how to save creation and updation timestamp with hibernate.

 how to save creation and updation timestamp with hibernate.

for explnation watch the video :

Object time stamping feature of hibernate

=========================================

->this feature keeps track of the object/record is saved/inserted initially

later it also keeps track of when record/object is lastly updated/modified

=>Object versioning feature keeps track how many times the object/record is modified using

Hibernate persistence logic where Object timestampping feature keeps track when exactly the Object/record

is inserted and lastly updated.

useCases for timeStampping

==========================

->Keeping the track of when the password lastly changed

->keeping the track of when stock market share values lastly updated/modified

->Keeping the track of when last tx happend in the bank account

In annotation driven HB programming

====================================

->we can enable timestamp,version features at a time on single entity class

-> in timestamp feature we can take seperate col/property holding the object/record

insertion date and time and another seperate property holding object/record last updation

date and time

@CreationTimeStamp

@UpdationTimeStamp

Directory Structure

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>com.test</groupId>

<artifactId>Bank</artifactId>

<version>0.0.1-SNAPSHOT</version>

<packaging>jar</packaging>

<name>Bank</name>

<url>http://maven.apache.org</url>

<properties>

<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

<maven.compiler.source>1.9</maven.compiler.source>

<maven.compiler.target>1.9</maven.compiler.target>

</properties>

<dependencies>

<dependency>

<groupId>junit</groupId>

<artifactId>junit</artifactId>

<version>3.8.1</version>

<scope>test</scope>

</dependency>

<dependency>

<groupId>org.hibernate</groupId>

<artifactId>hibernate-core</artifactId>

<version>5.6.8.Final</version>

</dependency>

<!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->

<dependency>

<groupId>org.projectlombok</groupId>

<artifactId>lombok</artifactId>

<version>1.18.20</version>

<scope>provided</scope>

</dependency>

<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->

<dependency>

<groupId>mysql</groupId>

<artifactId>mysql-connector-java</artifactId>

<version>8.0.22</version>

</dependency>

</dependencies>

</project>

Entity class

Account.java

package com.test.entity;

import java.sql.Timestamp;

import javax.persistence.Entity;

import javax.persistence.Id;

import javax.persistence.Table;

import javax.persistence.Version;

import org.hibernate.annotations.CreationTimestamp;

import org.hibernate.annotations.UpdateTimestamp;

import lombok.AllArgsConstructor;

import lombok.Data;

import lombok.NoArgsConstructor;

@Data

@AllArgsConstructor

@NoArgsConstructor

@Entity

@Table(name = "acctab")

public class Account {

@Id

private String accId;

private String name;

private Double balance;

@Version

private Integer updationCount;//for versioning

@CreationTimestamp

private Timestamp creationTime;//holds record insertion time

@UpdateTimestamp

private Timestamp lastUpdationTime;//holds records lastUpdation time

public Account(String accId, String name, Double balance) {

super();

this.accId = accId;

this.name = name;

this.balance = balance;

}

}

Utility Class

HibernateUtil.java

package com.test.util;

import java.util.Properties;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.cfg.Configuration;

import org.hibernate.cfg.Environment;

import com.test.entity.Account;

public class HibernateUtil {

static SessionFactory factory = null;

static {

Configuration cfg = new Configuration();

Properties props = new Properties();

props.put(Environment.URL, "jdbc:mysql://localhost:3306/new");

props.put(Environment.USER, "root");

props.put(Environment.PASS, "root");

props.put(Environment.SHOW_SQL, true);

props.put(Environment.HBM2DDL_AUTO, "update");

props.put(Environment.FORMAT_SQL, true);

cfg.setProperties(props);

cfg.addAnnotatedClass(Account.class);

    factory = cfg.buildSessionFactory();

}

public static SessionFactory getSessionFactory() {

return factory;

}

public static Session getSession() {

return factory.openSession();

}

}

Save.java

======

package com.test;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import com.test.entity.Account;

import com.test.util.HibernateUtil;

public class Save {

public static void main(String[] args) {

//get the SessionFactory Object

SessionFactory factory = HibernateUtil.getSessionFactory();

//get the session object

Session ses = HibernateUtil.getSession();

try(factory;ses){

//create Object 

Account a1 = new Account("A1B1","SAM",5000.0);

Account a2 = new Account("A2B2","Jhon",6000.0);

Account a3 = new Account("A3B3","Brock",7000.0);

ses.beginTransaction();

ses.save(a1);

ses.save(a2);

ses.save(a3);

ses.getTransaction().commit();

}catch(Exception e) {

e.printStackTrace();

}

}

}

after running Save.java

table

Update.java

package com.test;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import com.test.entity.Account;

import com.test.util.HibernateUtil;

public class Update {

public static void main(String[] args) {

//get the SessionFactory Object

SessionFactory factory = HibernateUtil.getSessionFactory();

//get the session object

Session ses = HibernateUtil.getSession();

try(factory;ses){

//fetch the obj

Account a1 = ses.get(Account.class, "A1B1");

ses.beginTransaction();

a1.setBalance(4000.0);

ses.update(a1);

ses.getTransaction().commit();

System.out.println("Object is updated for "+a1.getUpdationCount());

System.out.println("Object is last updated at  "+a1.getLastUpdationTime());

}catch(Exception e) {

e.printStackTrace();

}

}

}

After running Update.java

table