ibatis3 实例代码下载兼ibatis3优劣分析

ibatis3 实例代码下载兼ibatis3优劣分析

作为rapid-framework路线图的一部分,集成ibatis3也是以后要更新的内容之一.

现编写了ibatis3的代码例子. 

 

一.首先我们来看现在的xml mapper关于增删改查的编写

 

 

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//ibatis.apache.org//DTD Mapper 3.0//EN"
"http://ibatis.apache.org/dtd/ibatis-3-mapper.dtd">

<!--
    该文件通过代码生成器自动生成,只需编写模板,可以生成任何代码
     具请查看: http://code.google.com/p/rapid-framework/
-->
<mapper namespace="UserInfo">

    <resultMap id="UserInfoResult" type="com.company.project.model.UserInfo">
    </resultMap>

    <!-- 用于select查询公用抽取的列 -->
    <sql id="commonColumns">
        <![CDATA[
            user_id as userId,
            username as username,
            password as password,
            birth_date as birthDate,
            sex as sex,
            age as age
        ]]>
    </sql>

    <!-- useGeneratedKeys="true" keyProperty="xxx" for sqlserver and mysql -->
    <insert id="insert" parameterType="com.company.project.model.UserInfo"
        useGeneratedKeys="true" keyProperty="userId"
    >
    <![CDATA[
        INSERT INTO
        user_info (
            user_id ,
            username ,
            password ,
            birth_date ,
            sex ,
            age
        ) VALUES (
            #{userId,jdbcType=BIGINT} ,
            #{username,jdbcType=VARCHAR} ,
            #{password,jdbcType=VARCHAR} ,
            #{birthDate,jdbcType=DATE} ,
            #{sex,jdbcType=TINYINT} ,
            #{age,jdbcType=INTEGER}
        )
    ]]>
        <!--
            oracle: order="BEFORE" SELECT sequenceName.nextval AS ID FROM DUAL
            DB2: order="BEFORE"" values nextval for sequenceName
        <selectKey resultType="java.lang.Long" order="BEFORE" keyProperty="userId">
            SELECT sequenceName.nextval AS ID FROM DUAL
        </selectKey>
        -->
    </insert>

    <update id="update" parameterType="com.company.project.model.UserInfo">
    <![CDATA[
        UPDATE user_info SET
            username = #{username,jdbcType=VARCHAR} ,
            password = #{password,jdbcType=VARCHAR} ,
            birth_date = #{birthDate,jdbcType=DATE} ,
            sex = #{sex,jdbcType=TINYINT} ,
            age = #{age,jdbcType=INTEGER}
        WHERE
            user_id = #{userId}
    ]]>
    </update>

    <delete id="delete" parameterType="java.lang.Long">
    <![CDATA[
        delete from user_info where
        user_id = #{id}
    ]]>
    </delete>

    <select id="getById" parameterType="java.lang.Long" resultMap="UserInfoResult">
        select <include refid="commonColumns" />
        <![CDATA[
            from user_info
            where
                user_id = #{id}
        ]]>
    </select>

    <sql id="dynamicWhere">
        <where>
           <if test="userId != null">
                and user_id = #{userId}
            </if>
           <if test="username != null">
                and username = #{username}
            </if>
        </where>
    </sql>

    <select id="count" resultType="long">
        select count(*) from user_info
        <include refid="dynamicWhere"/>
    </select>

    <select id="pageSelect" resultMap="UserInfoResult">
        select <include refid="commonColumns" />
        from user_info
        <include refid="dynamicWhere"/>
        <if test="sortColumns != null and sortColumns.length() != 0">
            ORDER BY ${sortColumns}
        </if>
    </select>


</mapper>

 

 

与ibatis2 sqlmap的主要异同:

1. insert节点现在可以直接指定mysql auto_increment(或是sqlserver identity)的主键生成策略

  useGeneratedKeys="true" keyProperty="userId" 

 

2. insert及update语句对于null字段,beta3现肯定要指定jdbcType,而且现在是只能在表达式里面指定,不知道ibatis3的大佬是如何想的,如下面

  #{userId,jdbcType=BIGINT}  

 还有其它可以配置，如: #{age,javaType=int,jdbcType=NUMERIC,typeHandler=typeHandler}

 

3.动态构造sql部分,test部分采用的是struts2 ognl表达式,还有choose,foreach语句等,跟struts2 tag是否很像呢?

  不过让人郁闷是的, 判断一个字符串非空竟然要写这么长的语句,那位同学知道精简的麻烦告诉我一下,怀念ibatis2的<isNotEmpty>: 

sortColumns != null and sortColumns.length() != 0

 

二.构造SqlSessionFactory,以前的SqlMapClient

 

Reader reader = Resources.getResourceAsReader("Configuration.xml");
SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(reader);
SqlSession session = sessionFactory.openSession();

 

三. 配置文件Configuration.xml

 

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE configuration
PUBLIC "-//ibatis.apache.org//DTD Config 3.0//EN"
"http://ibatis.apache.org/dtd/ibatis-3-config.dtd">
<configuration>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC" />
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver" />
                <property name="url" value="jdbc:mysql://localhost:3306/test?useUnicode=true&amp;characterEncoding=UTF-8" />
                <property name="username" value="root" />
                <property name="password" value="123456" />
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="com/company/project/model/mapper/UserInfoMapper.xml" />
    </mappers>
</configuration>

 

以上就是完整的示例, 具体demo代码下载:  http://rapid-framework.googlecode.com/files/ibatis3_demo.zip

 

 

ibatis3 annotation评价:

难听点,根本是个脑残方案,如果用annotation写,我还不如使用类似jdbc的java代码. 不知道自己优势是在xml文件,瞎跟风.

 

而spring现在还没有对ibatis3集成,不过以后rapid会先与spring发布ibatis3的插件, 只提供生成器模板,现不自己开发集成,等待spring. 当然以后对提供类似ibatis2的基于方言Dialect的分页还是会提供的.

 

 

最后仍然做下广告: rapid-framework, 现最好的项目脚手架

http://code.google.com/p/rapid-framework/