This article is primarily to be a component mapped in Hibernate, and you can refer to Chapter 7 of Hibernate official documentation. As for environmental settings, you can refer to the previous article.
Create a project
· New Java project: ComponentMapping, pay attention to "Create a separate source folder and output folder" while adding "user library": hibernate.
2. Write a class file
· Create a category, package name: javamxj.hibernate.component, class name: Person.
Person.java
/ *
* Hibernate - Component mapping
* Create a date 2005-4-10
* @author javamxj (sharing java happiness)
* @Link Blog: htpp: //javamxj.mblogger.cn
* htpp: //blog.9cbs.net/javamxj/
* /
Package javamxj.hibernate.component;
/ **
* @ hibernate.class
* /
Public class person {
Private long id;
PRIVATE STRING UserName;
Private address address;
/ **
* @ hibernate.id
* generator-class = "hilo"
* Unsaved-value = "null"
* /
Public long getId () {return id;}
Public void setid (long id) {this.id = id;}
/ **
* @ hibernate.property
* Length = "15"
* unique = "true"
* not-null = "true"
* /
Public string getUsername () {return username;}
Public void setusername (string username) {this.username = usrname;}
/ **
* @ hibernate.component
* /
Public Address getaddress () {return address;}
Public void setaddress (address address) {this.address = address;}
}
• The Person class calls the Address class, pay attention to the "@ hibernate.component" tag on the "GetDress ()" method.
• The Address class only contains some "@ hibernate.property" tags, and does not map its independent map into a table.
Address.java
Package javamxj.hibernate.component;
Public class address {
PRIVATE STRING Country;
PRIVATE STRING CITY;
PRIVATE STRING STREET;
PRIVATE STRING ZIPCODE;
Public address () {}
Public Address (String Country, String City, String Street, String Zipcode) {
Super ();
THIS.COUNTRY = Country; this.city = city;
THIS.STREET = STREET;
THIS.ZIPCODE = ZIPCODE;
}
/ **
* @ hibernate.property
* Length = "12"
* /
PUBLIC STRING GETCITY () {Return City;}
Public void setcity (string city) {this.city = city;}
/ **
* @ hibernate.property
* Length = "12"
* /
Public string getCountry () {return country;}
Public void setcountry (string country) {this.country = country;}
/ **
* @ hibernate.property
* Length = "6"
* /
Public String getzipcode () {return zipcode;}
Public void setzipcode (string number) {this.zipcode = Number;}
/ **
* @ hibernate.property
* Length = "12"
* /
Public string getStreet () {return street;}
Public void setstreet (string street) {this.street = street;
Public string toString () {
Return ("live in" country city "city" street "district"
"/ N / t Postal Code:" Zipcode);
}
}
3. Run the task
· Copy "
Eclipse quickly rapidly hibernate - 4. Inherited the build.xml in the article (1) "in the project directory.
· Double-click the "Generate-HBM" task, will find more animal.hbm.xml files in the package, there will be more hibernate.cfg.xml files in the src directory. If not, press the F5 button to refresh.
Person.hbm.xml
"- // Hibernate / Hibernate mapping DTD 2.0 // en"
"http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
>
Name = "javamxj.hibernate.component.Person"
Dynamic-update = "false"
Dynamic-insert = "false"
SELECT-Before-update = "false"
Optimistic-Lock = "Version"
>
Name = "id"
COLUMN = "ID"
TYPE = "java.lang.long" Unsaved-value = "null"
>
To Add Non xdoclet generator parameters, Create a file named
Hibernate-generator-params-person.xml
Containing the additional parameters and place it in your merge dir.
->
Name = "username"
TYPE = "java.lang.string"
Update = "true"
INSERT = "True"
Access = "Property"
Column = "username"
Length = "15"
NOT-NULL = "True"
Unique = "True"
/>
Name = "Address"
Class = "javamxj.hibernate.component.address"
>
Name = "city"
TYPE = "java.lang.string"
Update = "true"
INSERT = "True"
Access = "Property"
COLUMN = "city"
LENGTH = "12"
/>
Name = "country"
TYPE = "java.lang.string"
Update = "true"
INSERT = "True"
Access = "Property"
Column = "country"
LENGTH = "12"
/>
Name = "zipcode"
TYPE = "java.lang.string"
Update = "true"
INSERT = "True"
Access = "Property"
Column = "zipcode"
Length = "6"
/>
Name = "street"
TYPE = "java.lang.string"
Update = "true"
INSERT = "True"
Access = "Property"
COLUMN = "street"
LENGTH = "12"
/>
To Add Non XDoclet Property Mappings, Create A File Named
Hibernate-Properties-Person.xml
Containing The Additional Properties and Place It in Your Merge Dir .-->
· Run the MySQL server, then double-click the "SchemaExport" task, which will generate a "schema-export.sql" file in the project root directory.
