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Hibernate复合键与另一个表的foregin键-如何避免循环引用？

hibernate

Hibernate复合键与另一个表的foregin键-如何避免循环引用？,hibernate,primary-key,one-to-many,foreign-key-relationship,composite-primary-key,Hibernate,Primary Key,One To Many,Foreign Key Relationship,Composite Primary Key,我有一个学生表，自动生成的id作为主键，一对多映射到电话表 My Phone表有一个复合键PhonePK，其中电话号码和学生表的外键id作为主键 如果我使用phonePk.setStudent，它会工作，但我真的不想这样做。我怎样才能做到这一点？如果无法实现，我希望设置学生id，而不是整个学生对象。我该怎么做？如果有人能对此提供见解，我将不胜感激 student.java import java.io.Serializable; import java.util.Set; import jav

我有一个学生表，自动生成的id作为主键，一对多映射到电话表

My Phone表有一个复合键PhonePK，其中电话号码和学生表的外键id作为主键

如果我使用phonePk.setStudent，它会工作，但我真的不想这样做。我怎样才能做到这一点？如果无法实现，我希望设置学生id，而不是整个学生对象。我该怎么做？如果有人能对此提供见解，我将不胜感激

student.java

import java.io.Serializable;
import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;

@Entity
@SuppressWarnings("serial")
public class Student implements Serializable {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;

private String fName;

private String lName;

private String mName;

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name = "id")
private Set<Phone> phones;

/**
 * @return the fName
 */
public String getfName() {
return fName;
}

/**
 * @return the id
 */
public int getId() {
return id;
}

/**
 * @return the lName
*/
public String getlName() {
return lName;
}

/**
 * @return the mName
 */
public String getmName() {
return mName;
}

/**
* @return the phones
 */
public Set<Phone> getPhones() {
return phones;
}

/**
 * @param fName
 *            the fName to set
 */
public void setfName(final String fName) {
   this.fName = fName;
}

/**
 * @param id
 *            the id to set
 */
public void setId(final int id) {
this.id = id;
}

/**
 * @param lName
 *            the lName to set
 */
public void setlName(final String lName) {
this.lName = lName;
}

/**
 * @param mName
 *            the mName to set
*/
public void setmName(final String mName) {
this.mName = mName;
}

/**
 * @param phones
 *            the phones to set
 */
public void setPhones(final Set<Phone> phones) {
this.phones = phones;
}

}

import java.io.Serializable;

import javax.persistence.EmbeddedId;
import javax.persistence.Entity;

@Entity
@SuppressWarnings("serial")
public class Phone implements Serializable {

@EmbeddedId
 private PhonePK PK;

private String color;

/**
 * @return the color
 */
public String getColor() {
return color;
}

public PhonePK getPK() {
return PK;
}

/**
 * @param color
 *            the color to set
 */
public void setColor(final String color) {
this.color = color;
}

public void setPK(final PhonePK pK) {
PK = pK;
}



} 

import java.io.Serializable;

import javax.persistence.Embeddable;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;

@Embeddable
@SuppressWarnings({ "serial" })
public class PhonePK implements Serializable {

@ManyToOne
 @JoinColumn(name = "id", insertable = false, updatable = false)
 private Student student;

private String phoneNumber;

public String getPhoneNumber() {
return phoneNumber;
}

public Student getStudent() {
return student;
}

public void setPhoneNumber(final String phoneNumber) {
this.phoneNumber = phoneNumber;
}

public void setStudent(final Student student) {
this.student = student;
}



}

import java.util.LinkedHashSet;
import java.util.Set;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class Main {

 public static void main(final String args[]) {

Configuration configuration = new Configuration();
Transaction transaction = null;

configuration.addAnnotatedClass(Student.class);
configuration.addAnnotatedClass(Phone.class);
configuration.configure("hibernate.cfg.xml");
SessionFactory sessionFactory = configuration.buildSessionFactory();
Session session = sessionFactory.openSession();

Student student = new Student();
student.setfName("Bob");
student.setlName("Buster");

Set<Phone> phones = new LinkedHashSet<Phone>();
Phone phone = new Phone();
phone.setColor("Black");
PhonePK phonePK = new PhonePK();
phonePK.setPhoneNumber("1111111111");
phonePK.setStudent(student); // Do not do this? But won't work (id cannot be null  
error) if commented out??
phone.setPK(phonePK);
phones.add(phone);

student.setPhones(phones);

try {
    transaction = session.beginTransaction();
    session.save(student);
    transaction.commit();
} catch (HibernateException e) {
    transaction.rollback();
    e.printStackTrace();
} finally {
    session.close();
}

