给某个群友的 Mybatis 接收 PostgreSQL array 的例子

Blog.java

package org.mybatis.example;

import java.util.Arrays;
import java.util.List;

public class Blog {
    public int[] getArr() {
        return arr;
    }

    public void setArr(int[] arr) {
        this.arr = arr;
    }

    int[] arr;

    @Override
    public String toString() {
        return "Blog{" +
                "arr=" + Arrays.toString(arr) +
                '}';
    }
}

BlogMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "https://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="org.mybatis.example.BlogMapper">
    <select id="selectBlog" resultMap="aaa">
<!--        select * from Blog;-->
        select '{1, 2, 3, 4}'::int[] as arr;
    </select>
    <resultMap id="aaa" type="org.mybatis.example.Blog" autoMapping="true">
        <result column="arr" property="arr" typeHandler="space.iseki.hashutil.PGArrayInt" />
    </resultMap>
</mapper>

lalala.kt

class PGArrayInt: TypeHandler<IntArray>{
    override fun setParameter(ps: PreparedStatement, i: Int, parameter: IntArray?, jdbcType: JdbcType?) {
        ps.setObject(i, parameter)
    }

    override fun getResult(rs: ResultSet, columnName: String?): IntArray {
        return (rs.getArray(columnName).array as Array<Int>).toIntArray() // 这里 PG setObject 吃 IntArray 但是 getObject 不吃，烦恼
    }

    override fun getResult(rs: ResultSet, columnIndex: Int): IntArray {
        TODO()
    }

    override fun getResult(cs: CallableStatement?, columnIndex: Int): IntArray {
        TODO("Not yet implemented")
    }


}


fun main() {
    val resource = "org/mybatis/example/mybatis-config.xml"
    val inputStream: InputStream = object{}::class.java.classLoader.getResourceAsStream(resource)!!
    val sqlSessionFactory = SqlSessionFactoryBuilder().build(inputStream)
    sqlSessionFactory.openSession().use { session->
        println(session.getMapper(BlogMapper::class.java).selectBlog())
    }
}

mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "https://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="org.postgresql.Driver"/>
                <property name="url" value="jdbc:postgresql://127.0.0.1:5432/postgres"/>
                <property name="username" value="postgres"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="org/mybatis/example/BlogMapper.xml"/>
    </mappers>
</configuration>