更新方法struts 2-hibernate-jpa

Question

struts.xml 这是 Struts 类请告诉我使用strut2 hibernate JPA 更新的正确方法关于按 id 更新<struts><package name="com.Attendance" extends="struts-default">    <action name="RegTeacher" class="com.Attendance.TeacherAction" >    <result name="success">/Admin/success.jsp</result>    <result name="error">/Admin/RegistrationTeacher.jsp</result>    <result name="input">/Admin/RegistrationTeacher.jsp</result>    </action>    <action name="EditTeacher" class="com.Attendance.TeacherAction"     method="FindById">    <result name="success">/Admin/UDTeacher.jsp</result>    <result name="input">/Admin/ShowAllTeacher.jsp</result>    </action>    <action name="UDTeacher" class="com.Attendance.TeacherAction"     method="Update">    <result name="success">/Admin/success.jsp</result>    <result name="error">/Admin/UDTeacher.jsp</result>    <result name="input">/Admin/UDTeacher.jsp</result>    </action>   </package>   <constant name="struts.action.excludePattern"    value="/CheckCode,/CheckRegistrationAdmin," />  </struts>`RegTeacher 这是模型/实体类请告诉我用strut2 hibernate JPA更新的正确方法关于按id更新  ` package com.Attendance;   import javax.persistence.*;   @Entity   @Table(name="Teacher")   public class RegTeacher{   @Id   @GeneratedValue(strategy=GenerationType.AUTO)   @Column(name = "id", nullable = false)   private int id;   @Column(name = "LecturerName",unique=true,nullable=false)   private String Name;   @Column(name= "email",unique=true,nullable=false)   private String email;   @Column(name= "pass",nullable=false)   private String Password;   @Column(name="Course",nullable=false)   private String CourseT;   @Column(name= "ClassName",nullable=false)   private String CName; /** setter and getter **/  }`TecaherAction 这是 Action 类

Answer 1

从错误中可以清楚地看出Duplicate entry 'Rajan' for key 'LecturerName'，您尝试的实体Update被视为重复。原因是每次都调用execute方法来保存实体而不是更新它。TeacherAction

您的问题的解决方案是调用动作类的特定（特定于 jsp 页面）方法。尝试在UpdateTeacher.jsp中添加以下代码行

<s:form action="RegTeacher" method="Update" theme="simple" >

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