今天這篇博客主要介紹springboot與mybatis整合操作數據庫，數據源採用阿里的Druid。mybatis可以基於註解也可以基於xml配置。至於怎麼新建maven項目這裏不再做介紹。
1、首先要新建一個maven項目，項目結構如下，注意啓動類的springboot啓動類要在所有類的父一級目錄。
2、pom.xml配置如下：
<?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>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.6.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>
<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>
<!-- druid數據庫連接池 -->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.0.26</version>
</dependency>
<!-- springboot的mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.1.1</version>
</dependency>
<!-- MySql數據庫驅動 -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
</dependency>
<!-- Springboot 熱部署 -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
主要包括數據庫連接池，mapper映射等
#數據庫設置
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test_db
spring.datasource.username=root
spring.datasource.password=root
#--------------------------
# 下面爲連接池的補充設置，應用到上面所有數據源中
# 初始化大小，最小，最大
spring.datasource.initialSize=5
spring.datasource.minIdle=5
spring.datasource.maxActive=20
# 配置獲取連接等待超時的時間
spring.datasource.maxWait=60000
# 配置間隔多久才進行一次檢測，檢測需要關閉的空閒連接，單位是毫秒
spring.datasource.timeBetweenEvictionRunsMillis=60000
# 配置一個連接在池中最小生存的時間，單位是毫秒
spring.datasource.minEvictableIdleTimeMillis=300000
spring.datasource.validationQuery=SELECT 1 FROM DUAL
spring.datasource.testWhileIdle=true
spring.datasource.testOnBorrow=false
spring.datasource.testOnReturn=false
# 打開PSCache，並且指定每個連接上PSCache的大小
spring.datasource.poolPreparedStatements=true
spring.datasource.maxPoolPreparedStatementPerConnectionSize=20
# 配置監控統計攔截的filters，去掉後監控界面sql無法統計，'wall'用於防火牆
spring.datasource.filters=stat,wall,log4j
# 通過connectProperties屬性來打開mergeSql功能；慢SQL記錄
spring.datasource.connectionProperties=druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000
# 合併多個DruidDataSource的監控數據
#spring.datasource.useGlobalDataSourceStat=true
#配置mapper映射
mybatis.mapperLocations=classpath*:com/example/mapper/*.xml
mybatis.typeAliasesPackage=com.example.domainpackage com.example.mapper;
import org.apache.ibatis.annotations.Mapper;
import com.example.domain.User;
@Mapper
public interface UserMapper {
// @Select({"select * from t_user where id=#{id}"})
// User getUserById(@Param("id") Integer id);
User getUserById(Integer id);
}
#配置mapper映射
mybatis.mapperLocations=classpath*:com/example/mapper/*.xml
mybatis.typeAliasesPackage=com.example.domain4、創建sql_userMapper.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
<mapper namespace="com.example.mapper.UserMapper" >
<select id="getUserById" resultType="com.example.domain.User">
select * from t_user where id = #{id,jdbcType=NUMERIC}
</select>
</mapper>6、創建controller類，UserController.java
package com.example.controller;
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 com.example.domain.User;
import com.example.service.UserService;
@RestController
@RequestMapping("/user")
public class UserController {
@Autowired
private UserService userService;
@RequestMapping("/getUserbyId")
public User getUser(@RequestParam String id){
User user= userService.getUserById(Integer.valueOf(id));
return user;
}
}
7、啓動類DemoApplication.java
package com.example;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.transaction.annotation.EnableTransactionManagement;
@SpringBootApplication
//啓註解事務管理
@EnableTransactionManagement
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
8、運行DemoApplication.java，在瀏覽器中輸入
http://localhost:8080/user/getUserbyId?id=1，可以看到返回的數據