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

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

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

     About RabbitMQ Management HTTP API

     RabbitMQ is an open-source message broker that supports multiple messaging protocols. The RabbitMQ Management HTTP API provides HTTP-based access to management and monitoring data for a RabbitMQ server. The API exposes information about virtual hosts, exchanges, queues, bindings, connections, channels, consumers, users, permissions, policies, and cluster-wide statistics.

     The Management plugin must be enabled on the RabbitMQ server for the HTTP API to be available. By default, the management interface listens on port 15672.

     Using Basic Authentication

     RabbitMQ Management HTTP API uses HTTP Basic authentication. You must supply the username and password of a RabbitMQ management user.

     To enable access to the management API:

     1. Ensure the RabbitMQ Management plugin is enabled on your server (rabbitmq-plugins enable rabbitmq_management).
     2. Use an existing management user or create one with the appropriate management tag (management, policymaker, monitoring, or administrator).
     3. Note the full base URL of your RabbitMQ Management HTTP API (e.g., http://localhost:15672).

     After configuring your RabbitMQ server, set the following connection properties to connect:

     • AuthScheme: Set this to Basic.
     • URL: Set this to the base URL of your RabbitMQ Management HTTP API (e.g., http://localhost:15672).
     • User: Set this to your RabbitMQ management username (e.g., guest).
     • Password: Set this to your RabbitMQ management password.

     Example connection string:

     Profile=C:\profiles\RabbitMQ.apip;AuthScheme=Basic;URL=http://localhost:15672;User=guest;Password=guest;
     

     Available Tables

     The RabbitMQ profile provides access to the following tables:

     • Overview - Cluster-wide statistics and information about the RabbitMQ node
     • Nodes - Information about individual nodes in the RabbitMQ cluster
     • NodeMemory - Detailed memory usage breakdown for a specific cluster node
     • Connections - List of all open AMQP connections to the broker
     • Channels - List of all open AMQP channels across all connections
     • Consumers - List of all consumers registered across all queues
     • Exchanges - List of exchanges declared across all virtual hosts
     • Queues - List of queues declared across all virtual hosts
     • Bindings - List of all bindings between exchanges and queues
     • VirtualHosts - List of virtual hosts configured on the broker
     • VhostPermissions - User permissions within a specific virtual host
     • Users - List of all RabbitMQ users
     • Permissions - Permission records for all users across all virtual hosts
     • TopicPermissions - Topic-level permission records for all users
     • Policies - List of policies applied to queues and exchanges in virtual hosts
     • OperatorPolicies - List of operator policies applied to queues in virtual hosts
     • Parameters - List of component parameters (e.g., federation, shovel) per virtual host
     • GlobalParameters - List of global parameters that apply across all virtual hosts
     • VhostLimits - Resource limits configured for specific virtual hosts
     • UserLimits - Resource limits configured for specific users
     • FeatureFlags - List of feature flags and their enabled/disabled state on the node
     • DeprecatedFeatures - List of deprecated features and their usage state
     • AuthAttempts - Authentication attempt statistics for the node
     • ClusterName - The name of the RabbitMQ cluster
     • WhoAmI - Information about the currently authenticated management user
     • ExchangeBindingsSource - Bindings for which a specific exchange is the source
     • ExchangeBindingsDestination - Bindings for which a specific exchange is the destination
     • QueueBindings - Bindings for a specific queue within a virtual host

     Built-in Connection String Designer

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

     java -jar cdata.jdbc.api.jar
     

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

     

     A typical JDBC URL is below:

     jdbc:api:Profile=C:\profiles\\RabbitMQ.apip;AuthScheme=Basic;URL=http://localhost:15672;User=guest;Password=guest;

Connect Hibernate to RabbitMQ 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 RabbitMQ 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 RabbitMQ 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:

  
    
      cdata.api.APIDriver
    
    
      jdbc:api:Profile=C:\profiles\\RabbitMQ.apip;AuthScheme=Basic;URL=http://localhost:15672;User=guest;Password=guest;
    
    
      org.hibernate.dialect.SQLServerDialect
    
    
     
    

Execute SQL

Using the entity you created from the last step, you can now search RabbitMQ 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 AuthAttempts A WHERE NodeName = :NodeName";
    Query q = session.createQuery(SELECT, AuthAttempts.class);
    q.setParameter("NodeName","rabbit@hostname");
    List<AuthAttempts> resultList = (List<AuthAttempts>) q.list();

    for(AuthAttempts s: resultList){
      System.out.println(s.get());
      System.out.println(s.get());
    }
  }
}