使用 foreach标签+List「Map」 出现 Source is null for getProperty（null,“XXX“）异常解决

伪代码…

EmployeeController

@RequestMapping("/xxx/xxx") @ResponseBody public List employeeList(HttpServletRequest req, HttpServletResponse resp) { Map map= new HashMap(); map.put("department_id",department_id); List list = EmployeeService.findEmployee(map); return list; }

EmployeeService接口

List findEmployee(Map map);

EmployeeServiceImpl实现类

@Autowired private UserDao userDao; public List findEmployee(Map map) { return EmployeeDao.findEmployee(map); }

EmployeeDao接口

public List<Map> findEmployee(Map map);

EmployeeDao.xml 重点是在下面，报错原代码

<if test="department_id !='' and department_id = 'xxx'"> and sys_user.department_id in <foreach collection="map" item="deptId" open="(" separator="," close=")"> #{deptId} </foreach> </if> <if test="department_id !='' and department_id != 'xxx'"> and user.department_id in <foreach collection="map" item="deptId" open="(" separator="," close=")"> #{deptId} </foreach> </if>

解决：在if标签外加一层判断

<if test="map != null"> <if test="department_id !='' and department_id = 'xxx'"> and sys_user.department_id in <foreach collection="map" item="deptId" open="(" separator="," close=")"> #{deptId} </foreach> </if> </if> <if test="map!=null"> <if test="department_id !='' and department_id != 'xxx'"> and sys_user.department_id in <foreach collection="map" item="deptId" open="(" separator="," close=")"> #{deptId} </foreach> </if> </if>

查了一上午，太浪费时间了。。。