Getting Started with the ObjectStore Java Interface

ObjectStore Java Tutorial

The tutorial provides an overview of the basic concepts of the ObjectStore Java Interface. It uses an example application to show you how to define persistent classes and manipulate persistent objects. It also shows you how to develop and run applications that use the ObjectStore Java Interface. First time users of the ObjectStore Java Interface should consider reading the ObjectStore Java Tutorial before reviewing the demonstration programs. If you are using the ObjectStore Java Interface on Windows, you should consult Rapid Database Development first, and then see this tutorial.

Rapid Database Development

For new users on Windows platforms, this tutorial provides step by step instructions for how to use ObjectStore Database Designer and Component Wizard to quickly design your database and create the basic components required in any ObjectStore Java Interface application. After you work through the ObjectStore Database Designer and Component Wizard Tutorial, consult the ObjectStore Java Tutorial.

Demonstration Programs

Demonstration programs provide examples of how to use the ObjectStore Java Interface. Select the README file to learn what the program does and how to run it. Select the directory to display a list of the source files, which you can examine outside the browser. The best demonstration to start with is the simple applet hit counter. After that, try the basic example of using the ObjectStore Java Interface. Brief descriptions of all demos are after the following table.

README File	Directory That Contains the Demo
Simple applet hit counter	install_dir/COM/odi/demo/pcount
Basic example of using the ObjectStore Java Interface	install_dir/COM/odi/demo/people
Using a peer (COM.odi.coll) dictionary in a trading model for portfolios of securities	install_dir/COM/odi/demo/cport
Java/C++ programs that create and access objects	install_dir/COM/odi/demo/jcpp
Using the ODMG API for the trading model for portfolios of securities	install_dir/COM/odi/demo/odmgcport
Persistence-Capable version of Microsoft XML parser	install_dir/COM/odi/demo/xml
Storing shapes and images and using the abstract window toolkit (AWT)	install_dir/COM/odi/demo/OSDraw
Converting third-party libraries to be persistence-capable	install_dir/COM/odi/demo/collections
Querying ObjectStore utility (COM.odi.util) collections	install_dir/COM/odi/demo/query
Using multiple cooperating threads	install_dir/COM/odi/demo/threads
Using multiple segments in multiple databases, exporting objects	install_dir/COM/odi/demo/tracker
Using the utility (COM.odi.util) collections in the trading model for portfolios of securities	install_dir/COM/odi/demo/pport
Using a peer (COM.odi.coll) set collection in the trading model for portfolios of securities	install_dir/COM/odi/demo/qport
Controlling persistent representation of objects	install_dir/COM/odi/demo/rep
Using ObjectStore with the Remote Method Interface	install_dir/COM/odi/demo/rmi

Here are descriptions of the demo programs:

• Simple applet hit counter shows how to write a simple applet that uses ObjectStore. You can use this applet as a hit counter, such as those you see on Web pages that indicate the number of times that page has been visited. (install_dir/COM/odi/demo/pcount)

• Basic example of using ObjectStore stores some information about a few people and then retrieves the information and displays it. Additional information about this demo is in Chapter 2 of the user guide. (install_dir/COM/odi/demo/people)

• Using a peer (COM.odi.coll) dictionary in a trading model for portfolios of securities computes the "net asset value" of a portfolio as a function of time, This demo is the same as the pport demo except that it uses a dictionary collection provided by the ObjectStore peer collections (COM.odi.coll) facility while the pport program uses the vector and hash table utility collections (COM.odi.util) classes. (install_dir/COM/odi/demo/cport)

• Java/C++ programs that create and access objects is an example of how to use C++ classes in an ObjectStore Java program. (install_dir/COM/odi/demo/jcpp)

• Using the ODMG API for the trading model for portfolios of securities also computes the net asset value of a portfolio as a function of time, based on the changes in the prices of the securities in the portfolio. This demo is the same as the cport demo except that it uses the ODMG API provided with the Java interface to ObjectStore. It also demonstrates how to postprocess some java.sql types and shadow the JDK classes with postprocessed versions. (install_dir/COM/odi/demo/odmgcport)

• Persistence-Capable version of Microsoft XML parser shows how document objects can be stored in ObjectStore databases. This demo shows a simple database of employee records that are built on the XML document object model. (install_dir/COM/odi/demo/xml)

• Storing shapes and images and using the abstract window toolkit (AWT) uses ObjectStore to store instances of various shape and image classes in a database. These classes represent objects such as lines, rectangles, ovals, polygons, text, and images in any size or color. The program uses the AWT to create window frames, menu bars, nested menus, and dialog boxes. (install_dir/COM/odi/demo/OSDraw)

• Converting third-party libraries to be persistence-capable shows how to convert the freely available collections library written by Doug Lea. (install_dir/COM/odi/demo/collections)

• Querying ObjectStore utility (COM.odi.util) collections provides two programs for querying a database that stores information about customers. Each program uses the collection and query features in COM.odi.util. One version uses a B-tree-based Map to look up customers by telephone number. The other version supports ad hoc queries (queries supplied by users at run time) with indexes. (install_dir/COM/odi/demo/query)

• Using multiple cooperating threads illustrates the use of ObjectStore in multi-threaded applications where the threads cooperate, which means they belong to the same session. (install_dir/COM/odi/demo/threads)

• Using multiple segments in multiple databases, and exporting objects provides an example of features specific to the Java interface to ObjectStore, and not included in ObjectStore PSE or PSE Pro for Java. These features include using multiple databases, allocating in multiple segments, exporting objects, and recovering from deadlock. (install_dir/COM/odi/demo/tracker)

• Using utility (COM.odi.util) collections in the trading model for portfolios of securities also computes the net asset value of a portfolio as a function of time, based on the changes in the prices of the securities in the portfolio. This program is the same as the cport demo except that it uses the vector and hash table (COM.odi.util) utility collections while the cport program uses a dictionary from the ObjectStore COM.odi.coll peer collections. (install_dir/COM/odi/demo/pport)

• Using a peer (COM.odi.coll) set collection and peer queries in the trading model for portfolios of securities also models the trading of portfolios of securities. This program is the same as the cport demo except that it uses COM.odi.coll peer Set collections to represent aggregation and does look ups with queries, instead of with dictionary classes. (install_dir/COM/odi/demo/qport)

• Controlling persistent representation of objects shows that you do not need to store all instance variables; you can choose your own representation. (install_dir/COM/odi/demo/rep)

• Using ObjectStore with the Remote Method Interface shows the Personalization application using the Remote Method Interface. The rmi demo is the application that is described in the tutorial. (install_dir/COM/odi/demo/rmi)