• MyBatis3-传递多个参数(Multiple Parameters)


    传递多个参数一般用在查询上,比如多个条件组成的查询,有以下方式去实现:

    版本信息:

    MyBatis:3.4.4

    1、自带方法

        <select id="getUserArticlesByLimit" resultMap="resultUserArticleList">
            select user.id,user.userName,user.userAddress,article.id as aid,article.title,article.content from user,article where user.id=article.userid and user.id=#{arg0} limit #{arg1},#{arg2}
        </select>
    public List<Article> getUserArticlesByLimit(int id,int start,int limit);
    List<Article> articles=userMapper.getUserArticlesByLimit(1,0,2); 

    说明,arg0...也可以写成param0...

    2、直接传递对象

        <select id="dynamicIfTest" parameterType="Article" resultType="Article">
            select * from article where 1 = 1
            <if test="title != null">
                and title = #{title}
            </if>
            <if test="content != null">
                and content = #{content}
            </if>
            limit 1
        </select>
    public Article dynamicIfTest(Article article);
                    Article inArticle = new Article();
                    inArticle.setTitle("test_title");
                    Article outArticle = userOperation.dynamicIfTest(inArticle);

    3、使用@Praam标注

        <select id="dynamicChooseTest" resultType="Article">
            select * from article where 1 = 1
            <choose>
                <when test="title != null">
                    and title = #{title}
                </when>
                <when test="content != null">
                    and content = #{content}
                </when>
                <otherwise>
                    and tile = "test_title"
                </otherwise>
            </choose>
        </select>
    public Article dynamicChooseTest(
                @Param("title")
                String title, 
                @Param("content")
                String content);
    Article outArticle2 = userOperation.dynamicChooseTest("test_title",null);

    说明:这种方法同样可以用在一个参数的时候。

    4、使用HashMap

    <select id="getArticleBeanList" resultType="ArticleBean">
      select * from article where id = #{id} and name = #{code}  
    </select>  

    说明:parameterType="hashmap"可以不用写。

    public List<ArticleBean> getArticleBeanList(HashMap map); 
                    HashMap<String, Object> map = new HashMap<String, Object>();
                    map.put("id", 1);
                    map.put("code", "123");                
                    List<Article> articless3 = userOperation.getArticleBeanList(map);

    特殊的HashMap示例,用在foreach节点:

        <select id="dynamicForeach3Test" resultType="Article">
            select * from article where title like "%"#{title}"%" and id in
            <foreach collection="ids" index="index" item="item" open="(" separator="," close=")">
                #{item}
            </foreach>
        </select>
    public List<Article> dynamicForeach3Test(Map<String, Object> params);
                    HashMap<String, Object> map = new HashMap<String, Object>();
                    map.put("title", "title");
                    map.put("ids", new int[]{1,3,6});                
                    List<Article> articless3 = userOperation.dynamicForeach3Test(map);

    5、List结合foreach节点一起使用

        <select id="dynamicForeachTest" resultType="Article">
            select * from article where id in
            <foreach collection="list" index="index" item="item" open="(" separator="," close=")">
                #{item}
            </foreach>
        </select>
    public List<Article> dynamicForeachTest(List<Integer> ids);
                    List<Integer> ids = new ArrayList<Integer>();
                    ids.add(1);
                    ids.add(3);
                    ids.add(6);
                    List<Article> articless = userOperation.dynamicForeachTest(ids);

    6、数组结合foreach节点一起使用

        <select id="dynamicForeach2Test" resultType="Article">
            select * from article where id in
            <foreach collection="array" index="index" item="item" open="(" separator="," close=")">
                #{item}
            </foreach>
        </select>
    public List<Article> dynamicForeach2Test(int[] ids);
                    int[] ids2 = {1,3,6};                
                    List<Article> articless2 = userOperation.dynamicForeach2Test(ids2);

    参考:

    http://www.yihaomen.com/article/java/426.htm

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  • 原文地址:https://www.cnblogs.com/EasonJim/p/7066717.html
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