public class User { int id; String username; String password; String realName; String email; String phone; Set<Role> roles;}
UserAction.java
<span style="white-space:pre"> </span>@RequestMapping(value = "list") @ResponseBody public List list(@RequestParam Map map) { List<User> list = userService.list(map); return list; }
<span style="white-space:pre"> </span>@RequestMapping(value = "update")<span style="white-space:pre"> </span>@ResponseBody<span style="white-space:pre"> </span>public User update(User user) {<span style="white-space:pre"> </span>userService.update(user);<span style="white-space:pre"> </span>return user;<span style="white-space:pre"> </span>}
UserService.java
<span style="white-space:pre"> </span>public List<User> list(Map map) { List<User> list = userDAO.list(map); for (User user : list) { user.setRoles(null); } return list; }
因为User类中包含Set成员,由于Hibernate的延迟加载,所以在业务层吧roles置为null了。
所以list方法的返回结果如下:
[{"id":1,"username":"admin","password":"admin","realName":"张三","email":"[email protected]","phone":"23423234","roles":null},{"id":2,"username":"erwt","password":"admin","realName":"张三","email":"[email protected]","phone":"3423432432","roles":null}]
前台用easyui的datagrid控件显示和编辑数据:
<table id="dg" title="用户列表" class="easyui-datagrid" style="width:100%;height:auto;margin:0 auto;" data-options="" idField="id" rownumbers="true" fitColumns="true" singleSelect="true"> <thead> <tr > <th field="id" width="60" data-options="align:'center', halign: 'center'">id</th> <th field="username" width="100" editor="text" data-options="align:'left', halign: 'center'">用户名</th> <!-- 如果field 值easyui datagrid找不到的话,它会使用formatter的规则来绑定数据; --> <th field="password" width="100" editor="text" hidden="true">登录密码</th> <th field="realName" width="100" editor="text" align="center">真实姓名</th> <th field="email" width="160" align="center" editor="text">邮箱</th> <th field="phone" data-options="align:'left', halign: 'center'" width="100" editor="text" >联系电话</th> </tr> </thead> </table>
这样编辑easyui的表格数据后保存,报异常
WARN DefaultHandlerExceptionResolver:189 - Handler execution resulted in exception: org.springframework.validation.BeanPropertyBindingResult: 1 errorsField error in object 'user' on field 'roles': rejected value []; codes [typeMismatch.user.roles,typeMismatch.roles,typeMismatch.java.util.Set,typeMismatch]; arguments [org.springframework.context.support.DefaultMessageSourceResolvable: codes [user.roles,roles]; arguments []; default message [roles]]; default message [Failed to convert property value of type 'java.lang.String' to required type 'java.util.Set' for property 'roles'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [java.lang.String] to required type [com.pelin.webapp.ms.entity.Role] for property 'roles[0]': no matching editors or conversion strategy found]
解决方案:
之前一直以为是springMVC的参数绑定功能和easyui的表格数据编辑功能不兼容,于是就去看源码,希望找到根本原因,弄的头都大了,还是找到原因。后来把roles置null改为roles.clear().居然能正常更新编辑了。
UserService.java
public List<User> list(Map map) { List<User> list = userDAO.list(map); for (User user : list) { user.getRoles().clear(); } return list; }
修改后list返回结果:
[{"id":1,"username":"admin","password":"admin","realName":"张三","email":"[email protected]","phone":"23423234","roles":[]},
{"id":2,"username":"erwt","password":"admin","realName":"张三","email":"[email protected]","phone":"3423432432","roles":[]}]
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