最近在学习Hibernate,先把学习的过程记录一下,方便自己以后复习.
1.使用工具
MyEclipse 10
2.
1）新建Java程序
2）右键程序，选择MyEclipse-> Add Hibernate Capabilities.
会自动生成HibernateSessionFactory.java文件和hibernate.cfg.xml文件
package com.water.testhibernate;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;
/**
* Configures and provides access to Hibernate sessions, tied to the
* current thread of execution. Follows the Thread Local Session
* pattern, see {@link http://hibernate.org/42.html }.
*/
public class HibernateSessionFactory {
/**
* Location of hibernate.cfg.xml file.
* Location should be on the classpath as Hibernate uses
* #resourceAsStream style lookup for its configuration file.
* The default classpath location of the hibernate config file is
* in the default package. Use #setConfigFile() to update
* the location of the configuration file for the current session.
*/
private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";
private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
private static Configuration configuration = new Configuration();
private static org.hibernate.SessionFactory sessionFactory;
private static String configFile = CONFIG_FILE_LOCATION;
static {
try {
configuration.configure(configFile);
sessionFactory = configuration.buildSessionFactory();
} catch (Exception e) {
System.err
.println("%%%% Error Creating SessionFactory %%%%");
e.printStackTrace();
}
}
private HibernateSessionFactory() {
}
/**
* Returns the ThreadLocal Session instance. Lazy initialize
* the <code>SessionFactory</code> if needed.
*
* @return Session
* @throws HibernateException
*/
public static Session getSession() throws HibernateException {
Session session = (Session) threadLocal.get();
if (session == null || !session.isOpen()) {
if (sessionFactory == null) {
rebuildSessionFactory();
}
session = (sessionFactory != null) ? sessionFactory.openSession()
: null;
threadLocal.set(session);
}
return session;
}
/**
* Rebuild hibernate session factory
*
*/
public static void rebuildSessionFactory() {
try {
configuration.configure(configFile);
sessionFactory = configuration.buildSessionFactory();
} catch (Exception e) {
System.err
.println("%%%% Error Creating SessionFactory %%%%");
e.printStackTrace();
}
}
/**
* Close the single hibernate session instance.
*
* @throws HibernateException
*/
public static void closeSession() throws HibernateException {
Session session = (Session) threadLocal.get();
threadLocal.set(null);
if (session != null) {
session.close();
}
}
/**
* return session factory
*
*/
public static org.hibernate.SessionFactory getSessionFactory() {
return sessionFactory;
}
/**
* return session factory
*
* session factory will be rebuilded in the next call
*/
public static void setConfigFile(String configFile) {
HibernateSessionFactory.configFile = configFile;
sessionFactory = null;
}
/**
* return hibernate configuration
*
*/
public static Configuration getConfiguration() {
return configuration;
}
}
创建Grade文件
public class Grade implements Serializable {
private int gid;
private String gname;
private String gdesc;
private Set<Student> students;
public int getGid() {
return gid;
}
public void setGid(int gid) {
this.gid = gid;
}
public String getGname() {
return gname;
}
public void setGname(String gname) {
this.gname = gname;
}
public String getGdesc() {
return gdesc;
}
public void setGdesc(String gdesc) {
this.gdesc = gdesc;
}
public Grade() {
super();
}
public Set<Student> getStudents() {
return students;
}
public void setStudents(Set<Student> students) {
this.students = students;
}
public Grade(int gid, String gname, String gdesc) {
super();
this.gid = gid;
this.gname = gname;
this.gdesc = gdesc;
}
public Grade(String gname, String gdesc) {
super();
this.gname = gname;
this.gdesc = gdesc;
}
}
创建Grade.hbm.xml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.water.model.Grade" table="grade"> <id name="gid" column="gid" type="java.lang.Integer"> <generator class="increment"></generator> </id> <property name="gname" type="java.lang.String"> <column name="gname" length="20" not-null="true"></column> </property> <property name="gdesc"> <column name="gdesc"></column> </property> <!-- 配置一对多关联关系 --> <set name="students" table="student"> <key column="gid"></key> <one-to-many class="com.water.model.Student"/> </set> </class> </hibernate-mapping>
创建Student文件
public class Student implements Serializable {
private int sid;
private String sname;
private String sex;
// 在多方定义一个一方的引用
private Grade grade;
public Grade getGrade() {
return grade;
}
public void setGrade(Grade grade) {
this.grade = grade;
}
public int getSid() {
return sid;
}
public void setSid(int sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Student() {
super();
}
public Student(String sname, String sex) {
super();
this.sname = sname;
this.sex = sex;
}
}
创建Student.hbm.xml 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.water.model.Student" table="student"> <id name="sid" column="sid" type="java.lang.Integer"> <generator class="increment"></generator> </id> <property name="sname" type="java.lang.String"> <column name="sname" length="20" not-null="true"></column> </property> <property name="sex"> <column name="sex"></column> </property> <!-- 配置多对一关联关系 --> <!-- <many-to-one name="grade" class="com.water.model.Grade" column="gid" cascade="all"></many-to-one> --> </class> </hibernate-mapping>
最后hibernate.cfg.xml文件的配置如下：
<?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">
<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-configuration>
<session-factory>
<property name="dialect">org.hibernate.dialect.MySQLDialect</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.username">root</property>
<property name="connection.password">root</property>
<property name="show_sql">true</property>
<!-- create and update the database automaticlly -->
<property name="hbm2ddl.auto">update</property>
<property name="myeclipse.connection.profile">ms_sql</property>
<property name="connection.url">jdbc:mysql://localhost:3306/mysql</property>
<mapping resource="com/water/model/Student.hbm.xml" />
<mapping resource="com/water/model/Grade.hbm.xml" />
</session-factory>
</hibernate-configuration>
<property name="connection.username">root</property>数据库用户名
<property name="connection.password">root</property> 数据库密码
<property name="connection.url">jdbc:mysql://localhost:3306/mysql</property> mysql为数据库名
创建测试类Test.java
public class Test {
public static void main(String[] args) {
add();
}
public static void add(){
Grade g=new Grade("software developer", "Java Android");
Student stu1=new Student("zhasan", "boy");
Student stu2=new Student("lisi", "girl");
Session session=HibernateSessionFactory.getSession();
Transaction tx=session.beginTransaction();
session.save(g);
session.save(stu1);
session.save(stu2);
tx.commit();
HibernateSessionFactory.closeSession();
}
}
运行后的效果如下:
说明已经插入成功.