One-way, many-to-one mapping of hibernate learning

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Description: This instance is implemented by mapping files and annotations in two ways. You can choose the right way according to your own needs.

Instance:

1. Project structure

2.pom.xml

<project xmlns= "http://maven.apache.org/POM/4.0.0" xmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance" xsi: schemalocation= "http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" > < Modelversion>4.0.0</modelversion><groupid>org.hibernate</groupid><artifactid> hibernate-manytoone</artifactid><version>0.0.1-snapshot</version><packaging>jar</ Packaging><properties><project.build.sourceencoding>utf-8</project.build.sourceencoding> </properties><dependencies><!--Junit--><dependency><groupid>junit</groupid ><artifactid>junit</artifactid><version>4.12</version><scope>test</scope    ></dependency><!--Hibernate--><dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-core</artifactId> <version>5.1.7.final</version></dependency ><!--MySQL--><dependency> <groupId>mysql</groupId> <artifactid>mysql-connector-java</ Artifactid> <version>5.1.42</version></dependency></dependencies></project>

3.grade.java

Package Org.hibernate.entity;import Javax.persistence.column;import Javax.persistence.entity;import Javax.persistence.generatedvalue;import Javax.persistence.id;import org.hibernate.annotations.genericgenerator;@ Entitypublic class Grade {@Id @generatedvalue (generator= "GID") @GenericGenerator (name= "gid", strategy= "native") private int gid;//class @column (length=100) private string gname;//class name private string gdesc;//description public Grade () {}public Grade ( String gname, String gdesc) {super (); this.gname = Gname;this.gdesc = Gdesc;} 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;}}

4.student.java

Package Org.hibernate.entity;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 Org.hibernate.annotations.cascade;import Org.hibernate.annotations.GenericGenerator; @Entitypublic class Student {@Id @generatedvalue (generator= "Sid") @ Genericgenerator (name= "Sid", strategy= "native") private int sid;//Science number @column (length=100) Private String sname;// Name @column (length=2) private String sex;//sex @manytoone (Fetch=fetchtype.eager) @Cascade (value= Org.hibernate.annotations.CascadeType.SAVE_UPDATE) @JoinColumn (name= "GID") private Grade grade;//belongs to class public Student () {}public Student (string sname, String sex, Grade Grade) {this.sname = Sname;this.sex = Sex;this.grade = Grade;} public int GetSID () {return SID;} public void Setsid (int sid) {this.sid = SID;} Public String Getsname () {return sname;} public void Setsname (Stringsname) {this.sname = sname;} Public String Getsex () {return sex;} public void Setsex (String sex) {this.sex = sex;} Public Grade Getgrade () {return Grade;} public void Setgrade (Grade Grade) {this.grade = Grade;}}

5.grade.hbm.xml

<?xml version= "1.0" encoding= "UTF-8"? ><! DOCTYPE hibernate-mapping public     "-//hibernate/hibernate mapping DTD 3.0//en"    "Http://www.hibernate.org/dtd /hibernate-mapping-3.0.dtd ">
6.student.hbm.xml
<?xml version= "1.0" encoding= "UTF-8"? ><! DOCTYPE hibernate-mapping public     "-//hibernate/hibernate mapping DTD 3.0//en"    "Http://www.hibernate.org/dtd /hibernate-mapping-3.0.dtd ">
7.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 ">
 8.testmanytoone.java 
 
Package Org.hibernate.test;import Org.hibernate.session;import Org.hibernate.sessionfactory;import Org.hibernate.transaction;import Org.hibernate.cfg.configuration;import Org.hibernate.entity.grade;import Org.hibernate.entity.student;import Org.junit.after;import Org.junit.before;import Org.junit.Test;public class Testmanytoone {private sessionfactory sessionfactory;private Session session;private Transaction transaction;@ Beforepublic void before () {//Create Sessionfactory Object sessionfactory = new Configuration (). Configure (). buildsessionfactory ();//Get Session Object session = Sessionfactory.opensession ();//Open transaction transaction = Session.begintransaction ();} @Afterpublic void After () {//COMMIT transaction Transaction.commit ();//close Sessionsession.close ();// Close Sessionfactorysessionfactory.close ();} @Testpublic void Testadd () {Grade Grade = new Grade ("Java Class One", "Java Application Development class"); Student student1 = new Student ("Zhang San", "male", grade); Student Student2 = new Student ("John Doe", "male", grade); Session.save (grade); Session.save (student1); session.sAve (Student2);} @Testpublic void Testquery () {Student Student = Session.get (Student.class, 1); System.out.println (Student.getsname () + "-" + student.getsex () + "-" + Student.getgrade (). Getgname () + "-" + student. Getgrade (). Getgdesc ());} @Testpublic void Testupdate () {Grade Grade = new Grade ("Java Class II", "Java Application Development Class II"); Student Student = Session.get (Student.class, 2); Student.setgrade (grade); Session.update (Student);} @Testpublic void Testdelete () {Student Student = Session.get (Student.class, 2); Session.delete (Student);}}
9. Preview of effects
9.1 Implementing the Testadd method
9.2 Implementing the Testquery method
9.3 Implementing the Testupdate method
9.4 Implementing the Testdelete method
Reference: http://www.imooc.com/video/8675
http://www.imooc.com/video/10089
One-way, many-to-one mapping of hibernate learning