下面使用学生-课程为例：
首先是使用注解的方式：
package com.tch.test.hibernate.entity;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
@Entity
public class Student {
private int id;
private String name;
private Set<Course> courses = new HashSet<Course>();
@Id
@GeneratedValue
@Column(name="id")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Column(name="name")
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@ManyToMany
@JoinTable(name="student_course",
joinColumns=@JoinColumn(name="student_Id"),
inverseJoinColumns=@JoinColumn(name="course_Id"))
public Set<Course> getCourses() {
return courses;
}
public void setCourses(Set<Course> courses) {
this.courses = courses;
}
}
package com.tch.test.hibernate.entity;
import java.util.Set;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
@Entity
public class Course {
private int id;
private String name;
private Set<Student> students = new HashSet<Student>();
@Id
@GeneratedValue
@Column(name="id")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
@Column(name="name")
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@ManyToMany(mappedBy="courses")
public Set<Student> getStudents() {
return students;
}
public void setStudents(Set<Student> students) {
this.students = students;
}
}
hibernate.cfg.xml：
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<!-- JDBC connection pool (use the built-in) -->
<!--<property name="connection.pool_size">1</property>-->
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<!--<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>-->
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- format_sql -->
<property name="format_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">update</property>
<mapping class="com.tch.test.hibernate.entity.Course"/>
<mapping class="com.tch.test.hibernate.entity.Student"/>
</session-factory>
</hibernate-configuration>
log4j.properties（查看事务的日志信息）:
### direct log messages to stdout ###
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
### direct messages to file hibernate.log ###
#log4j.appender.file=org.apache.log4j.FileAppender
#log4j.appender.file.File=hibernate.log
#log4j.appender.file.layout=org.apache.log4j.PatternLayout
#log4j.appender.file.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
### set log levels - for more verbose logging change 'info' to 'debug' ###
log4j.rootLogger=warn, stdout
### 查看事务的日志信息
log4j.logger.org.hibernate.transaction=debug
#log4j.logger.org.hibernate=info
log4j.logger.org.hibernate=info
### log HQL query parser activity
#log4j.logger.org.hibernate.hql.ast.AST=debug
### log just the SQL
#log4j.logger.org.hibernate.SQL=debug
### log JDBC bind parameters ###
#log4j.logger.org.hibernate.type=info
#log4j.logger.org.hibernate.type=debug
### log schema export/update ###
#log4j.logger.org.hibernate.tool.hbm2ddl=debug
### log HQL parse trees
#log4j.logger.org.hibernate.hql=debug
### log cache activity ###
#log4j.logger.org.hibernate.cache=debug
### log JDBC resource acquisition
#log4j.logger.org.hibernate.jdbc=debug
### enable the following line if you want to track down connection ###
### leakages when using DriverManagerConnectionProvider ###
#log4j.logger.org.hibernate.connection.DriverManagerConnectionProvider=trace
工具类：
package com.tch.test.hibernate.util;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
//注解的时候使用AnnotationConfiguration
return new AnnotationConfiguration().configure().buildSessionFactory();
}
catch (Throwable ex) {
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
测试类：
public class Test {
@org.junit.Test
public void test1(){
Student student = new Student();
student.setName("张三");
Student student2 = new Student();
student2.setName("李四");
Course course = new Course();
course.setName("数学");
Course course2 = new Course();
course2.setName("英语");
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session session = sessionFactory.getCurrentSession();
try {
session.beginTransaction();
session.save(student);
session.save(student2);
session.save(course);
session.save(course2);
student.getCourses().add(course);
session.getTransaction().commit();
} catch (HibernateException e) {
e.printStackTrace();
session.getTransaction().rollback();
}finally{
sessionFactory.close();
}
}
}
最后就会发现中间表里面加入了记录，说明操作成功。
下面是xml配置方式：
实体类：
package com.tch.test.hibernate.entity;
import java.util.HashSet;
import java.util.Set;
public class Student {
private int id;
private String name;
private Set<Course> courses = new HashSet<Course>();
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Set<Course> getCourses() {
return courses;
}
public void setCourses(Set<Course> courses) {
this.courses = courses;
}
}
package com.tch.test.hibernate.entity;
import java.util.HashSet;
import java.util.Set;
public class Course {
private int id;
private String name;
private Set<Student> students = new HashSet<Student>();
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Set<Student> getStudents() {
return students;
}
public void setStudents(Set<Student> students) {
this.students = students;
}
}
映射文件：
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.tch.test.hibernate.entity.Student" table="student">
<id name="id" column="id" type="java.lang.Integer" length="4">
<generator class="native"/>
</id>
<property name="name" column="name" type="java.lang.String"/>
<set name="courses" table="student_course">
<key column="studentId"></key>
<many-to-many column="courseId" class="com.tch.test.hibernate.entity.Course"></many-to-many>
</set>
</class>
</hibernate-mapping>
<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<class name="com.tch.test.hibernate.entity.Course" table="course">
<id name="id" column="id" type="java.lang.Integer" length="4">
<generator class="native"/>
</id>
<property name="name" column="name" type="java.lang.String"/>
<set name="students" table="student_course">
<key column="courseId"></key>
<many-to-many column="studentId" class="com.tch.test.hibernate.entity.Student"></many-to-many>
</set>
</class>
</hibernate-mapping>
hibernate.cfg.xml：
<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- Database connection settings -->
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://localhost:3306/test</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<!-- JDBC connection pool (use the built-in) -->
<!--<property name="connection.pool_size">1</property>-->
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- Enable Hibernate's automatic session context management -->
<property name="current_session_context_class">thread</property>
<!-- Disable the second-level cache -->
<!--<property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property>-->
<!-- Echo all executed SQL to stdout -->
<property name="show_sql">true</property>
<!-- format_sql -->
<property name="format_sql">true</property>
<!-- Drop and re-create the database schema on startup -->
<property name="hbm2ddl.auto">update</property>
<mapping resource="com/tch/test/hibernate/entity/Student.hbm.xml" />
<mapping resource="com/tch/test/hibernate/entity/Course.hbm.xml" />
</session-factory>
</hibernate-configuration>
工具类：
package com.tch.test.hibernate.util;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HibernateUtil {
private static final SessionFactory sessionFactory = buildSessionFactory();
private static SessionFactory buildSessionFactory() {
try {
// return new AnnotationConfiguration().configure().buildSessionFactory();
return new Configuration().configure().buildSessionFactory();
}
catch (Throwable ex) {
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
return sessionFactory;
}
}
测试类：
public class Test {
@org.junit.Test
public void test1(){
Student student = new Student();
student.setName("张三");
Student student2 = new Student();
student2.setName("李四");
Course course = new Course();
course.setName("数学");
Course course2 = new Course();
course2.setName("英语");
SessionFactory sessionFactory = HibernateUtil.getSessionFactory();
Session session = sessionFactory.getCurrentSession();
try {
session.beginTransaction();
session.save(student);
session.save(student2);
session.save(course);
session.save(course2);
student.getCourses().add(course);
session.getTransaction().commit();
} catch (HibernateException e) {
e.printStackTrace();
session.getTransaction().rollback();
}finally{
sessionFactory.close();
}
}
}
OK，结果一样