Data not save in the database table

I created sample java project and try to save data with JPA. able to connect with the database as well as able to create the related database table(named laptop) as well as. But when i try to save data(Laptop object). Those data not in the database table(in laptop table)

persistence.xml file

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence
             http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd">
    <persistence-unit name="laptop_persist">
    <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
        <properties>
            <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
            <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/device_store"/>
            <property name="hibernate.connection.autocommit" value="false"/>
            <property name="hibernate.connection.username" value="root"/>
            <property name="hibernate.connection.password" value="19940306"/>
            <property name="hibernate.dialect" value="org.hibernate.dialect.MySQL5Dialect"/>
            <property name="hibernate.connection.CharSet" value="utf8"/>
            <property name="hibernate.connection.characterEncoding" value="utf8"/>
            <property name="hibernate.connection.useUnicode" value="true"/>
            <property name="hibernate.show_sql" value="false"/>
            <property name="hibernate.hbm2ddl.auto" value="update"/>
        </properties>
    </persistence-unit>
</persistence>

Laptop.java class

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import java.util.logging.Logger;

@Entity
@Table(name = "laptop")
public class Laptop implements Device {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long lapId;
    @Column(name = "brand_name")
    private String brandName;
    @Column(name = "model_name")
    private String modelName;
    @Column(name = "serial_number")
    private String serialNumber;

    public Laptop(String brandName, String modelName, String serialNumber) {
        this.brandName = brandName;
        this.modelName = modelName;
        this.serialNumber = serialNumber;
    }

    public Laptop() {
    }

    public String getBrandName() {
        return brandName;
    }

    public void setBrandName(String brandName) {
        this.brandName = brandName;
    }

    public String getModelName() {
        return modelName;
    }

    public void setModelName(String modelName) {
        this.modelName = modelName;
    }

    public String getSerialNumber() {
        return serialNumber;
    }

    public void setSerialNumber(String serialNumber) {
        this.serialNumber = serialNumber;
    }

    public Long getLapId() {
        return lapId;
    }

    public void start() {
        System.out.println("Starting the" + serialNumber + " laptop...");
    }

    public void restart() {
        System.out.println("restarting the laptop...");
    }

    public void shutdown() {
        System.out.println("Shutting down the laptop...");
    }
}

Main.java class

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;

public class Main {
    public static void main(String[] args) {
        Laptop laptop = new Laptop("aaa","bbb","cccc");
        EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("laptop_persist");
        EntityManager entityManager = entityManagerFactory.createEntityManager();
        entityManager.persist(laptop);
        entityManager.close();
        entityManagerFactory.close();
    }
}

pom.xml file

<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.example</groupId>
<artifactId>pc-hi</artifactId>
<version>1.0-SNAPSHOT</version>
<name>Archetype - pc-hi</name>
<url>http://maven.apache.org</url>

<dependencies>
  <dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.31</version>
  </dependency>
  <dependency>
    <groupId>org.hibernate</groupId>
    <artifactId>hibernate-core</artifactId>
    <version>5.5.7.Final</version>
  </dependency>
  <dependency>
    <groupId>org.testng</groupId>
    <artifactId>testng</artifactId>
    <version>6.9.6</version>
    <scope>test</scope>
  </dependency>
  <dependency>
    <groupId>org.slf4j</groupId>
    <artifactId>slf4j-api</artifactId>
    <version>1.7.5</version>
  </dependency>
</dependencies>
<build>
  <plugins>
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-compiler-plugin</artifactId>
      <configuration>
        <source>8</source>
        <target>8</target>
      </configuration>
    </plugin>
  </plugins>
</build>

As I mentioned in above, the laptop table has created. But unable to save the data

As you turn off auto-commit (i.e hibernate.connection.autocommit=false) which is a good practise for changing the data , you have to explicitly declare when to start and commit the transaction.

Change to the following should fix the issue :

entityManager.getTransaction().begin();
entityManager.persist(laptop);
entityManager.getTransaction().commit();