我遇到了很大的困難,讓我的映射文件通過Hibernate中的外鍵與元素集合一起工作。 Java將嘗試在下面加載這些文件,並且不會有任何運行時異常,但事件表永遠不會作爲員工的對象加載(它將保持爲空,但從數據庫加載其他任何屬性)。在我的MySQL數據庫,我有以下幾點:幫助Hibernate集合外鍵映射
表:員工
主鍵:用戶名VARCHAR
名VARCHAR
AREACODE INTEGER
電話INTEGER
addressNumber INTEGER
addressLocation VARCHAR
電子郵件VARCHAR
表:活動
主鍵:ID INTEGER
的startDate的DateTime
結束日期的DateTime
客戶名稱VARCHAR
EM ployeeUsername VARCHAR
<?xml version="1.0"?>
<class name="Employee" table="Employees">
<id name="username" column="username" type="string"/>
<many-to-one name="contact" class="Contact" column="username" unique="false" update="false" insert="false" optimistic-lock="true" not-found="exception" embed-xml="true" />
</class>
<class name="Contact" table="Employees">
<id name="username" column="username" type="string"/>
<property name="name" column="name" type="string"/>
<property name="addressNumber" column="addressNumber" type="int"/>
<property name="areacode" column="areacode" type="int"/>
<property name="phone" column="phone" type="int"/>
<property name="addressLocation" column="addressLocation" type="string"/>
<property name="email" column="email" type="string"/>
</class>
<?xml version="1.0"?>
<class name="Event" table="Events">
<id name="ID" column="ID" type="int">
<generator class="assigned"/>
</id>
<property name="startDate" column="startDate" type="date"/>
<property name="endDate" column="endDate" type="date"/>
<property name="customerName" column="customerName" type="string"/>
</class>
<class name="Employee" table="Events" entity-name="Employee2">
<id name="username" column="employeeUsername" type="string"/>
<list name="events" cascade="all">
<key column="employeeUsername"/>
<list-index column="ID"/>
<one-to-many class="Event"/>
</list>
</class>
假設hibernate.cfg.xml文件存在並且有效(如果你覺得這個需要顯示,請讓我知道)。它確實在其映射文件部分包含了這兩個文件。
我有一種感覺,我的錯誤可能是在我的「list」聲明中的事件集合的聲明中。這裏是Java類:
package org.hibernate.employee;
import java.util。日期;
public class Event {private int ID; 私人日期startDate; 私人日期endDate; private String customerName;
public Event(){
System.out.println("blah");
}
/**
* @return the iD
*/
public int getID() {
return ID;
}
/**
* @param id the iD to set
*/
public void setID(int id) {
ID = id;
}
/**
* @return the startDate
*/
public Date getStartDate() {
return startDate;
}
/**
* @param startDate the startDate to set
*/
public void setStartDate(Date startDate) {
this.startDate = startDate;
}
/**
* @return the endDate
*/
public Date getEndDate() {
return endDate;
}
/**
* @param endDate the endDate to set
*/
public void setEndDate(Date endDate) {
this.endDate = endDate;
}
/**
* @return the customerName
*/
public String getCustomerName() {
return customerName;
}
/**
* @param customerName the customerName to set
*/
public void setCustomerName(String customerName) {
this.customerName = customerName;
}
}
/*
*文件:Contact.java */
包org.hibernate.employee;
/** *此類表示員工的聯繫信息。 * */ 公共類聯繫{
private int username; // the contact identifier in the database
private int areacode; // the contact areacode
private int phone; // the contact phone
private String name; // the contact's name
private int addressNumber; // the contact's address number
private String addressLocation; // the contact's address location
private String email; // the contact's email
/**
* Constructs a Contact object.
*/
public Contact() {
}
/**
* @return the areacode
*/
public int getAreacode() {
return areacode;
}
/**
* @param areacode the areacode to set
*/
public void setAreacode(int areacode) {
this.areacode = areacode;
}
/**
* @return the phone
*/
public int getPhone() {
return phone;
}
/**
* @param phone the phone to set
*/
public void setPhone(int phone) {
this.phone = phone;
}
/**
* @return the name
*/
public String getName() {
return name;
}
/**
* @param name the name to set
*/
public void setName(String name) {
this.name = name;
}
/**
* @return the addressNumber
*/
public int getAddressNumber() {
return addressNumber;
}
/**
* @param addressNumber the addressNumber to set
*/
public void setAddressNumber(int addressNumber) {
this.addressNumber = addressNumber;
}
/**
* @return the addressLocation
*/
public String getAddressLocation() {
return addressLocation;
}
/**
* @param addressLocation the addressLocation to set
*/
public void setAddressLocation(String addressLocation) {
this.addressLocation = addressLocation;
}
/**
* @return the email
*/
public String getEmail() {
return email;
}
/**
* @param email the email to set
*/
public void setEmail(String email) {
this.email = email;
}
public String toString(){
String retVal = "";
retVal += "Address: " + this.addressNumber + " " + this.addressLocation + "\n";
retVal += "Email: " + this.email + "\n";
retVal += "Phone: " + this.areacode + " " + this.phone + "\n";
retVal += "Name: " + this.name + "\n";
return retVal;
}
public void setUsername(int username) {
this.username = username;
}
public int getUsername() {
return username;
}
}
/*
*文件:Employee.java */
包org.hibernate.employee; import java.util.List;
/** *此類表示公司數據庫中的員工。 * */ 公共類Employee {
private String username; // the employee's username
private Contact contact; // the employee's contact information
private List events;
/**
* Constructs an Employee object.
*/
public Employee() {
super();
}
/**
* @return the username
*/
public String getUsername() {
return username;
}
/**
* @param username the username to set
*/
public void setUsername(String username) {
this.username = username;
}
/**
* @return the contact
*/
public Contact getContact() {
return contact;
}
/**
* @param contact the contact to set
*/
public void setContact(Contact contact) {
this.contact = contact;
}
/**
* @return the events
*/
public List getEvents() {
return events;
}
/**
* @param events the events to set
*/
public void setEvents(List events) {
this.events = events;
}
public String toString(){
String retVal = "";
System.out.println(events);
retVal += "Username: " + username + "\n";
retVal += "Contact: " + contact + "\n";
return retVal;
}
}
非常感謝您的幫助。 – jds2501 2009-10-30 06:39:45