//Students类 外键是classId引用ClassName中的ClassId

package com.hibernate_oneTomany;

import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;

@Entity
@Table(name="t_stu")
public class Students {
 
 private String id;
 
 private String name;
 
 private ClassName clazz;
 
 @Id
 public String getId() {
  return id;
 }

 public void setId(String id) {
  this.id = id;
 }

 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 }

 @ManyToOne
 @JoinColumn(name="classId")
 public ClassName getClazz() {
  return clazz;
 }

 public void setClazz(ClassName clazz) {
  this.clazz = clazz;
 }
 
}

//ClassName是班级类，主键是classId且为Students中classId的外键

package com.hibernate_oneTomany;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;

@Entity
@Table(name="t_class")
public class ClassName {

 private String classId;
 
 private String className;
 
 private Set sets = new HashSet();

 @Id
 @Column(name="classId")
 public String getClassId() {
  return classId;
 }

 public void setClassId(String classId) {
  this.classId = classId;
 }

 public String getClassName() {
  return className;
 }

 public void setClassName(String className) {
  this.className = className;
 }
 
 @OneToMany(mappedBy="clazz")
 public Set getSets() {
  return sets;
 }

 public void setSets(Set sets) {
  this.sets = sets;
 }
}

//测试类

package com.hibernate_oneTomany;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;

public class Test {

 public static void main(String[] args) {
  
  AnnotationConfiguration af = new AnnotationConfiguration();
  SessionFactory sf = af.configure().buildSessionFactory();
  Session session = sf.openSession();
  session.beginTransaction();
  Students stu = new Students();
  ClassName cls = new ClassName();
  cls.setClassId("2");
  cls.setClassName("bb");
  stu.setId("aaa");
  stu.setName("wangwu");
  stu.setClazz(cls);
  
  session.save(cls);
  session.save(stu);
  
  session.beginTransaction().commit();
 }

}

 

//hibernate.cfg.xml中的配置

 "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
 "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">


 
  com.mysql.jdbc.Driver
  jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8
  root
  123
  true
  org.hibernate.dialect.MySQLDialect