Ready to get started?

Learn more about the CData JDBC Driver for HPCC or download a free trial:

Download Now

Create a Data Access Object for HPCC Systems Data using JDBI

A brief overview of creating a SQL Object API for HPCC Systems data in 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 HPCC Systems integrates connectivity to live HPCC Systems data in Java applications. By pairing these technologies, you gain simple, programmatic access to HPCC Systems data. This article walks through building a basic Data Access Object (DAO) and the accompanying code to read HPCC Systems data.

Create a DAO for the HPCC Systems hpcc::test::orders 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 Myhpcc::test::ordersDAO { //request specific data from HPCC Systems (String type is used for simplicity) @SqlQuery("SELECT Price FROM hpcc::test::orders WHERE ShipCity = :shipCity") String findPriceByShipCity(@Bind("shipCity") String shipCity); /* * close with no args is used to close the connection */ void close(); }

Open a Connection to HPCC Systems

Collect the necessary connection properties and construct the appropriate JDBC URL for connecting to HPCC Systems.

To connect, set the following connection properties: Set URL to the machine name or IP address of the server and the port the server is running on, for example, https://server:port. The User and Password are required to authenticate to the HPCC Systems cluster specified in the URL. Note that LDAP authentication is not currently supported by our ODBC driver.

Set Version to the WsSQL Web server version. Note that if you have not already done so, you will need to install the WsSQL service on the HPCC Systems server. The WsSQL Web service is used to interact with the underlying HPCC Systems platform.

Set Cluster to the target cluster.

Built-in Connection String Designer

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

java -jar cdata.jdbc.hpcc.jar

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

A connection string for HPCC Systems will typically look like the following:

jdbc:hpcc:URL=http://127.0.0.1:8510;User=test;password=xA123456;Version=1;Cluster=hthor;

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:hpcc:URL=http://127.0.0.1:8510;User=test;password=xA123456;Version=1;Cluster=hthor;"); Myhpcc::test::ordersDAO dao = dbi.open(Myhpcc::test::ordersDAO.class); //do stuff with the DAO dao.close();

Read HPCC Systems Data

With the connection open to HPCC Systems, simply call the previously defined method to retrieve data from the hpcc::test::orders entity in HPCC Systems.

//disply the result of our 'find' method String price = dao.findPriceByShipCity("New York"); System.out.println(price);

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