很久以前整合过一次SpringBoot和Mybatis,不过那个时候xml配置Mybatis仍是主流，今天心血来潮，通过注解来整合下，网上找资料发现论坛真的是特别乱，各种抄袭，有些甚至抄袭都不完整，哎，只能发个感慨，然后现在成功了也发个博客记录下吧。
下面开始搭建Spring boot+Mybatis
1.新建项目
填好目录和项目名
暂时勾选web就好了，next
finish
一个基础的骨架就出来，完善下目录结构
在pom.xml文件中加入相关依赖
<?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>com.will</groupId>
<artifactId>first-boot</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>first-boot</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<mybatis-spring-boot.version>1.2.0</mybatis-spring-boot.version>
<mysql-connector.version>5.1.39</mysql-connector.version>
<java.version>1.8</java.version>
</properties>
<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-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>${mybatis-spring-boot.version}</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>${mysql-connector.version}</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
建好数据库，分别是建一个user表，加id,name,age三个属性
配置下核心文件application.properties
将
spring.datasource.url
spring.datasource.username
spring.datasource.password
mybatis.typeAliasesPackage
改成自己的就行了，其余属性可以自行去脑补
server.port=8080
#视图层控制 用mvc方式访问templates下的HTML
spring.mvc.view.prefix=classpath:/templates/
spring.mvc.view.suffix=.html
spring.mvc.static-path-pattern=/static/**
spring.thymeleaf.mode=HTML5
spring.thymeleaf.encoding=UTF-8
#spring.thymeleaf.content-type=text/html
#开发时关闭缓存,不然没法看到实时页面
spring.thymeleaf.cache=false
#thymeleaf这样配置就可以直接访问static下的HTML(和mvc访问方式二选一)
spring.thymeleaf.prefix = classpath:/static/
spring.thymeleaf.suffix = .html
spring.datasource.url=jdbc:mysql://localhost:3306/mymessage?useUnicode=true&characterEncoding=utf8
spring.datasource.username=root
spring.datasource.password=
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
mybatis.typeAliasesPackage=com.will.firstboot.entity
在包entity下创建一个实体类user（entity——》user）
package com.will.firstboot.entity;
public class User {
private Integer id;
private String name;
private Integer age;
public Integer getId() {
return id;
}
public String getName() {
return name;
}
public Integer getAge() {
return age;
}
public void setId(Integer id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setAge(Integer age) {
this.age = age;
}
@Override
public String toString() {
return "User{" +
"id=" + id +
", name='" + name + '\'' +
", age=" + age +
'}';
}
}
mapper——》UserMapper
package com.will.firstboot.mapper;
import com.will.firstboot.entity.User;
import org.apache.ibatis.annotations.Select;
import org.springframework.stereotype.Repository;
@Repository
public interface UserMapper {
@Select("SELECT * FROM user WHERE id = #{id}")
User selectUser(int id);
}
service——》UserService
package com.will.firstboot.service;
import com.will.firstboot.entity.User;
import com.will.firstboot.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
@Service
public class UserService {
@Autowired
private UserMapper userMapper;
public User UserService(int id){
return userMapper.selectUser(id);
}
}
controller——》UserController
package com.will.firstboot.controller;
import com.will.firstboot.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class UserController {
@Autowired
private UserService userService;
@RequestMapping("/showUser/{id}")
public String selectUser(@PathVariable int id){
return userService.UserService(id).toString();
}
}
直接去自动生成的启动类启动就好了，我这里叫做FirstBootApplication。。。。。。。
=============分割=======================
你是不是会发现项目启动不起来，会报错Field userMapper in com.will.firstboot.service.UserService required a bean of type 'com.will.firstboot.mapper.UserMapper' that could not be found.
哈哈哈哈，我就是这样报错的，报错的意思是找不到mapper，加个@MapperScan("com.will.firstboot.mapper")注解就好了，反正我看到很多教程各种少注解，启动类如下
package com.will.firstboot;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
@SpringBootApplication
@MapperScan("com.will.firstboot.mapper")
public class FirstBootApplication {
public static void main(String[] args) {
SpringApplication.run(FirstBootApplication.class, args);
}
}
好了，我们启动访问下http://localhost:8080/showUser/1 ok了
有问题欢迎指正，感谢各位。
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假如有出现mysql相关的警告，可以将mysql jar包版本改为 5.1.35
