Collection-Mode component mappings

Scene: A student, there are contacts (contact name and contact details), a student can have more than one contact, storage is divided into two tables, a student table student, a Contact table, but only one configuration file, That is, a configuration file generates two tables, which is a one-to-many relationship and can be configured using a One-to-many mapping, with two configuration files, but here's an introduction to using the collection-mode component mappings or recommending the use of the former, because the former is intuitive and easy to understand

Contact.java

Package com.fgh.hibernate;

/**
 *	Contact Human
 * @author FGH
 *
 *
/public class Contacts {

	//Contact Way
	private String method;
	Contact Content
	private String name;

	Public String GetMethod () {return method
		;
	}

	public void Setmethod (String method) {
		This.method = method;
	}

	Public String GetName () {return
		name;
	}

	public void SetName (String name) {
		this.name = name;
	}

}

Student.java

Package com.fgh.hibernate;

Import Java.util.HashSet;
Import Java.util.Set;

/** *
 Student class
 * @author fgh
 * */public
class Student {

	//Because only one. hbm.xml configuration file is used, so here's the definition of Student_ Component The foreign key of the table
	private String student_id;

	Private String ID;

	private String name;
	
	Define a contact set for storing multiple contacts
	private Set contacts = new Hashset<contact> ();

	Public String GetId () {return
		ID;
	}

	public void SetId (String id) {
		this.id = ID;
	}

	Public String GetName () {return
		name;
	}

	public void SetName (String name) {
		this.name = name;
	}

	Public String getstudent_id () {return
		student_id;
	}

	public void setstudent_id (String student_id) {
		this.student_id = student_id;
	}

	Public Set getcontacts () {return
		contacts;
	}

	public void Setcontacts (Set contacts) {
		this.contacts = contacts;
	}

}

Student.hbm.xml

<?xml version= "1.0"?>
<! DOCTYPE hibernate-mapping public
        "-//hibernate/hibernate mapping DTD 3.0//en"
        "http:// Hibernate.sourceforge.net/hibernate-mapping-3.0.dtd ">

 

To build a table class:

Createtable.java


Package com.fgh.hibernate;

Import org.hibernate.cfg.Configuration;
Import Org.hibernate.tool.hbm2ddl.SchemaExport;

public class CreateTable {public

	static void Main (string[] args) {
		Schemaexport export = new Schemaexport (New Con Figuration (). Configure ());
		Export.create (True, true);
	}

 

Test class: Hibernatetest.java


Package com.fgh.hibernate;
Import org.hibernate.Session;
Import Org.hibernate.SessionFactory;
Import org.hibernate.Transaction;

Import org.hibernate.cfg.Configuration; /** * Assembly mapping is somewhat similar to a single table mapping just to get a list of the fields in a table. * * @author FGH * */public class Hibernatetest {private St

	Atic sessionfactory sessionfactory;
		static {try {sessionfactory = new Configuration (). Configure (). Buildsessionfactory ();
		catch (Exception e) {e.printstacktrace ();
		} public static void Main (string[] args) {Session session = Sessionfactory.opensession ();

		Transaction tx = NULL;

			try {tx = Session.begintransaction ();
			Student Student = new Student ();

			Student.setname ("Zhangsan");
			Contact contacts = new Contact ();
			Contact.setmethod ("Telephone");

			Contact.setname ("1231241234");
			Contact Contact2 = new Contact ();
			Contact2.setmethod ("Address");

			Contact2.setname ("Beijing");
			Student.getcontacts (). Add (Contact); Student.getcontacts (). Add (contACT2);
			Session.save (student);

		Tx.commit ();
			catch (Exception e) {e.printstacktrace ();
			if (null!= tx) {tx.rollback ();
		finally {session.close ();
 }
	}
}
Over