Mybatis的传参

最近重新温习了遍Mybatis ,觉得还是汇总一下比较好，方便自己以后的快速开发

最终要的一点事，自己写的话，记忆更加深刻；

首先自己先写了个静态块，防止代码冗余：

private static SqlSession session;
    static{
        SqlSessionFactory factory = MybatisUtils.getFactory();
        /**
         * 映射sql的标识字符串
         * com.yc.mybatis.onetoone.classMapper是classMapper.xml文件中mapper标签的namespace属性值
         * getCalss是select标签的id属性值，通过select标签的id属性值就可以找到要执行的sql语句
         */
        session = factory.openSession(true);
    }

First:

常规类型传单个参数：

//传单个参数 (数字类型)
    @Test
    public void test1(){
        String statement = "com.yc.mybatis.test.classMapper.getClass1";
        Classes c = session.selectOne(statement,2);
        System.out.println( c);
        session.close();
    }
    
    //传单个参数(字符类型)
    @Test 
    public void test10(){
        String statement = "com.yc.mybatis.test.classMapper.getClass3";
        Classes c = session.selectOne(statement,"ruanjian1");
        System.out.println( c);
        session.close();
    }

xml

<select id="getClass" parameterType="int" resultMap="getClassMap">
        select * from class c, teacher t  where c.teacher_id = t.t_id and c.teacher_id=#{id}
    </select>

<select id="getClass3" parameterType="string" resultMap="getClassMap">
        select * from class c, teacher t  where c.teacher_id = t.t_id   and c.c_name=#{name}
    </select>

Map传参适用于单个参数

@Test
    public void test11(){
        String statement="com.yc.mybatis.test.classMapper.getClass1";
        Map<Object, Object> c=session.selectMap(statement, 1,"id");
        System.out.println(c);
    }

xml

<select id="getClass1" parameterType="int" resultMap="getClassMap">
        select * from class where c_id=#{id}
    </select>

Map传参多个参数(也适用于单个参数)

@Test
    public void test2(){
        List<Map<String,Object>> list=new ArrayList<Map<String,Object>>();
        Map<String, Object> map=new HashMap<String, Object>();
        map.put("id", 1);
        map.put("name", "ruanjian1");
        String statement="com.yc.mybatis.test.classMapper.getClass2";
        list=session.selectList(statement,map);
        System.out.println(list);
    }

xml

<select id="getClass2" parameterType="hashmap" resultMap="getClassMap">
        select * from class c, teacher t  where c.teacher_id = t.t_id and c.teacher_id=#{id}  and c.c_name=#{name}
    </select>

以对象的形式传参

@Test
    public void test3(){
        Classes c=new Classes();
        c.setName("ruanjian1");
        String statement="com.yc.mybatis.test.classMapper.getClass44";
        List<Object> list=session.selectList(statement,c);
        System.out.println(list);
    }

xml

<select id="getClass44" parameterType="com.yc.bean.Classes" resultMap="getClassMap">
        select * from class c, teacher t  where c.teacher_id = t.t_id   and c.c_name=#{name}
    </select>

Second

对于foreach 你可以传递一个List实例或者数组作为参数对象传给MyBatis。当你这么做的时候，MyBatis会自动将它包装在一个Map中，用名称作为键。List实例将会以“list”作为键，而数组实例将会以“array”作为键。

用list传单个参数变量

@Test
    public void test5(){
        String statement = "com.yc.mybatis.test.classMapper.getClass5";
        List<Integer> list=new ArrayList<Integer>();
        list.add(1);
        list.add(2);
        list.add(3);
        List<Object> c = session.selectList(statement,list);
        for(Object o:c){
            System.out.println( o);
        }
        session.close();
    }

xml

<!-- 
        item: 表示集合中每一个元素进行迭代时的别名
        index: 指定一个名字，用于表示在迭代过程中，每次迭代到的位置;
                     在list和数组中,index是元素的序号，在map中，index是元素的key，该参数可选。
        open: 表示该语句以什么开始，
        separator: 表示在每次进行迭代之间以什么符号作为分隔符，
        close: 表示以什么结束
     -->
    <select id="getClass5" parameterType="list" resultMap="getClassMap">
        select * from class c,teacher t where c.teacher_id=t.t_id and t.t_id in
        <foreach collection="list" item="item" index="index"
            open="(" close=")" separator=",">
            #{item}
        </foreach>
    </select>

用List传数组形式

@Test
    public void test6(){
        String statement = "com.yc.mybatis.test.classMapper.getClass6";
        Integer[] ids={2,3,5};
        List<Object> c = session.selectList(statement,ids);
        for(Object o:c){
            System.out.println( o);
        }
        session.close();
    }

xml

<select id="getClass6" parameterType="list" resultMap="getClassMap">
        select * from class c,teacher t where c.teacher_id=t.t_id and t.t_id in
        <foreach collection="array" item="item" index="index"
            open="(" close=")" separator=",">
            #{item}
        </foreach>
    </select>

用List传map形式

    @Test
    public void test7(){
        String statement = "com.yc.mybatis.test.classMapper.getClass7";
        List<Integer> list=new ArrayList<Integer>();
        list.add(1);
        list.add(2);
        list.add(3);
        Map<String,Object> map=new HashMap<String,Object>();
        map.put("ids", list);
        map.put("name", "ruanjian1");
        List<Object> c = session.selectList(statement,map);
        for(Object o:c){
            System.out.println( o);
        }
        session.close();
    }

xml

<select id="getClass7" parameterType="list" resultMap="getClassMap">
        select * from class c,teacher t where c.teacher_id=t.t_id and  c.c_name=#{name} and t.t_id in
        <foreach collection="ids" item="item" index="index"
            open="(" close=")" separator=",">
            #{item}
        </foreach>
    </select>

代码分享链接：http://pan.baidu.com/s/1gfkLFCf