Hibernate Mapping Exception : Repeated column in mapping for entity

Question

There is a mapping exception for a particular entity. Cant figure out from where the problem is arising. I checked all the mappings 3 times from start to end. Still i am getting a Mapping Exception.

Email to employee is mapped only once. but still it is reporting the error repeated mapping

Error is:

Caused by: org.hibernate.MappingException: Repeated column in mapping for entity: com.cluster.entity.Email column: EMPLOYEE_ID (should be mapped with insert="false" update="false")
    at org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:680)
    at org.hibernate.mapping.PersistentClass.checkPropertyColumnDuplication(PersistentClass.java:702)
    at org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:724)
    at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:477)
    at org.hibernate.mapping.RootClass.validate(RootClass.java:268)
    at org.hibernate.cfg.Configuration.validate(Configuration.java:1287)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1729)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1775)
    at com.cluster.util.HibernateUtil.<clinit>(HibernateUtil.java:16)
    ... 1 more

Email Pojo

package com.cluster.entity;

public class Email {

    private int intEmailID;
    private String strEmailName;

    //many to one
    private EmailType emailType;

    //many to one
    private Employee employee;

    public int getIntEmailID() {
        return intEmailID;
    }

    public void setIntEmailID(int intEmailID) {
        this.intEmailID = intEmailID;
    }

    public String getStrEmailName() {
        return strEmailName;
    }

    public void setStrEmailName(String strEmailName) {
        this.strEmailName = strEmailName;
    }

    public EmailType getEmailType() {
        return emailType;
    }

    public void setEmailType(EmailType emailType) {
        this.emailType = emailType;
    }

    public Employee getEmployee() {
        return employee;
    }

    public void setEmployee(Employee employee) {
        this.employee = employee;
    }

}

email.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
        '-//Hibernate/Hibernate Mapping DTD 3.0//EN'
        'http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd'>


<hibernate-mapping package="com.cluster.entity" >
    <class name="Email" table="EMAIL">

        <id name="intEmailID" column="EMAIL_ID"> 
            <generator class="sequence">
                <param name="sequence">EMAIL_ID_SEQ</param>
            </generator>
        </id>

        <property name="strEmailName" column = "EMAIL_NAME"/>

        <many-to-one name="employee" column="EMPLOYEE_ID" not-null = "true" class = "Employee"/>

        <many-to-one name="emailType" column="EMAIL_TYPE_ID" not-null = "true" class = "EmailType"/>

    </class>

</hibernate-mapping>

Related Script

CREATE TABLE EMPLOYEE
(
  EMPLOYEE_ID      NUMBER                       NOT NULL,
  FIRSTNAME        VARCHAR2(20 BYTE)            NOT NULL,
  LASTNAME         VARCHAR2(20 BYTE)            NOT NULL,
  DATE_OF_BIRTH    VARCHAR2(20 BYTE)            NOT NULL,
  SALARY           VARCHAR2(10 BYTE)            NOT NULL,
  DEPARTMENT_ID    NUMBER                       NOT NULL
);


CREATE TABLE EMAIL
(
 EMAIL_ID              NUMBER              NOT NULL,
 EMAIL_NAME            VARCHAR2(40 BYTE)   NOT NULL,
 EMPLOYEE_ID           NUMBER              NOT NULL,
 EMAIL_TYPE_ID         NUMBER              NOT NULL
);


CREATE TABLE EMAIL_TYPE
(
 EMAIL_TYPE_ID         NUMBER              NOT NULL,
 EMAIL_TYPE_NAME       VARCHAR2(40 BYTE)   NOT NULL
);


ALTER TABLE EMPLOYEE ADD 
(
 CONSTRAINT PK_EMPLOYEE_ID
 PRIMARY KEY (EMPLOYEE_ID)
);

ALTER TABLE EMAIL_TYPE ADD 
(
 CONSTRAINT PK_EMAIL_TYPE_ID
 PRIMARY KEY (EMAIL_TYPE_ID)
);

ALTER TABLE EMAIL ADD
(
 CONSTRAINT PK_EMAIL_ID
 PRIMARY KEY (EMAIL_ID)
);

ALTER TABLE EMAIL ADD
( 
 CONSTRAINT FK_EMAIL_EMPLOYEE_ID
 FOREIGN KEY (EMPLOYEE_ID)
 REFERENCES EMPLOYEE (EMPLOYEE_ID)
);

ALTER TABLE EMAIL ADD
( 
 CONSTRAINT FK_EMAIL_EMAIL_TYPE_ID
 FOREIGN KEY (EMAIL_TYPE_ID)
 REFERENCES EMAIL_TYPE (EMAIL_TYPE_ID)
);

Email to employee is mapped only once. but still it is reporting the error repeated mapping

Answer 1

have you set the collection in Employee as inverse?

<bag name="emails" inverse="true">
  <key column="EMPLOYEE_ID" not-null="true">
  ...
</bag>

Answer 2

For those who are using annotations to solve this, the classes should look like this:

@Entity
public class Email {

    @Id
    @GeneratedValue(strategy=GenerationType.SEQUENCE)
    private int intEmailID;

    @Column(insertable = false, updatable = false)
    private int employeeId;

    @ManyToOne
    private EmailType emailType;

    @ManyToOne
    @JoinColumn(name="employeeId")
    private Employee employee;

    // Getters and Setter
}


@Entity
public class Employee {

    @Id
    private int id;

    @OneToMany(cascade = {CascadeType.ALL}, mappedBy="employeeId")
    @PrimaryKeyJoinColumn
    private List<Email> emailList;

    public void setEmailList(List<Email> emailList) {
        this.emailList = emailList
    }

    public List<Email> getEmailList() {
        return emailList;
    }

    // Rest of getters and setters

}

Answer 3

I think you have mapped Employee to Email using oneToMany relation. If yes its nothing wrong but you have to make sure you can insert and update only in one direction

should be mapped with insert="false" update="false" in Employee