时间长了对hibernate的基础使用有点生疏,于是决定重新温习一下。
一.登录hibernate官方,下载hibernate相关jar包。
将下载的压缩包解压:在该hibernate-release-4.2.20.Final\lib\required 路径下的找到hibernate所需要的jar包,将该目录下所有jar包加入工程。
二.hibernate配置文件。
配置文件可以在快速开始文档的工程里找到 参考路径:hibernate-release-4.2.20.Final\documentation\quickstart\en-US\html\files,在该文件下有一个压缩包,将其解压,可以看到示例工程,随便一个工程都能找到配置文件
下面是basic工程的配置文件
<?xml version='1.0' encoding='utf-8'?> <!-- ~ Hibernate, Relational Persistence for Idiomatic Java ~ ~ Copyright (c) 2010, Red Hat Inc. or third-party contributors as ~ indicated by the @author tags or express copyright attribution ~ statements applied by the authors. All third-party contributions are ~ distributed under license by Red Hat Inc. ~ ~ This copyrighted material is made available to anyone wishing to use, modify, ~ copy, or redistribute it subject to the terms and conditions of the GNU ~ Lesser General Public License, as published by the Free Software Foundation. ~ ~ This program is distributed in the hope that it will be useful, ~ but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY ~ or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License ~ for more details. ~ ~ You should have received a copy of the GNU Lesser General Public License ~ along with this distribution; if not, write to: ~ Free Software Foundation, Inc. ~ 51 Franklin Street, Fifth Floor ~ Boston, MA 02110-1301 USA --> <!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">org.h2.Driver</property> <property name="connection.url">jdbc:h2:mem:db1;DB_CLOSE_DELAY=-1;MVCC=TRUE</property> <property name="connection.username">sa</property> <property name="connection.password"/> <!-- JDBC connection pool (use the built-in) --> <property name="connection.pool_size">1</property> <!-- SQL dialect --> <property name="dialect">org.hibernate.dialect.H2Dialect</property> <!-- Disable the second-level cache --> <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property> <!-- Echo all executed SQL to stdout --> <property name="show_sql">true</property> <!-- Drop and re-create the database schema on startup --> <property name="hbm2ddl.auto">create</property> <mapping resource="org/hibernate/tutorial/hbm/Event.hbm.xml"/> </session-factory> </hibernate-configuration>
找到对应位置,更换自己的数据库就好了。
三.创建测试用例。
Student类:
package com.daxingzsh.po; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.FetchType; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.JoinColumn; import javax.persistence.ManyToOne; import javax.persistence.Table; import org.hibernate.annotations.GenericGenerator; @Entity @Table(name = "STUDENT") public class Student { private String sId; private String sName; private String sSex; private Classes classes; @Id @GeneratedValue(generator = "system-uuid") @GenericGenerator(name = "system-uuid", strategy = "uuid") @Column(name = "S_ID") public String getsId() { return sId; } public void setsId(String sId) { this.sId = sId; } @Column(name = "S_NAME") public String getsName() { return sName; } public void setsName(String sName) { this.sName = sName; } @Column(name = "S_SEX") public String getsSex() { return sSex; } public void setsSex(String sSex) { this.sSex = sSex; } @ManyToOne(fetch = FetchType.LAZY) @JoinColumn(name = "CLASS_ID") public Classes getClasses() { return classes; } public void setClasses(Classes classes) { this.classes = classes; } @Override public String toString() { return "Student [sId=" + sId + ", sName=" + sName + ", sSex=" + sSex + ", classes=" + classes + "]"; } }
Classes类:
package com.daxingzsh.po; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.Id; import javax.persistence.Table; import org.hibernate.annotations.GenericGenerator; @Entity @Table(name = "CLASSES_TABLE") public class Classes { private String classId; private String className; @Id @GeneratedValue(generator = "system-uuid") @GenericGenerator(name = "system-uuid", strategy = "uuid") @Column(name = "CLASS_ID") public String getClassId() { return classId; } public void setClassId(String classId) { this.classId = classId; } @Column(name = "CLASS_NAME") public String getClassName() { return className; } public void setClassName(String className) { this.className = className; } }
Student与Classes为N-1(多对一)关系。由于在配置文件中配置了
<property name="hbm2ddl.auto">create</property>
属性,这里hibernate将自动创建数据库表(如果已存在表,则会被删除)。
更改hibernate配置文件,添加mapping映射
<mapping class="com.daxingzsh.po.Student"/> <mapping class="com.daxingzsh.po.Classes"/>
四.测试代码:
package com.daxingzsh.test; import java.util.List; import junit.framework.TestCase; import org.hibernate.Criteria; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; import org.hibernate.criterion.Restrictions; import org.junit.Test; import com.daxingzsh.po.Classes; import com.daxingzsh.po.Student; public class MyTest extends TestCase{ private SessionFactory sessionFactory; private Session session; @Override protected void setUp() throws Exception { System.out.println("init ..."); sessionFactory = new Configuration().configure().buildSessionFactory(); } @Override protected void tearDown() throws Exception { if(sessionFactory != null) sessionFactory.close(); } @Test public void testSearch(){ test(); session = sessionFactory.openSession(); session.beginTransaction(); Criteria cri = session.createCriteria(Student.class); cri.createAlias("classes", "c1"); cri.add(Restrictions.eq("c1.className", "class1")); List<Student> list = cri.list(); for(Student st : list){ System.out.println(st.toString()); } // Criteria cri2 = cri.createCriteria("classes"); // cri2.add(Restrictions.eq("className", "class1")); // List<Student> list1 = cri2.list(); // for(Student st : list1){ // System.out.println(st.toString()); // } session.getTransaction().commit(); session.close(); } // @Test public void test() { System.out.println("start....."); session = sessionFactory.openSession(); session.beginTransaction(); Student s = new Student(); s.setsName("daxin"); s.setsSex("男"); Classes classes = new Classes(); classes.setClassName("class1"); s.setClasses(classes); session.save(classes); session.save(s); session.getTransaction().commit(); session.close(); System.out.println("end ...."); } }
经过测试则表明hibernate已经配置好了。
特别说明:hibernate的最新版本已经更新到5.0。