spring+mybatis+druid数据源+sharding-jdbc分库分表

首先我们看下如何让spring与mybatis集成，我使用的是mysql数据库，建库建表语句如下：

drop database if exists demodb00;
CREATE database demodb00 DEFAULT CHARACTER SET utf8;

CREATE TABLE demodb00.user (
  id int(11) NOT NULL AUTO_INCREMENT,
  name varchar(100) DEFAULT NULL,
  age int(11) DEFAULT NULL,
  PRIMARY KEY (id),
  UNIQUE KEY id_UNIQUE (id)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

编写实体类UserEntity.java

package net.aty.spring.entity;


public class UserEntity {

    private int id;

    private String name;

    private int age;

    public UserEntity() {

    }

    public UserEntity(int id, String name, int age) {
        this.id = id;
        this.name = name;
        this.age = age;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    public String getName() {

        return name;
    }

    public void setName(String name) {
        this.name = name;
    }


    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    @Override
    public String toString() {
        return "UserEntity{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

编写mapper类UserMapper.java

package net.aty.spring.mapper;


import net.aty.spring.entity.UserEntity;

public interface UserMapper {

    int insertOne(UserEntity user);

    UserEntity selectByPk(int id);
}

编写mapper映射文件：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="net.aty.spring.mapper.UserMapper">

    <insert id="insertOne" parameterType="net.aty.spring.entity.UserEntity">
        INSERT INTO user(id, name,age) VALUE(#{id},#{name},#{age})
    </insert>

    <select id="selectByPk" resultType="net.aty.spring.entity.UserEntity" parameterType="java.lang.Integer">
        select * from user where id=#{id}
    </select>

</mapper>

编写mybatis配置文件：mybatis.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!-- 配置mybatis的缓存，延迟加载等等一系列属性 -->
    <settings>
        <!-- 全局映射器启用缓存 -->
        <setting name="cacheEnabled" value="true"/>
        <!-- 查询时，关闭关联对象即时加载以提高性能 -->
        <setting name="lazyLoadingEnabled" value="false"/>
        <!-- 设置关联对象加载的形态，此处为按需加载字段(加载字段由SQL指 定)，不会加载关联表的所有字段，以提高性能 -->
        <setting name="aggressiveLazyLoading" value="true"/>
        <!-- 对于未知的SQL查询，允许返回不同的结果集以达到通用的效果 -->
        <setting name="multipleResultSetsEnabled" value="true"/>
        <!-- 允许使用列标签代替列名 -->
        <setting name="useColumnLabel" value="true"/>
        <!-- 允许使用自定义的主键值(比如由程序生成的UUID 32位编码作为键值)，数据表的PK生成策略将被覆盖 -->
        <!-- <setting name="useGeneratedKeys" value="true" /> -->
        <!-- 给予被嵌套的resultMap以字段-属性的映射支持 -->
        <setting name="autoMappingBehavior" value="FULL"/>
        <!-- 对于批量更新操作缓存SQL以提高性能 -->
        <setting name="defaultExecutorType" value="REUSE"/>
        <!-- 数据库超过25000秒仍未响应则超时 -->
        <setting name="defaultStatementTimeout" value="25000"/>

    </settings>

</configuration>