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

Create a DAO for the EnterpriseDB 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 MyOrdersDAO {
 //insert new data into EnterpriseDB
 @SqlUpdate("INSERT INTO Orders (ShipCountry, ShipCity) values (:shipCountry, :shipCity)")
 void insert(@Bind("shipCountry") String shipCountry, @Bind("shipCity") String shipCity);

 //request specific data from EnterpriseDB (String type is used for simplicity)
 @SqlQuery("SELECT ShipCity FROM Orders WHERE ShipCountry = :shipCountry")
 String findShipCityByShipCountry(@Bind("shipCountry") String shipCountry);

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

Open a Connection to EnterpriseDB

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

The following connection properties are required in order to connect to data.

• Server: The host name or IP of the server hosting the EnterpriseDB database.
• Port: The port of the server hosting the EnterpriseDB database.

You can also optionally set the following:

• Database: The default database to connect to when connecting to the EnterpriseDB Server. If this is not set, the user's default database will be used.

Connect Using Standard Authentication

To authenticate using standard authentication, set the following:

• User: The user which will be used to authenticate with the EnterpriseDB server.
• Password: The password which will be used to authenticate with the EnterpriseDB server.

Connect Using SSL Authentication

You can leverage SSL authentication to connect to EnterpriseDB data via a secure session. Configure the following connection properties to connect to data:

• SSLClientCert: Set this to the name of the certificate store for the client certificate. Used in the case of 2-way SSL, where truststore and keystore are kept on both the client and server machines.
• SSLClientCertPassword: If a client certificate store is password-protected, set this value to the store's password.
• SSLClientCertSubject: The subject of the TLS/SSL client certificate. Used to locate the certificate in the store.
• SSLClientCertType: The certificate type of the client store.
• SSLServerCert: The certificate to be accepted from the server.

Built-in Connection String Designer

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

java -jar cdata.jdbc.enterprisedb.jar

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

👁 Using the built-in connection string designer to generate a JDBC URL (Salesforce is shown.)

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

jdbc:enterprisedb:User=postgres;Password=admin;Database=postgres;Server=127.0.0.1;Port=5444

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:enterprisedb:User=postgres;Password=admin;Database=postgres;Server=127.0.0.1;Port=5444");
MyOrdersDAO dao = dbi.open(MyOrdersDAO.class);

//do stuff with the DAO

dao.close();

Read EnterpriseDB Data

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

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

Write EnterpriseDB Data

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

//add a new entry to the Orders entity
dao.insert(newShipCountry, newShipCity);

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