Shulou(Shulou.com)06/01 Report--

Download the full set of files: hibernate-release-4.1.7.Final.zip

Directory structure

Under the Documentation folder are the development help documents

The Lib folder is the library used by the developer, and the required directory under this folder is the JAR file that must be imported at the time of development.

The Project folder is the project source file

Comparison of JDBC and Hibernate:

Initial configuration deployment of Hibernate:

1. Create a web project

two。 Add the jar package of Hibernate required for the response

3. Create a Java Bean business entity class

4. Create a configuration file for entity class mapping: * * .hbm.xml

5. Create a configuration file hibernate.cfg.xml for Hibernate

6. Create a test class to test whether the hibernate is configured successfully

Entity class: UserInfo.java

Public class UserInfo

{

Private int userid

Private String userName

Private String userPwd

Private Date birthday

/ / various get and set methods for attributes have been omitted

/ / create a constructor with id

Public UserInfo (int id)

{

This.userid=id

}

Public UserInfo (int userid, String userName, String userPwd, Date birthday)

{

Super ()

This.userid = userid

This.userName = userName

This.userPwd = userPwd

This.birthday = birthday

}

/ / A constructor without parameters is required.

Public UserInfo ()

{

}

}

Configuration file UserInfo.hbm.xml for entity class

(try to keep the configuration file in the same package as the entity class name for ease of management and entity class name.)

/ / the package package specifies the package of the entity class

/ / name specifies the entity class name table as the table name corresponding to the entity class in the database. If not specified, it is consistent with the class name.

/ / id identifies the field class=native identification of the primary key since the growth

/ / property specifies the field of the attribute. Column can specify the name of the corresponding field in the database. If not, it is consistent with the attribute name of the entity class.

Configuration file hibernate.cfg.xml for Hibernate

True

True

Org.hibernate.dialect.Oracle10gDialect

Oracle.jdbc.driver.OracleDriver

Jdbc:oracle:thin:@192.168.3.252:1521:orcl

Bam1

Bam1

Update

Test class Test.java

Add a piece of data:

Public static void add ()

{

/ / step 1: read the configuration file hibernamte.cfg.xml file of Hibernate

Configurationcon=new Configuration () .configure ()

/ / step 2: create a service registration builder object and load all configuration information through the configuration object

ServiceRegistryBuilderregbulider=newServiceRegistryBuilder () .applySettings (con.getProperties ()

/ / create a registration service

ServiceRegistryreg=regbulider.buildServiceRegistry ()

/ / step 3: create a session factory

SessionFactorysessionFactory=con.buildSessionFactory (reg)

/ / step 4: create a data manipulation session

Sessionsession=sessionFactory.openSession ()

/ / create an object

, /

UserInfohanhan=new UserInfo ()

Hanhan.setUserName ("hanhan313")

Hanhan.setUserPwd ("123")

Hanhan.setBirthday (new Date ())

/ *

/ / create things

Transactiontran=session.beginTransaction ()

/ / Save data

Session.save (hanhan)

/ / submit things

Tran.commit ()

/ / close the conversation

Session.close ()

}

Query a piece of data:

After the session reply is created

/ / query the user information of userinfo with id 10

UserInfouser=session.get (UserInfo.class,10)

Update a piece of data:

First, query the data.

UserInfo user=session.get (UserInfo.class,10)

After modifying the data of user

And then get the session reply.

Session.update (user)

Delete a piece of data:

When deleting data, wrap the id data that needs to be deleted into objects.

For example:

UserInfouser=new UserInfo ()

User.setUserId (10)

Session.delete (user); / / when deleted, the id in user will be automatically obtained for deletion.

The process of hibernate:

Principles that must be followed in persisting JAVA classes

1. Declare the access method (get/set) for the persistent field of the class, and Hibernate persists the JavaBeans-style properties.

2. Implement a default constructor so that Hibernate can instantiate the object using the Constructor.newInstance () method.

3. If it is a property of a collection type, its type must be defined as the interface of the collection, for example: List, Set

4. Provide an identification attribute (Identifier property), without which some functions will not work, such as cascading updates, session.saveOrUpdate ().

Status of the object:

Instantaneous (transient): there is no data corresponding to it in the database. If it exceeds the scope, it will be reclaimed by the JVM garbage collector. It is usually an object that comes out of new and is not associated with session.

Persistent: there is data in the database corresponding to it, which is currently associated with session, and the associated session is not closed and the transaction is not committed; the state of the persistent object changes, which will affect the database when the transaction commits (hibernate can detect it).

Detached: there is data in the database that corresponds to it, but there is currently no session associated with it; the state of the managed object changes and cannot be detected by hibernate.

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