The integration of Java RMI (Remote Method Invocation) with Apache Kylin allows for seamless communication between the Apache Kylin OLAP (Online Analytical Processing) engine and Java applications. By leveraging RMI, developers can query, analyze, and visualize data stored in Kylin cubes from their Java applications.

To integrate RMI with Apache Kylin, follow these steps:

Step 1: Setting up Apache Kylin

First, make sure you have Apache Kylin installed and running. Set up Kylin cubes based on your data requirements, and ensure they are in a ready state for querying.

Step 2: Defining RMI Interface

Next, define the RMI interface that will be used for communication between the Java application and Apache Kylin. This interface should include methods for querying data from Kylin cubes, retrieving query results, and any other relevant operations.

public interface KylinService extends Remote {
    List<QueryResult> queryKylinCube(String cubeName, String query) throws RemoteException;
    
    // Other methods
}

Step 3: Implementing RMI Server

Implement the RMI server that will handle requests from Java applications and interact with Apache Kylin. The server should implement the defined RMI interface.

public class KylinRMIServer {
    public static void main(String[] args) throws RemoteException {
        try {
            LocateRegistry.createRegistry(Registry.REGISTRY_PORT);
            KylinService kylinService = new KylinServiceImpl(); // Your implementation of KylinService
            Naming.rebind("rmi://localhost/KylinService", kylinService);
            System.out.println("RMI server is listening...");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Step 4: Implementing RMI Client

Implement the RMI client that connects to the Apache Kylin RMI server and invokes the methods defined in the RMI interface.

public class KylinRMIClient {
    public static void main(String[] args) throws RemoteException {
        try {
            KylinService kylinService = (KylinService) Naming.lookup("rmi://localhost/KylinService");
            List<QueryResult> queryResults = kylinService.queryKylinCube("sales_cube", "SELECT * FROM sales");
            // Process query results
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Step 5: Querying Kylin Cubes

Once the RMI server and client are implemented and running, you can use the RMI client to query Kylin cubes. Provide the cube name and the SQL query as parameters to the queryKylinCube method. The method will return the query results as a list of QueryResult objects that can be processed by the Java application.

Conclusion

By integrating Java RMI with Apache Kylin, you can build powerful applications that leverage Kylin’s OLAP capabilities. This integration enables Java applications to query data stored in Kylin cubes and retrieve the results for analysis and visualization. RMI provides a straightforward communication mechanism between the application and Kylin, making it easier to build sophisticated data-driven applications. #JavaRMI #ApacheKylin