}
}
PhonePK.java

import java.io.Serializable;
import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;

@Entity
@SuppressWarnings("serial")
public class Student implements Serializable {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;

private String fName;

private String lName;

private String mName;

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name = "id")
private Set<Phone> phones;

/**
 * @return the fName
 */
public String getfName() {
return fName;
}

/**
 * @return the id
 */
public int getId() {
return id;
}

/**
 * @return the lName
*/
public String getlName() {
return lName;
}

/**
 * @return the mName
 */
public String getmName() {
return mName;
}

/**
* @return the phones
 */
public Set<Phone> getPhones() {
return phones;
}

/**
 * @param fName
 *            the fName to set
 */
public void setfName(final String fName) {
   this.fName = fName;
}

/**
 * @param id
 *            the id to set
 */
public void setId(final int id) {
this.id = id;
}

/**
 * @param lName
 *            the lName to set
 */
public void setlName(final String lName) {
this.lName = lName;
}

/**
 * @param mName
 *            the mName to set
*/
public void setmName(final String mName) {
this.mName = mName;
}

/**
 * @param phones
 *            the phones to set
 */
public void setPhones(final Set<Phone> phones) {
this.phones = phones;
}

}

import java.io.Serializable;

import javax.persistence.EmbeddedId;
import javax.persistence.Entity;

@Entity
@SuppressWarnings("serial")
public class Phone implements Serializable {

@EmbeddedId
 private PhonePK PK;

private String color;

/**
 * @return the color
 */
public String getColor() {
return color;
}

public PhonePK getPK() {
return PK;
}

/**
 * @param color
 *            the color to set
 */
public void setColor(final String color) {
this.color = color;
}

public void setPK(final PhonePK pK) {
PK = pK;
}



} 

import java.io.Serializable;

import javax.persistence.Embeddable;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;

@Embeddable
@SuppressWarnings({ "serial" })
public class PhonePK implements Serializable {

@ManyToOne
 @JoinColumn(name = "id", insertable = false, updatable = false)
 private Student student;

private String phoneNumber;

public String getPhoneNumber() {
return phoneNumber;
}

public Student getStudent() {
return student;
}

public void setPhoneNumber(final String phoneNumber) {
this.phoneNumber = phoneNumber;
}

public void setStudent(final Student student) {
this.student = student;
}



}

import java.util.LinkedHashSet;
import java.util.Set;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class Main {

 public static void main(final String args[]) {

Configuration configuration = new Configuration();
Transaction transaction = null;

configuration.addAnnotatedClass(Student.class);
configuration.addAnnotatedClass(Phone.class);
configuration.configure("hibernate.cfg.xml");
SessionFactory sessionFactory = configuration.buildSessionFactory();
Session session = sessionFactory.openSession();

Student student = new Student();
student.setfName("Bob");
student.setlName("Buster");

Set<Phone> phones = new LinkedHashSet<Phone>();
Phone phone = new Phone();
phone.setColor("Black");
PhonePK phonePK = new PhonePK();
phonePK.setPhoneNumber("1111111111");
phonePK.setStudent(student); // Do not do this? But won't work (id cannot be null  
error) if commented out??
phone.setPK(phonePK);
phones.add(phone);

student.setPhones(phones);

try {
    transaction = session.beginTransaction();
    session.save(student);
    transaction.commit();
} catch (HibernateException e) {
    transaction.rollback();
    e.printStackTrace();
} finally {
    session.close();
}

}
}
Main.java

import java.io.Serializable;
import java.util.Set;

import javax.persistence.CascadeType;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;

@Entity
@SuppressWarnings("serial")
public class Student implements Serializable {

@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;

private String fName;

private String lName;

private String mName;

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name = "id")
private Set<Phone> phones;

/**
 * @return the fName
 */
public String getfName() {
return fName;
}

/**
 * @return the id
 */
public int getId() {
return id;
}

/**
 * @return the lName
*/
public String getlName() {
return lName;
}

/**
 * @return the mName
 */
public String getmName() {
return mName;
}

/**
* @return the phones
 */
public Set<Phone> getPhones() {
return phones;
}

/**
 * @param fName
 *            the fName to set
 */
public void setfName(final String fName) {
   this.fName = fName;
}

/**
 * @param id
 *            the id to set
 */
public void setId(final int id) {
this.id = id;
}

/**
 * @param lName
 *            the lName to set
 */
public void setlName(final String lName) {
this.lName = lName;
}

/**
 * @param mName
 *            the mName to set
*/
public void setmName(final String mName) {
this.mName = mName;
}

