Create applications using ObjectDb and JPA in NetBeans

February 19, 2011

Introduction

I have been developing Java applications for a long time and the major difficulty was the coding part related to database manipulations. Recently I shifted to use Object-Relational Mapping through JPA. I have used TopLink, EclipseLink, and Hibernate. Although I could achieve the functionally I want with ease, the output was slower when compared to normal method of database connection with JDBC. Then I used some Object databases like neoDatis. They were quite faster, yet I was reluctant to proceed as most of them had their own standards and did not comply to JPA. Finally I found the ObjectDB, an Object database for Java which completely supports JPA.

This article demonstrates how to create a simple JAVA Standard application in NetBeans using ObjectDB and JPA. The demonstrated application uses JPA to store and retrieve objects of two entity classes from an Embedded ObjectDB. It will demonstrate the capabilities of ObjectDB and JPA, which include persisting objects, removing saved objects and retrieving persisted objects. For this tutorial, besides the Java JDK and the NetBeans IDE,you only need to download
and extract the ObjectDB distribution zip file.The distribution zip contains everything necessary without any external dependency.

This tutorial consists of the following steps

Step 1: Create an ObjectDB Enabled Java SE Project
Step 2: Define a JPA Entity Classes
Step 3: Add a Main Class
Step 4: Design a Graphical User Interface
Step 5: Code user-defined Methods
Step 6: Code Events of Controls
Step 7: Run the program

Step 1: Create an ObjectDB Enabled Project

We start by creating a new NetBeans Project.

From the menu, select File > New to get the [New Project] dialog box

Select Java from Categories and
Java Application from Projects and click Next

Choose a Project Name (e.g City

Set the name of the Main class to main.Main – This will create a package named main and a Java Class named Main with the public static void main(String[] args){}

Click Finish to create the project.

Then ObjectDB/JPA support has to be added to the project

Download the ObjectDB installation files from the download page. The downloaded file, objectdb-(version).zip file has to be extracted to a folder like D:\Program Files\ObjectDB.

Find the project in Project window.If project window is not visible, press ctrl + 1 to get the project window. Right click on the project to get the popup menu and select the Properties to get the [Project Properties] window.

Click on Libraries under categories of the Project Properties Window. No libraries are listed at the moment under Compile tab.