详解springboot+mybatis多数据源最简解决方案

说起多数据源，一般都来解决那些问题呢，主从模式或者业务比较复杂需要连接不同的分库来支持业务。我们项目是后者的模式，网上找了很多，大都是根据jpa来做多数据源解决方案，要不就是老的spring多数据源解决方案，还有的是利用aop动态切换，感觉有点小复杂，其实我只是想找一个简单的多数据支持而已，折腾了两个小时整理出来，供大家参考。

废话不多说直接上代码吧

配置文件

pom包就不贴了比较简单该依赖的就依赖，主要是数据库这边的配置：

mybatis.config-locations=classpath:mybatis/mybatis-config.xml

spring.datasource.test1.driverclassname = com.mysql.jdbc.driver
spring.datasource.test1.url = jdbc:mysql://localhost:3306/test1?useunicode=true&characterencoding=utf-8
spring.datasource.test1.username = root
spring.datasource.test1.password = root

spring.datasource.test2.driverclassname = com.mysql.jdbc.driver
spring.datasource.test2.url = jdbc:mysql://localhost:3306/test2?useunicode=true&characterencoding=utf-8
spring.datasource.test2.username = root
spring.datasource.test2.password = root

一个test1库和一个test2库，其中test1位主库，在使用的过程中必须制定主库，不然会报错。

数据源配置

@configuration
@mapperscan(basepackages = "com.neo.mapper.test1", sqlsessiontemplateref = "test1sqlsessiontemplate")
public class datasource1config {

  @bean(name = "test1datasource")
  @configurationproperties(prefix = "spring.datasource.test1")
  @primary
  public datasource testdatasource() {
    return datasourcebuilder.create().build();
  }

  @bean(name = "test1sqlsessionfactory")
  @primary
  public sqlsessionfactory testsqlsessionfactory(@qualifier("test1datasource") datasource datasource) throws exception {
    sqlsessionfactorybean bean = new sqlsessionfactorybean();
    bean.setdatasource(datasource);
    bean.setmapperlocations(new pathmatchingresourcepatternresolver().getresources("classpath:mybatis/mapper/test1/*.xml"));
    return bean.getobject();
  }

  @bean(name = "test1transactionmanager")
  @primary
  public datasourcetransactionmanager testtransactionmanager(@qualifier("test1datasource") datasource datasource) {
    return new datasourcetransactionmanager(datasource);
  }

  @bean(name = "test1sqlsessiontemplate")
  @primary
  public sqlsessiontemplate testsqlsessiontemplate(@qualifier("test1sqlsessionfactory") sqlsessionfactory sqlsessionfactory) throws exception {
    return new sqlsessiontemplate(sqlsessionfactory);
  }

}

最关键的地方就是这块了，一层一层注入,先创建datasource，在创建sqlsessionfactory在创建事务，最后包装到sqlsessiontemplate中。其中需要制定分库的mapper文件地址，以及分库到层代码

@mapperscan(basepackages = "com.neo.mapper.test1", sqlsessiontemplateref  = "test1sqlsessiontemplate")

这块的注解就是指明了扫描dao层，并且给dao层注入指定的sqlsessiontemplate。所有@bean都需要按照命名指定正确。

dao层和xml层

dao层和xml需要按照库来分在不同的目录，比如：test1库dao层在com.neo.mapper.test1包下，test2库在com.neo.mapper.test1

public interface user1mapper {

  list<userentity> getall();

  userentity getone(long id);

  void insert(userentity user);

  void update(userentity user);

  void delete(long id);

}

xml层

<?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.neo.mapper.test1.user1mapper" >
  <resultmap id="baseresultmap" type="com.neo.entity.userentity" >
    <id column="id" property="id" jdbctype="bigint" />
    <result column="username" property="username" jdbctype="varchar" />
    <result column="password" property="password" jdbctype="varchar" />
    <result column="user_sex" property="usersex" javatype="com.neo.enums.usersexenum"/>
    <result column="nick_name" property="nickname" jdbctype="varchar" />
  </resultmap>

  <sql id="base_column_list" >
    id, username, password, user_sex, nick_name
  </sql>

  <select id="getall" resultmap="baseresultmap" >
    select 
    <include refid="base_column_list" />
    from users
  </select>

  <select id="getone" parametertype="java.lang.long" resultmap="baseresultmap" >
    select 
    <include refid="base_column_list" />
    from users
    where id = #{id}
  </select>

  <insert id="insert" parametertype="com.neo.entity.userentity" >
    insert into 
      users
      (username,password,user_sex) 
    values
      (#{username}, #{password}, #{usersex})
  </insert>

  <update id="update" parametertype="com.neo.entity.userentity" >
    update 
      users 
    set 
    <if test="username != null">username = #{username},</if>
    <if test="password != null">password = #{password},</if>
    nick_name = #{nickname}
    where 
      id = #{id}
  </update>

  <delete id="delete" parametertype="java.lang.long" >
    delete from
       users 
    where 
       id =#{id}
  </delete>

</mapper>

测试

测试可以使用springboottest,也可以放到controller中，这里只贴controller层的使用

@restcontroller
public class usercontroller {

  @autowired
  private user1mapper user1mapper;

  @autowired
  private user2mapper user2mapper;

  @requestmapping("/getusers")
  public list<userentity> getusers() {
    list<userentity> users=user1mapper.getall();
    return users;
  }

  @requestmapping("/getuser")
  public userentity getuser(long id) {
    userentity user=user2mapper.getone(id);
    return user;
  }

  @requestmapping("/add")
  public void save(userentity user) {
    user2mapper.insert(user);
  }

  @requestmapping(value="update")
  public void update(userentity user) {
    user2mapper.update(user);
  }

  @requestmapping(value="/delete/{id}")
  public void delete(@pathvariable("id") long id) {
    user1mapper.delete(id);
  }

}

最后源码地址在这里

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。