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

Create a DAO for the Hacker News TopStories 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 MyTopStoriesDAO {
  //request specific data from Hacker News (String type is used for simplicity)
  @SqlQuery("SELECT  FROM TopStories WHERE  = :")
  String findBy(@Bind("") String );

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

Open a Connection to Hacker News

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

Connecting to HackerNews

The HackerNews API (powered by Firebase) is a public API that requires no authentication. You can connect and query data immediately without any credentials.

After setting the following connection properties, you are ready to connect:

• AuthScheme: Set this to None.

Example connection string:

Profile=C:\profiles\HackerNews.apip;AuthScheme=None

Built-in Connection String Designer

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

jdbc:api:Profile=C:\profiles\HackerNews.apip;AuthScheme=None

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\HackerNews.apip;AuthScheme=None");
MyTopStoriesDAO dao = dbi.open(MyTopStoriesDAO.class);

//do stuff with the DAO

dao.close();

Read Hacker News Data

With the connection open to Hacker News, simply call the previously defined method to retrieve data from the TopStories entity in Hacker News.

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

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