錯誤原因:
Cause: org.apache.ibatis.binding.BindingException: Parameter 'ids' not found. Available parameters are [arg0, collection, list]
代碼如下:
dao:
public List<Employee> getEmpsByConditionForeach(List<Integer> ids);
xml:
<select id="getEmpsByConditionForeach" resultType="com.fenga.mybatis.bean.Employee"> select * from tbl_employee <!-- collection:指定要遍歷的集合: list類型的參數會特殊處理封裝在map中,map的key就叫list item:將當前遍歷出的元素賦值給指定的變量 separator:每個元素之間的分隔符 open:遍歷出所有結果拼接一個開始的字符 close:遍歷出所有結果拼接一個結束的字符 index:索引。遍歷list的時候是index就是索引,item就是當前值 遍歷map的時候index表示的就是map的key,item就是map的值 #{變量名}就能取出變量的值也就是當前遍歷出的元素 --> <foreach collection="ids" item="item_id" separator="," open="where id in(" close=")"> #{item_id} </foreach> </select>
Test:
@Test public void test1() throws IOException { SqlSessionFactory sqlSessionFactory = getSqlSessionFactory(); SqlSession openSession = sqlSessionFactory.openSession(); try { EmployeeMapperDynamicSQL mapper = openSession.getMapper(EmployeeMapperDynamicSQL.class); List<Employee> list = mapper.getEmpsByConditionForeach(Arrays.asList(1,2,3)); for (Employee emp : list) { System.out.println(emp); } }finally { openSession.close(); } }
解決問題:
Parameter 'ids' not found. 意思是沒找到ids這個集合,可以通過@Param給集合命名,如下:
public List<Employee> getEmpsByConditionForeach(@Param("ids")List<Integer> ids);
結果如圖