PS:ibatis3如何傳遞多個參數有兩個方法:一種是使用java.Map,另一種是使用JavaBean。
當只向xxxMapper.xml文件中傳遞一個參數時,可以簡單的用“_parameter”來接收xxxMapper.java傳遞進來的參數,并代入查詢,比如說這樣:
(1)xxxMapper.java文件中這樣定義:
List<String> selectAllAirportCode(Boolean mapping);
(2)這時在對應的xxxMapper.xml文件中可以使用“_parameter”來接收這個參數:
<select id="selectAllAirportCode" resultType="java.lang.String"parameterType="java.lang.Boolean">select DEPARTURE_AIRPORT from USR_AIR_LINE union selectARRIVAL_AIRPORT from USR_AIR_LINE<if test="_parameter == true">union select REL_DEPARTURE_AIRPORT from USR_AIR_LINE unionselectREL_ARRIVAL_AIRPORT from USR_AIR_LINE</if></select>
但是,如果在xxxMapper.java文件中傳遞進來多個參數,就不能使用上面這種形式來接收參數,這時可以有兩種方案來解決這個問題:
一 向xml文件中傳遞進去一個Map<String, Object>集合,然后xml文件中就可以正常使用Map集合中的各個參數了。
具體實例如下:
(1)xxxMapper.java文件中這樣定義:
List<Airline> findAll(Map<String, Object> parms);
(2)在用到上面定義的具體實現類中給Map傳參:
public List<Airline> findAll(PageInfo page,Airline airline) {HashMap<String,Object> params = new HashMap<String,Object>();params.put("page", page);params.put("airline", airline);return airlineMapper.findAll(params);}(3)此時對應的xxxMapper.xml文件使用“java.util.Map”來接收這個Map集合:
<sql id="sqlfileders"><bind name="fileders"value="#{'id':'ID','departureAirport':'DEPARTURE_AIRPORT','relDepartureAirport':'REL_DEPARTURE_AIRPORT','arrivalAirport':'ARRIVAL_AIRPORT','relArrivalAirport':'REL_ARRIVAL_AIRPORT','popStatus':'POP_STATUS','status':'STATUS','creator':'CREATOR','createTime':'CREATE_TIME'}" /><bind name="javapropertys"value="#{'ID':'id','DEPARTURE_AIRPORT':'departureAirport','REL_DEPARTURE_AIRPORT':'relDepartureAirport','ARRIVAL_AIRPORT':'arrivalAirport','REL_ARRIVAL_AIRPORT':'relArrivalAirport','POP_STATUS':'popStatus','STATUS':'status','CREATOR':'creator','CREATE_TIME':'createTime'}" /></sql><select id="findAll" resultMap="BaseResultMap" parameterType="java.util.Map"><![CDATA[select x.* from (select z.*, rownum numbers from (]]>select<include refid="Base_Column_List" />fromUSR_AIR_LINE<where><if test="airline.departureAirport != null">DEPARTURE_AIRPORT = #{airline.departureAirport}</if><if test="airline.arrivalAirport != null">and ARRIVAL_AIRPORT=#{airline.arrivalAirport}</if><if test="airline.relDepartureAirport != null">and REL_DEPARTURE_AIRPORT =#{airline.relDepartureAirport}</if><if test="airline.relArrivalAirport != null">and REL_ARRIVAL_AIRPORT = #{airline.relArrivalAirport}</if><if test="airline.popStatus != null">and POP_STATUS = #{airline.popStatus}</if><if test="airline.status != null">and STATUS = #{airline.status}</if></where><if test="page.sortName != null"><include refid="sqlfileders" /><bind name="orderfield" value="#this.fileders[page.sortName]" />order by ${orderfield} ${page.sortOrder}</if><![CDATA[ ) z where rownum < ]]>#{page.to}<![CDATA[ ) x where x.numbers >= ]]>#{page.from}</select>注:上面的實例實現的是分頁查詢數據。我們可以發現使用Map來傳遞參數這種形式并不好,因為這樣使得在接口中只有一個Map參數,其他人進行維護的時候并不清楚到底需要向這個Map里面傳遞什么參數進去
二 通過給參數添加@Param注解來解決問題:
(1)給xxxMapper.java文件的方法中的參數添加@Param注解,這個注解中的值對應xml文件中使用到的參數名稱:
Airline selectEffectiveAirline(@Param("departureAirport") String departureAirport,@Param("arrivalAirport") String arrivalAirport,@Param("status") BigDecimal status);(2)此時xxxMapper.xml文件中對應的地方就可以正常使用在@Param注解中對應的值了:
<select id="selectEffectiveAirline" resultMap="BaseResultMap" parameterType="java.util.Map">select<include refid="Base_Column_List" />fromUSR_AIR_LINE<where><if test="departureAirport != null">DEPARTURE_AIRPORT = #{departureAirport}</if><if test="arrivalAirport != null">and ARRIVAL_AIRPORT=#{arrivalAirport}</if><if test="status != null">and STATUS = #{status}</if></where></select>注:需要注意的是if條件判斷中的參數和在SQL語句中寫法是不一樣的,if判斷中的變量是沒有添加#{ }的
下面在單獨給大家介紹下通過Mybatis傳遞多個參數的兩個方法
Map傳遞多個參數
parameterType 可以是別名或完全限定名,map或者java.util.Map,這兩個都是可以的
<select id="selectBlogByMap" parameterType="map" resultType="Blog"> select t.ID, t.title, t.content FROM blog t where t.title = #{h_title} and t.content =#{h_content} </select> public void testSelectByMap() { SqlSession session = sqlSessionFactory.openSession(); Map<String, Object> param=new HashMap<String, Object>(); param.put("h_title", "oracle"); param.put("h_content", "使用序列"); Blog blog = (Blog)session.selectOne("cn.enjoylife.BlogMapper.selectBlogByMap",param); session.close(); System.out.println("blog title:"+blog.getTitle()); } 通過JavaBean傳遞多個參數
<select id="selectBlogByBean" parameterType="Blog" resultType="Blog">select t.ID, t.title, t.contentfrom blog twheret.title = #{title}and t.content =#{content} </select>public void testSelectByBean() { SqlSession session = sqlSessionFactory.openSession(); Blog blog=new Blog(); blog.setTitle("oracle"); blog.setContent("使用序列!"); Blog newBlog = (Blog)session.selectOne("cn.enjoylife.BlogMapper.selectBlogByBean",blog); session.close(); System.out.println("new Blog ID:"+newBlog.getId()); }新聞熱點
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