Create a Data Access Object for SAP HANA Data using JDBI

JDBI is a SQL convenience library for Java that exposes two different style APIs, a fluent style and a SQL object style. The CData JDBC Driver for SAP HANA integrates connectivity to live SAP HANA data in Java applications. By pairing these technologies, you gain simple, programmatic access to SAP HANA data. This article explains how to build a basic Data Access Object (DAO) and the accompanying code to read and write SAP HANA data.

Create a DAO for the SAP HANA Buckets Entity

The interface below declares the desired behavior for the SQL object to create a single method for each SQL statement to be implemented.

public interface MyBucketsDAO {
 //insert new data into SAP HANA
 @SqlUpdate("INSERT INTO Buckets (Name, OwnerId) values (:name, :ownerId)")
 void insert(@Bind("name") String name, @Bind("ownerId") String ownerId);

 //request specific data from SAP HANA (String type is used for simplicity)
 @SqlQuery("SELECT OwnerId FROM Buckets WHERE Name = :name")
 String findOwnerIdByName(@Bind("name") String name);

 /*
 * close with no args is used to close the connection
 */
 void close();
}

Open a Connection to SAP HANA

Collect the necessary connection properties and construct the appropriate JDBC URL for connecting to SAP HANA.

Set the Server, Database and Port properties to specify the address of your SAP Hana database to interact with. Set the User and the Password properties to authenticate to the server.

Built-in Connection String Designer

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

java -jar cdata.jdbc.saphana.jar

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

A connection string for SAP HANA will typically look like the following:

jdbc:saphana:User=system;Password=mypassword;Server=localhost;Database=systemdb;

Use the configured JDBC URL to obtain an instance of the DAO interface. The particular method shown below will open a handle bound to the instance, so the instance needs to be closed explicitly to release the handle and the bound JDBC connection.

DBI dbi = new DBI("jdbc:saphana:User=system;Password=mypassword;Server=localhost;Database=systemdb;");
MyBucketsDAO dao = dbi.open(MyBucketsDAO.class);

//do stuff with the DAO

dao.close();

Read SAP HANA Data

With the connection open to SAP HANA, simply call the previously defined method to retrieve data from the Buckets entity in SAP HANA.

//disply the result of our 'find' method
String ownerId = dao.findOwnerIdByName("TestBucket");
System.out.println(ownerId);

Write SAP HANA Data

It is also simple to write data to SAP HANA, using the previously defined method.

//add a new entry to the Buckets entity
dao.insert(newName, newOwnerId);

Since the JDBI library is able to work with JDBC connections, you can easily produce a SQL Object API for SAP HANA by integrating with the CData JDBC Driver for SAP HANA. Download a free trial and work with live SAP HANA data in custom Java applications today.