@InitBinder for spring mvc

Question

我和那个男人有类似的问题 this post

android:name=".PrometheusApplication"

模型Employee有一个变量来自另一个模型Department，OneToOne连接与hibernate

在表单中我选择了部门但是当我提交时我有一些错误......

@InitBinder
protected void initBinder(HttpServletRequest request, ServletRequestDataBinder binder) {
    // we configure custom PropertyEditor for the given type and property
    binder.registerCustomEditor(Department.class, new DepartmentEditor());
}

@RequestMapping(value = { "/new" }, method = RequestMethod.POST)
public String saveEmployee(
        @ModelAttribute @Valid Employee employee,
        BindingResult result,
        ModelMap model ) {

字段“部门”：被拒绝的值1是下拉列表选择中的ID号

<form:select path="department" id="department">
        <form:options items="${departments}" itemValue="id" itemLabel="name"></form:options>
</form:select>



message : Field error in object 'employee' on field 'department': rejected value [1]; codes [methodInvocation.employee.department,methodInvocation.department,methodInvocation.com.websystique.springmvc.model.Department,methodInvocation]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [employee.department,department]; arguments []; default message [department]]; default message [Property 'department' threw exception; nested exception is java.lang.NullPointerException] --

Answer 1

  

AbstractDao的

public void persist(T entity) {
    getSession().saveOrUpdate(entity);
}

  

控制器

@Autowired
DepartmentService depService;

@InitBinder
protected void initBinder(HttpServletRequest request, ServletRequestDataBinder binder) {
    LOGGER.info("@InitBinder " + request);
    binder.registerCustomEditor(Department.class, new DepartmentEditor(depService));
}

  

DepartmentEditor

@Override
public void setAsText(String value) throws IllegalArgumentException {
    LOGGER.info("value = " + value);
    if(!value.isEmpty()){
        Department department;
        try {
            LOGGER.info("value_2 = " + value);
            department = depService.findById(new Integer(value));
            LOGGER.info("value_3 = " + department);
            if (null!=department) {
                setValue(department);
            } else {
                setValue(department);
                LOGGER.info("Error ", new IllegalArgumentException("Binding error. Cannot find userAccount with id  ["+value+"]"));
            }
        } catch (NumberFormatException e) {
            LOGGER.info("This is Error message ", e);
            throw new IllegalArgumentException("Binding error. Invalid id: " + value);
        }
    } else {
        setValue(null);
    }
}