问可以看我以前的springmvc＋mybatis 系列文章）

• 新建dao层。代码如下： 要注意 @Repository @Mapper 注解不要漏掉

import java.util.List;
import java.util.Map;

import cn.abel.bean.User;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;

@Repository
@Mapper
public interface UserDao {

    List<User> getByMap(Map<String, Object> map);

    User getById(Integer id);

    Integer create(User user);

    int update(User user);

    int delete(Integer id);
}

service层要在实现类上添加@service注解，代码如下：

import java.util.List;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import cn.abel.dao.UserDao;
import cn.abel.bean.User;

@Service
public class UserService {
    @Autowired
	private UserDao userDao;
	
	public List<User> getByMap(Map<String,Object> map){
		return userDao.getByMap(map);
	}
	
	public User getById(Integer id){
		return userDao.getById(id);
	}
	
	public User create(User user){
		userDao.create(user);
		return user;
	}
	
	public User update(User user){
		userDao.update(user);
		return user;
	}
	
	public int delete(Integer id){
		return userDao.delete(id);
	}
}

controller层也要加@controller注解 （文章底部源码中未包含controller 部分）

import java.util.List;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
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.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import cn.abel.bean.User;
import cn.abel.service.UserService;

@RequestMapping(value="/users")
@Controller
public class UserController {
	
	@Autowired
	private UserService userService;
	
	
	@RequestMapping(method = RequestMethod.GET)
	@ResponseBody
    public List<User> list(HttpServletRequest request){
		return userService.getByMap(null);
    }
	
	@RequestMapping(value="/{id}", method = RequestMethod.GET)
	@ResponseBody
    public User detail(@PathVariable Integer id){
		return userService.getById(id);
    }
    
    @RequestMapping(method = RequestMethod.POST)
	@ResponseBody
    public User create(@RequestBody User user){
		return userService.create(user);
    }

    @RequestMapping(method = RequestMethod.PUT)
	@ResponseBody
    public User update(@RequestBody User user){
		return userService.update(user);
    }
    
    @RequestMapping(value="/{id}", method = RequestMethod.DELETE)
	@ResponseBody
    public int delete(@PathVariable Integer id){
		return userService.delete(id);
    }
    
}

然后在启动入口类中扫描定义的这些配置类如下：

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

/**
 * @author yyb
 * @time 2019/3/26
 */
@SpringBootApplication
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

}

本文完整源代码：https://github.com/527515025/springBoot/tree/master/springboot-mybatis2