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

Create a DAO for the LINE ReplyMessageDelivery 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 MyReplyMessageDeliveryDAO {
  //request specific data from LINE (String type is used for simplicity)
  @SqlQuery("SELECT DeliveredCount FROM ReplyMessageDelivery WHERE DeliveryDate = :deliveryDate")
  String findDeliveredCountByDeliveryDate(@Bind("deliveryDate") String deliveryDate);

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

Open a Connection to LINE

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

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

LINE API Profile Settings

The LINE Messaging API uses Channel Access Token authentication. To obtain a Channel Access Token:

1. Log in to the LINE Developers Console at https://developers.line.biz
2. Select your provider and open your Messaging API channel.
3. Navigate to the Messaging API tab.
4. Under Channel access token, click Issue to generate a long-lived token.
5. Copy the generated token.

After obtaining your Channel Access Token, set the following connection properties:

• AuthScheme: Set this to APIKey.

Set the following in the ProfileSettings connection property:

• APIKey: Set this to your LINE Channel Access Token.

Built-in Connection String Designer

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

jdbc:api:Profile=C:\profiles\LINE.apip;ProfileSettings='APIKey=your_channel_access_token;';AuthScheme=APIKey;

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\LINE.apip;ProfileSettings='APIKey=your_channel_access_token;';AuthScheme=APIKey;");
MyReplyMessageDeliveryDAO dao = dbi.open(MyReplyMessageDeliveryDAO.class);

//do stuff with the DAO

dao.close();

Read LINE Data

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

//disply the result of our 'find' method
String deliveredCount = dao.findDeliveredCountByDeliveryDate("20240115");
System.out.println(deliveredCount);

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