/**
 * @param phones
 *            the phones to set
 */
public void setPhones(final Set<Phone> phones) {
this.phones = phones;
}

}

import java.io.Serializable;

import javax.persistence.EmbeddedId;
import javax.persistence.Entity;

@Entity
@SuppressWarnings("serial")
public class Phone implements Serializable {

@EmbeddedId
 private PhonePK PK;

private String color;

/**
 * @return the color
 */
public String getColor() {
return color;
}

public PhonePK getPK() {
return PK;
}

/**
 * @param color
 *            the color to set
 */
public void setColor(final String color) {
this.color = color;
}

public void setPK(final PhonePK pK) {
PK = pK;
}



} 

import java.io.Serializable;

import javax.persistence.Embeddable;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;

@Embeddable
@SuppressWarnings({ "serial" })
public class PhonePK implements Serializable {

@ManyToOne
 @JoinColumn(name = "id", insertable = false, updatable = false)
 private Student student;

private String phoneNumber;

public String getPhoneNumber() {
return phoneNumber;
}

public Student getStudent() {
return student;
}

public void setPhoneNumber(final String phoneNumber) {
this.phoneNumber = phoneNumber;
}

public void setStudent(final Student student) {
this.student = student;
}



}

import java.util.LinkedHashSet;
import java.util.Set;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;

public class Main {

 public static void main(final String args[]) {

Configuration configuration = new Configuration();
Transaction transaction = null;

configuration.addAnnotatedClass(Student.class);
configuration.addAnnotatedClass(Phone.class);
configuration.configure("hibernate.cfg.xml");
SessionFactory sessionFactory = configuration.buildSessionFactory();
Session session = sessionFactory.openSession();

Student student = new Student();
student.setfName("Bob");
student.setlName("Buster");

Set<Phone> phones = new LinkedHashSet<Phone>();
Phone phone = new Phone();
phone.setColor("Black");
PhonePK phonePK = new PhonePK();
phonePK.setPhoneNumber("1111111111");
phonePK.setStudent(student); // Do not do this? But won't work (id cannot be null  
error) if commented out??
phone.setPK(phonePK);
phones.add(phone);

student.setPhones(phones);

try {
    transaction = session.beginTransaction();
    session.save(student);
    transaction.commit();
} catch (HibernateException e) {
    transaction.rollback();
    e.printStackTrace();
} finally {
    session.close();
}

}
}

import java.util.LinkedHashSet；
导入java.util.Set；
导入org.hibernate.hibernateeexception；
导入org.hibernate.Session；
导入org.hibernate.SessionFactory；
导入org.hibernate.Transaction；
导入org.hibernate.cfg.Configuration；
公共班机{
公共静态void main（最终字符串参数[]）{
配置=新配置（）；
事务=空；
配置.addAnnotatedClass（Student.class）；
configuration.addAnnotatedClass（Phone.class）；
configure（“hibernate.cfg.xml”）；
SessionFactory SessionFactory=configuration.buildSessionFactory（）；
Session Session=sessionFactory.openSession（）；
学生=新生（）；
student.setfName（“Bob”）；
student.setlName（“Buster”）；
Set phones=new LinkedHashSet（）；
电话=新电话（）；
手机。设置颜色（“黑色”）；
PhonePK PhonePK=新的PhonePK（）；
电话号码（“1111111”）；
phonePK.setStudent（student）；//不这样做？但不起作用（id不能为null
错误）如果注释掉？？
phone.setPK（phonePK）；
电话。添加（电话）；
学生电话；
试一试{
事务=session.beginTransaction（）；
保存（学生）；
commit（）；
}捕获（休眠异常e）{
transaction.rollback（）；
e、 printStackTrace（）；
}最后{
session.close（）；
}
}
}
hibernate.cfg.xml

<?xml version="1.0" encoding="UTF-8"?>  
<!DOCTYPE hibernate-configuration PUBLIC  
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"  
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">  
<hibernate-configuration>  
<session-factory>  
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>  
<property name="hibernate.connection.password">cosmo99</property>  
<property    
name="hibernate.connection.url">jdbc:mysql://localhost:3306/ops_suite</property>  
<property name="hibernate.connection.username">cosmo-security</property>  
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>  
<property name="hbm2ddl.auto">create</property>  
 </session-factory>  
</hibernate-configuration> 


com.mysql.jdbc.Driver
宇宙99
jdbc：mysql://localhost:3306/ops_suite  
宇宙安全
org.hibernate.dialogue.mysqldialogue
创造
如果您不想循环引用，只需将手机设置到学生的手机中即可。如果要将手机与学生链接，则必须拥有整个学生实体。