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

Create a DAO for the Facebook Posts 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 MyPostsDAO {
 //insert new data into Facebook
 @SqlUpdate("INSERT INTO Posts (Target, LikesCount) values (:target, :likesCount)")
 void insert(@Bind("target") String target, @Bind("likesCount") String likesCount);

 //request specific data from Facebook (String type is used for simplicity)
 @SqlQuery("SELECT LikesCount FROM Posts WHERE Target = :target")
 String findLikesCountByTarget(@Bind("target") String target);

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

Open a Connection to Facebook

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

Most tables require user authentication as well as application authentication. Facebook uses the OAuth authentication standard. To authenticate to Facebook, you can use the embedded OAuthClientId, OAuthClientSecret, and CallbackURL or you can obtain your own by registering an app with Facebook.

See the Getting Started chapter of the help documentation for a guide to using OAuth.

Built-in Connection String Designer

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

java -jar cdata.jdbc.facebook.jar

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

A connection string for Facebook will typically look like the following:

jdbc:facebook:InitiateOAuth=GETANDREFRESH;

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:facebook:InitiateOAuth=GETANDREFRESH;");
MyPostsDAO dao = dbi.open(MyPostsDAO.class);

//do stuff with the DAO

dao.close();

Read Facebook Data

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

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

Write Facebook Data

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

//add a new entry to the Posts entity
dao.insert(newTarget, newLikesCount);

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