Schema-export.sql
Drop Table if EXISTS PERSON
DROP TABLE IF EXISTS HIBERNATE_UNIQUE_KEY
CREATE TABLE PERSON
ID Bigint NOT NULL,
Username varchar (15) Not null unique,
City varchar (12),
Country varchar (12),
Zipcode Varchar (6),
Street varchar (12),
Primary Key (ID)
)
Create Table Hibernate_unique_Key
Next_hi integer
)
INSERT INTO Hibernate_unique_Key Values (0)
· Switch to the database, it will find that the data table is automatically generated.
5. Test procedure
● This time is different from the previous example. This time you enable a hibernateutil assisted class to manage Hibernate's session. This test class is relatively simple, you can refer to Chapter 1 of Hibernate official documentation.
· Create a new class, package name: javamxj.hibernate.util, class name: hibernateutil, code as follows:
Hibernateutil.java
Package javamxj.hibernate.util;
Import org.apache.commons.logging.log;
Import org.apache.commons.logging.logfactory;
Import net.sf.hibernate.hibernateException;
Import net.sf.hibernate.Session;
Import Net.sf.hibActory;
Import net.sf.hibernate.transaction;
Import Net.sf.hibiBernate.cfg.configuration;
Public class hibernateutil {
Private static log log = logfactory.getlog (HibernateUtil.class);
PRIVATE STATIC sessionFactory sessionFactory;
Private static final threadlocal threadsession = new threeReadlocal ();
Private static final threadlocal threadtransaction = new threadlocal ();
Public static sessionFactory getsessionFactory () {
IF (sessionFactory == NULL) {
Try {
// Create the sessionFactory
SessionFactory = new configuration (). configure ()
.BUILDSessionFactory ();
} catch (hibernateException ex) {ex.printstacktrace ();
Throw New RuntimeException ("Configuration Problem:"
ex.getMessage (), EX);
}
}
Return sessionFactory;
}
Public static session currentsession () throws hibernateException {
SESSION S = (session) threadsssion.get ();
// Open a new session, if this thread HAS NONE YET
IF (s == NULL) {
S = getsessionFactory (). OpenSession ();
Log.debug ("### Opening new session for this thread:" s);
Threadsession.Set (s);
} else {
Log.debug ("### session was existed:" s);
}
Return S;
}
Public static void closesession () THROWS HibernateException {
SESSION S = (session) threadsssion.get ();
Threadsession.Set (null);
IF (s! = null) {
Log.debug ("### closing session of this thread." s);
s.close ();
}
}
Public static void based begentransaction () throws hibernateException {
THREADTRANSACTION.GET ();
Try {
IF (tx == null) {
TX = currentsession (). Begintransaction ();
Log.debug ("### Starting New Database Transaction In this thread:" TX);
ThreadTransaction.Set (TX);
} else {
Log.debug ("### TX WAS EXISTED:" TX);
}
} catch (hibernateException ex) {
Throw EX;
}
}
Public static void committransaction () throws hibernateException {
THREADTRANSACTION.GET ();
Try {
IF (tx! = null &&! tx.wascommitted () &&! tx.wasrolledback ()) {
Log.debug ("### committing database transaction of this thread.");
TX.comMit ();
}
ThreadTransaction.Set (NULL);
} catch (hibernateException ex) {
RollbackTransaction ();
Throw EX;
}
}
Public static void rollbacktransaction () throws hibernateException {Transaction tx = (transaction) threadtransaction.get ();
Try {
ThreadTransaction.Set (NULL);
IF (tx! = null &&! tx.wascommitted () &&! tx.wasrolledback ()) {
Log.debug ("### Tyring to Rollback Database Transaction Of this Thread.");
TX.rollback ();
}
} catch (hibernateException ex) {
Throw EX;
} finally {
CloseSession ();
}
}
}
· Ok, then create a new ComponentDemo.java class under the package javamxj.hibernate.component.
ComponentDemo.java
Package javamxj.hibernate.component;
Import java.util.iterator;
Import java.util.list;
Import javamxj.hibernate.util.hibernateUtil;
Import net.sf.hibernate.hibernateException;
Import net.sf.hibernate.Session;
Public class componentdemo {
Public static void main (String [] args) {
Try {
New componentDemo ();
} catch (hibernateException he) {
HE.PrintStackTrace ();
}
}
Public ComponentDemo () throws hibernateException {
Session sess = hibernateutil.currents;
Person P = New Person ();
P.Setaddress (New Address ("China", "Shanghai", "Putuo", "200055");
P.SetuserName ("javamxj");
sess.save (p);
P = new person ();
P.Setaddress (New Address ("China", "Beijing", "Haidian", "100086"));
P.Setusername ("Zhang San");
sess.save (p);
List animals = sess.find ("from" person.class.getname ());
ITERATOR IT = Animals.Item (); it.hasnext ();) {
Person Person = (Person) IT.Next ();
System.out.println (Person.getuserName () ":" person.getaddress ());
}
Hibernateutil.closesis ();
}
}
· Run this class, the console output is as follows:
· At the same time, the following data is generated in the data sheet:
· The final project structure is as follows:
