Create a Data Access Object for Quaderno 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 Quaderno integrates connectivity to live Quaderno data in Java applications. By pairing these technologies, you gain simple, programmatic access to Quaderno data. This article explains how to build a basic Data Access Object (DAO) and the accompanying code to read Quaderno data.

Create a DAO for the Quaderno Coupons 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 MyCouponsDAO {
 //request specific data from Quaderno (String type is used for simplicity)
 @SqlQuery("SELECT Name FROM Coupons WHERE Code = :code")
 String findNameByCode(@Bind("code") String code);

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

Open a Connection to Quaderno

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

Start by setting the Profile connection property to the location of the Quaderno Profile on disk (e.g. C:\profiles\Quaderno.apip). Next, set the ProfileSettings connection property to the connection string for Quaderno (see below).

Quaderno API Profile Settings

Find your API Key in your Quaderno account under Developers > API Keys > Private Key. Your AccountName is the subdomain of your Quaderno URL.

Built-in Connection String Designer

For assistance in constructing the JDBC URL, use the connection string designer built into the Quaderno 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 connection string for Quaderno will typically look like the following:

jdbc:api:Profile=C:\profiles\Quaderno.apip;ProfileSettings='APIKey=your_api_key;AccountName=your_account_name';

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:api:Profile=C:\profiles\Quaderno.apip;ProfileSettings='APIKey=your_api_key;AccountName=your_account_name';");
MyCouponsDAO dao = dbi.open(MyCouponsDAO.class);

//do stuff with the DAO

dao.close();

Read Quaderno Data

With the connection open to Quaderno, simply call the previously defined method to retrieve data from the Coupons entity in Quaderno.

//disply the result of our 'find' method
String name = dao.findNameByCode("SUMMER2024");
System.out.println(name);

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