1.建立項目,項目名稱hibernatedemo14,目錄結構如圖所示
2.在項目中建立lib目錄存儲jar檔案,目錄結構如圖所示
3.在src目錄中建立實體類Course,包名(com.mycompany.demo.bean),如圖所示
4.實體類Course的内容如下
package com.mycompany.demo.bean;
public class Course {
private int cid;
private String name;
public Course() {
super();
}
public Course(String name) {
super();
this.name = name;
}
public int getCid() {
return cid;
}
public void setCid(int cid) {
this.cid = cid;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
} 5.在src目錄中建立實體類Course的映射檔案Course.hbm.xml,包名(com.mycompany.demo.bean),如圖所示
6.映射檔案Course.hbm.xml的内容如下
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!--
package:指定<class/>所在的包
-->
<hibernate-mapping package="com.mycompany.demo.bean">
<!--
name:類名
table:表名
catalog:資料庫名稱,預設為hibernate.cfg.xml中配置的資料庫名稱
-->
<class name="Course" table="course">
<meta attribute="class-description">
This class contains the course detail.
</meta>
<!--
name:屬性名
colum:列名
-->
<id name="cid" type="int" column="cid">
<!--
increment:hibernate維護主鍵值
identity:資料庫自增長
sequence:序列
native:根據不同的資料庫選擇生成政策
uuid:通過UUID算法生成,實際使用較多
assigned:手工設定
-->
<generator class="native"/>
</id>
<!--
length:位元組長度
type:字段類型,支援java和hibernate類型
not-null:非空限制
unique:唯一性限制
-->
<property name="name" column="name" />
</class>
</hibernate-mapping> 7.在src目錄中建立實體類Student,包名(com.mycompany.demo.bean),如圖所示
8.實體類Student的内容如下
package com.mycompany.demo.bean;
import java.util.Set;
public class Student {
private int sid;
private String name;
private Set<Course> courses;
public Student() {
super();
}
public Student(String name) {
super();
this.name = name;
}
public int getSid() {
return sid;
}
public void setSid(int sid) {
this.sid = sid;
}
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;
}
} 9.在src目錄中建立實體類Student的映射檔案Student.hbm.xml,包名(com.mycompany.demo.bean),如圖所示
10.映射檔案Student.hbm.xml的内容如下
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<!--
package:指定<class/>所在的包
-->
<hibernate-mapping package="com.mycompany.demo.bean">
<!--
name:類名
table:表名
catalog:資料庫名稱,預設為hibernate.cfg.xml中配置的資料庫名稱
-->
<class name="Student" table="student">
<meta attribute="class-description">
This class contains the student detail.
</meta>
<!--
name:屬性名
colum:列名
-->
<id name="sid" type="int" column="sid">
<!--
increment:hibernate維護主鍵值
identity:資料庫自增長
sequence:序列
native:根據不同的資料庫選擇生成政策
uuid:通過UUID算法生成,實際使用較多
assigned:手工設定
-->
<generator class="native"/>
</id>
<!--
length:位元組長度
type:字段類型,支援java和hibernate類型
not-null:非空限制
unique:唯一性限制
-->
<property name="name" column="name" type="string" length="50" not-null="true" unique="false"/>
<set name="courses" table="student_course" cascade="save-update">
<key column="sid"></key>
<many-to-many class="Course" column="cid"></many-to-many>
</set>
</class>
</hibernate-mapping> 11.在src目錄中建立工具類 HbnUtil,包名(com.mycompany.demo.util),如圖所示
12.工具類 HbnUtil的内容如下
package com.mycompany.demo.util;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
public class HbnUtil {
private static SessionFactory sessionFactory;
public static Session getSession(){
if(sessionFactory == null || sessionFactory.isClosed()){
sessionFactory = new Configuration().configure().buildSessionFactory();
}
return sessionFactory.getCurrentSession();
}
} 13.在src目錄中建立Hibernate的配置檔案hibernate.cfg.xml,如圖所示
14.Hibernate的配置檔案hibernate.cfg.xml的内容如下
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-configuration SYSTEM
"http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">
<hibernate-configuration>
<session-factory>
<!-- 方言,可以從Hibernate核心jar(hibernate-core-x.x.x.Finall.jar)
檔案中的or.hibernate.dialect包中找到相應的類,類的全名就是 -->
<property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
<!-- 驅動 -->
<property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
<!-- 資料庫連接配接位址 -->
<property name="hibernate.connection.url">jdbc:mysql://localhost:3306/test</property>
<!-- 使用者名 -->
<property name="hibernate.connection.username">
root
</property>
<!-- 密碼 -->
<property name="hibernate.connection.password"></property>
<!--
create:每次都新建立,如果存在就删除
create-drop:建立新表,sessionFactory關閉,表會删除
update :表字段增加,會同步,字段減少不同步,資料改變會同步修改
-->
<property name="hibernate.hbm2ddl.auto">update</property>
<!-- 輸出sql -->
<property name="hibernate.show_sql">true</property>
<!-- 格式化sql -->
<property name="hibernate.format_sql">true</property>
<!-- 事務環境一個線程對一個事務
thread:本地事務環境
jta:分布式事務環境
SpringSessionContext:用于ssh整合
-->
<property name="hibernate.current_session_context_class">thread</property>
<!-- 使用c3p0資料源 -->
<property name="hibernate.connection.provider_class">
org.hibernate.c3p0.internal.C3P0ConnectionProvider</property>
<!-- List of XML mapping files -->
<mapping resource="com/mycompany/demo/bean/Course.hbm.xml"/>
<mapping resource="com/mycompany/demo/bean/Student.hbm.xml"/>
</session-factory>
</hibernate-configuration> 15.在項目中建立test目錄存儲測試檔案,檔案名稱TestApp,包名(com.mycompany.demo.bean),目錄結構如圖所示
16.TestApp測試類的内容如下
package com.mycompany.demo.bean;
import java.util.HashSet;
import java.util.Set;
import org.hibernate.Session;
import org.junit.Before;
import org.junit.Test;
import com.mycompany.demo.util.HbnUtil;
public class TestApp {
private Session session;
@Before
public void init(){
session = HbnUtil.getSession();
}
/*
* 單向關聯-多對多(n:n)
*/
@Test
public void testManyToMany(){
try {
session.beginTransaction();
Course course1 = new Course("git");
Course course2 = new Course("gradle");
Set<Course> courses = new HashSet<Course>();
courses.add(course1);
courses.add(course2);
Student student = new Student("xiaoming");
student.setCourses(courses);
session.save(student);
session.getTransaction().commit();
} catch (Exception e) {
session.getTransaction().rollback();
e.printStackTrace();
}
}
} 轉載于:https://blog.51cto.com/suyanzhu/1911670