mybatis typeHandler自定义类型转换器

Mybatis默认不支持Calendar
解决办法：

mybatis提供了对自定义的类型转换器（typeHandler）的支持，因此我们可以自己编写类型转换器来实现这一自动转换的功能。

实现步骤：

第一步：编写自定义类型转换器

public class CalendarTypeHandler implements TypeHandler<Calendar>{

    @Override
    public Calendar getResult(ResultSet rs, String string) throws SQLException{
        Timestamp time = rs.getTimestamp(string);
        Calendar c = Calendar.getInstance();
        c.setTimeInMillis(time.getTime());
        return c;
    }

    @Override
    public Calendar getResult(ResultSet rs, int i) throws SQLException{
        Timestamp time = rs.getTimestamp(i);
        Calendar c = Calendar.getInstance();
        c.setTimeInMillis(time.getTime());
        return c;
    }

    @Override
    public Calendar getResult(CallableStatement cs, int i) throws SQLException{
        Timestamp time = cs.getTimestamp(i);
        Calendar c = Calendar.getInstance();
        c.setTimeInMillis(time.getTime());
        return c;
    }

    @Override
    public void setParameter(PreparedStatement ps, int i, Calendar t, JdbcType jt) throws SQLException {
        ps.setTimestamp(i, new Timestamp(t.getTimeInMillis()));
    }

}

第二步：注册类型转换器

<?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>

    <typeHandlers>
        <typeHandler handler="com.ndkey.data.mybatis.CalendarTypeHandler" javaType="java.util.Calendar" jdbcType="TIMESTAMP"/>
    </typeHandlers>
</configuration>

第三步： 指定类型转换

<resultMap id="BaseResultMap" type="com.nington.armstrong.fundamental.Partner" >
    <id column="id" property="id" jdbcType="VARCHAR" />
    <result column="concurrency_version" property="concurrencyVersion" jdbcType="INTEGER" />
    <result column="name" property="name" jdbcType="VARCHAR" />
    <result column="create_time" javaType="java.util.Calendar" property="createTime" jdbcType="TIMESTAMP" />
    <result column="update_time" javaType="java.util.Calendar" property="updateTime" jdbcType="TIMESTAMP" />
    <result column="_deleted" property="deleted" jdbcType="TINYINT" />
  </resultMap>

好了，到此mybatis就能将数据库中的类型与java中的类型自动做转换了。