<?php
namespace OdooOfficeHelper;

use MagentoFrameworkAppResourceConnection;
/**
*
*/
class DbConnection
{
    /**
     * Define common connection
     * @var unknown
     */
    protected $_resource;
    protected $_dbConnection;

    protected function __construct(
        ResourceConnection $resource,
        )
    {
        # code...
        // Set common connection
        $this->_resource        = $resource;
        $this->_dbConnection    = $this->_resource->getConnection();
    }

    public function Trans(){
        try{
            // Start transaction
            $this->_dbConnection->beginTransaction();

            //........

            // Commit transaction
            $this->_dbConnection->commit();
        } catch (Exception $e) {
            // Rollback transaction
            $this->_dbConnection->rollBack();
        }
    }

}