Object-Relational Mapping (ORM) with HubDB Data Entities in Java

You can use Hibernate to map object-oriented domain models to a traditional relational database. The tutorial below shows how to use the CData JDBC Driver for HubDB to generate an ORM of your HubDB repository with Hibernate.

Though Eclipse is the IDE of choice for this article, the CData JDBC Driver for HubDB works in any product that supports the Java Runtime Environment. In the Knowledge Base you will find tutorials to connect to HubDB data from IntelliJ IDEA and NetBeans.

Install Hibernate

Follow the steps below to install the Hibernate plug-in in Eclipse.

1. In Eclipse, navigate to Help -> Install New Software.
2. Enter "http://download.jboss.org/jbosstools/neon/stable/updates/" in the Work With box.
3. Enter "Hibernate" into the filter box.
4. Select Hibernate Tools.

Start A New Project

Follow the steps below to add the driver JARs in a new project.

1. Create a new project. Select Java Project as your project type and click Next. Enter a project name and click Finish.
2. Right-click the project and click Properties. Click Java Build Path and then open the Libraries tab.
3. Click Add External JARs to add the cdata.jdbc.hubdb.jar library, located in the lib subfolder of the installation directory.

Add a Hibernate Configuration File

Follow the steps below to configure connection properties to HubDB data.

1. Right-click on the new project and select New -> Hibernate -> Hibernate Configuration File (cfg.xml).
2. Select src as the parent folder and click Next.

3. Input the following values:

   • Hibernate version:: 5.2
   • Database dialect: Derby
   • Driver class: cdata.jdbc.hubdb.HubDBDriver

   • Connection URL: A JDBC URL, starting with jdbc:hubdb: and followed by a semicolon-separated list of connection properties.

     There are two authentication methods available for connecting to HubDB data source: OAuth Authentication with a public HubSpot application and authentication with a Private application token.

     Using a Custom OAuth App

     AuthScheme must be set to "OAuth" in all OAuth flows. Be sure to review the Help documentation for the required connection properties for you specific authentication needs (desktop applications, web applications, and headless machines).

     Follow the steps below to register an application and obtain the OAuth client credentials:

     1. Log into your HubSpot app developer account.
        • Note that it must be an app developer account. Standard HubSpot accounts cannot create public apps.
     2. On the developer account home page, click the Apps tab.
     3. Click Create app.
     4. On the App info tab, enter and optionally modify values that are displayed to users when they connect. These values include the public application name, application logo, and a description of the application.
     5. On the Auth tab, supply a callback URL in the "Redirect URLs" box.
        • If you're creating a desktop application, set this to a locally accessible URL like http://localhost:33333.
        • If you are creating a Web application, set this to a trusted URL where you want users to be redirected to when they authorize your application.
     6. Click Create App. HubSpot then generates the application, along with its associated credentials.
     7. On the Auth tab, note the Client ID and Client secret. You will use these later to configure the driver.

     8. Under Scopes, select any scopes you need for your application's intended functionality.

        A minimum of the following scopes is required to access tables:

        • hubdb
        • oauth
        • crm.objects.owners.read
     9. Click Save changes.
     10. Install the application into a production portal with access to the features that are required by the integration.
         • Under "Install URL (OAuth)", click Copy full URL to copy the installation URL for your application.
         • Navigate to the copied link in your browser. Select a standard account in which to install the application.
         • Click Connect app. You can close the resulting tab.

     Using a Private App

     To connect using a HubSpot private application token, set the AuthScheme property to "PrivateApp."

     You can generate a private application token by following the steps below:

     1. In your HubDB account, click the settings icon (the gear) in the main navigation bar.
     2. In the left sidebar menu, navigate to Integrations > Private Apps.
     3. Click Create private app.
     4. On the Basic Info tab, configure the details of your application (name, logo, and description).
     5. On the Scopes tab, select Read or Write for each scope you want your private application to be able to access.
     6. A minimum of hubdb and crm.objects.owners.read is required to access tables.
     7. After you are done configuring your application, click Create app in the top right.
     8. Review the info about your application's access token, click Continue creating, and then Show token.
     9. Click Copy to copy the private application token.

     To connect, set PrivateAppToken to the private application token you retrieved.

     Built-in Connection String Designer

     For assistance in constructing the JDBC URL, use the connection string designer built into the HubDB JDBC Driver. Either double-click the JAR file or execute the jar file from the command-line.

     java -jar cdata.jdbc.hubdb.jar

     Fill in the connection properties and copy the connection string to the clipboard.

     A typical JDBC URL is below:

     jdbc:hubdb:AuthScheme=OAuth;OAuthClientID=MyOAuthClientID;OAuthClientSecret=MyOAuthClientSecret;CallbackURL=http://localhost:33333;InitiateOAuth=GETANDREFRESH

Connect Hibernate to HubDB Data

Follow the steps below to select the configuration you created in the previous step.

1. Switch to the Hibernate Configurations perspective: Window -> Open Perspective -> Hibernate.
2. Right-click on the Hibernate Configurations panel and click Add Configuration.
3. Set the Hibernate version to 5.2.
4. Click the Browse button and select the project.
5. For the Configuration file field, click Setup -> Use Existing and select the location of the hibernate.cfg.xml file (inside src folder in this demo).
6. In the Classpath tab, if there is nothing under User Entries, click Add External JARS and add the driver jar once more. Click OK once the configuration is done.
7. Expand the Database node of the newly created Hibernate configurations file.

Reverse Engineer HubDB Data

Follow the steps below to generate the reveng.xml configuration file. You will specify the tables you want to access as objects.

1. Switch back to the Package Explorer.
2. Right-click your project, select New -> Hibernate -> Hibernate Reverse Engineering File (reveng.xml). Click Next.
3. Select src as the parent folder and click Next.
4. In the Console configuration drop-down menu, select the Hibernate configuration file you created above and click Refresh.
5. Expand the node and choose the tables you want to reverse engineer. Click Finish when you are done.

Configure Hibernate to Run

Follow the steps below to generate plain old Java objects (POJO) for the HubDB tables.

1. From the menu bar, click Run -> Hibernate Code Generation -> Hibernate Code Generation Configurations.
2. In the Console configuration drop-down menu, select the Hibernate configuration file you created in the previous section. Click Browse by Output directory and select src.
3. Enable the Reverse Engineer from JDBC Connection checkbox. Click the Setup button, click Use Existing, and select the location of the hibernate.reveng.xml file (inside src folder in this demo).
4. In the Exporters tab, check Domain code (.java) and Hibernate XML Mappings (hbm.xml).
5. Click Run.

One or more POJOs are created based on the reverse-engineering setting in the previous step.

Insert Mapping Tags

For each mapping you have generated, you will need to create a mapping tag in hibernate.cfg.xml to point Hibernate to your mapping resource. Open hibernate.cfg.xml and insert the mapping tags as so:

Execute SQL

Using the entity you created from the last step, you can now search and modify HubDB data: import java.util.*; import org.hibernate.Session; import org.hibernate.cfg.Configuration; import org.hibernate.query.Query; public class App { public static void main(final String[] args) { Session session = new Configuration().configure().buildSessionFactory().openSession(); String SELECT = "FROM NorthwindProducts N WHERE Id = :Id"; Query q = session.createQuery(SELECT, NorthwindProducts.class); q.setParameter("Id","1"); List<NorthwindProducts> resultList = (List<NorthwindProducts>) q.list(); for(NorthwindProducts s: resultList){ System.out.println(s.getPartitionKey()); System.out.println(s.getName()); } } }