Define a domain model class that represents database table structure:

package com.example.elec.domain;

import java.io.Serializable;
import java.util.Date;

public class DeviceLog implements Serializable {
    private String logId;
    private String deviceName;
    private Date logDate;
    private String description;
    
    // Accessor methods
    public String getLogId() { return logId; }
    public String getDeviceName() { return deviceName; }
    public Date getLogDate() { return logDate; }
    public String getDescription() { return description; }
    
    // Mutator methods
    public void setLogId(String id) { this.logId = id; }
    public void setDeviceName(String name) { this.deviceName = name; }
    public void setLogDate(Date date) { this.logDate = date; }
    public void setDescription(String desc) { this.description = desc; }
}

Configuring Hibernate Mapping File

Create XML mapping configuration for the domain class:

<?xml version='1.0' encoding='UTF-8'?>
<hibernate-mapping>
    <class name="com.example.elec.domain.DeviceLog" table="DEVICE_LOGS">
        <id name="logId" type="string">
            <column name="LOG_ID" length="50" not-null="true"/>
            <generator class="uuid"/>
        </id>
        
        <property name="deviceName" type="string">
            <column name="DEVICE_NAME" length="50"/>
        </property>
        
        <property name="logDate" type="java.util.Date"/>
        
        <property name="description" type="string">
            <column name="DESCRIPTION" length="500"/>
        </property>
    </class>
</hibernate-mapping>

Setting Up Hibernate Configuration

Configure databace connection properties:

<?xml version="1.0" encoding="UTF-8"?>
<hibernate-configuration>
    <session-factory>
        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="connection.url">jdbc:mysql://localhost:3306/device_logs</property>
        <property name="connection.username">root</property>
        <property name="connection.password">secure123</property>
        <property name="dialect">org.hibernate.dialect.MySQL5Dialect</property>
        <property name="hbm2ddl.auto">update</property>
        <property name="show_sql">true</property>
        <mapping resource="com/example/elec/domain/DeviceLog.hbm.xml"/>
    </session-factory>
</hibernate-configuration>

Testing the Persistence Layerr

Create a JUnit test to verify database operasions:

package com.example.test;

import com.example.elec.domain.DeviceLog;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.junit.Test;

import java.util.Date;

public class PersistenceTest {
    @Test
    public void testSaveLog() {
        Configuration config = new Configuration().configure();
        SessionFactory factory = config.buildSessionFactory();
        Session session = factory.openSession();
        
        Transaction tx = session.beginTransaction();
        
        DeviceLog log = new DeviceLog();
        log.setDeviceName("Temperature Sensor");
        log.setDescription("Initial calibration complete");
        log.setLogDate(new Date());
        
        session.save(log);
        tx.commit();
        session.close();
    }
}