Object-Relational Mapping (ORM) with Bitbucket 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 Bitbucket to generate an ORM of your Bitbucket repository with Hibernate.

Though Eclipse is the IDE of choice for this article, the CData JDBC Driver for Bitbucket works in any product that supports the Java Runtime Environment. In the Knowledge Base you will find tutorials to connect to Bitbucket 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.bitbucket.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 Bitbucket 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.bitbucket.BitbucketDriver

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

     For most queries, you must set the Workspace. The only exception to this is the Workspaces table, which does not require this property to be set, as querying it provides a list of workspace slugs that can be used to set Workspace. To query this table, you must set Schema to 'Information' and execute the query SELECT * FROM Workspaces>.

     Setting Schema to 'Information' displays general information. To connect to Bitbucket, set these parameters:

     • Schema: To show general information about a workspace, such as its users, repositories, and projects, set this to Information. Otherwise, set this to the schema of the repository or project you are querying. To get a full set of available schemas, query the sys_schemas table.
     • Workspace: Required if you are not querying the Workspaces table. This property is not required for querying the Workspaces table, as that query only returns a list of workspace slugs that can be used to set Workspace.

     Authenticating to Bitbucket

     Bitbucket supports OAuth authentication only. To enable this authentication from all OAuth flows, you must create a custom OAuth application, and set AuthScheme to OAuth.

     Be sure to review the Help documentation for the required connection properties for you specific authentication needs (desktop applications, web applications, and headless machines).

     Creating a custom OAuth application

     From your Bitbucket account:

     1. Go to Settings (the gear icon) and select Workspace Settings.
     2. In the Apps and Features section, select OAuth Consumers.
     3. Click Add Consumer.
     4. Enter a name and description for your custom application.
     5. Set the callback URL:
        • For desktop applications and headless machines, use http://localhost:33333 or another port number of your choice. The URI you set here becomes the CallbackURL property.
        • For web applications, set the callback URL to a trusted redirect URL. This URL is the web location the user returns to with the token that verifies that your application has been granted access.
     6. If you plan to use client credentials to authenticate, you must select This is a private consumer. In the driver, you must set AuthScheme to client.
     7. Select which permissions to give your OAuth application. These determine what data you can read and write with it.
     8. To save the new custom application, click Save.
     9. After the application has been saved, you can select it to view its settings. The application's Key and Secret are displayed. Record these for future use. You will use the Key to set the OAuthClientId and the Secret to set the OAuthClientSecret.

     Built-in Connection String Designer

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

     java -jar cdata.jdbc.bitbucket.jar

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

     A typical JDBC URL is below:

     jdbc:bitbucket:Workspace=myworkspaceslug;Schema=InformationInitiateOAuth=GETANDREFRESH

Connect Hibernate to Bitbucket 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 Bitbucket 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 Bitbucket 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 Bitbucket 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 Issues I WHERE Id = :Id"; Query q = session.createQuery(SELECT, Issues.class); q.setParameter("Id","1"); List<Issues> resultList = (List<Issues>) q.list(); for(Issues s: resultList){ System.out.println(s.getTitle()); System.out.println(s.getContentRaw()); } } }