Sep 01 Beg WebObjects

Volume Number: 17 (2001)
Issue Number: 09
Column Tag: Beginning WebObjects 5

Part 1 - Presenting WebObjects 5

by Emmanuel Proulx

Introduction & Installation

Preface

This new column deals with WebObjects 5. It is meant to be easy and fun to read. This column talks about developing a Web application using WebObjects 5, in Java. Originally, this column was a book, with hundreds of pages. It has been cut down a lot to accommodate space restrictions.

Those interested in learning to build Web applications using WebObjects 5 should read this column. The only prerequisite is being Java programmers of at least intermediate level.

Other knowledge is not necessary, although understanding HTML basics can help tremendously because WebObjects borrows many characteristics from this language. If you don't know HTML at all but you still want to learn WebObjects, just skip the paragraphs that talk about HTML. For your convenience, these are usually marked with the symbol <HTML>. You won't get into any trouble, but you will not understand how WebObjects works behind the scene.

The same thing goes with databases. While knowing databases and SQL isn't necessary, you have to have basic knowledge if you're going to read the sections about databases. Database software is necessary if you're going to try out WebObjects' database features. I tried to keep all of the database interfacing and programming contents in separate sections for convenience.

Note that someone who masters Java programming, client/server design, HTML and Web Design as well as databases and SQL will be able to learn WebObjects radically faster.

What Is WebObjects?

I started this new job and the job description was "Java Developer". I was expecting to use one of these Java IDEs like Visual Café or Visual Age. My new boss said, "No, here we use WebObjects". I had heard about that tool, but I didn't know it was a Java IDE. It wasn't.

WebObjects is an environment for developing interactive Web Sites. The Java language is being used to implement Server-side behavior; the client side is mostly HTML, not necessarily Java Applets or even JavaScript for that matter.

WebObjects is much more than that. If also falls into the Application Server category. What is that? In the past, a "Server" would consist of just a Database. Nowadays a Server can also handle distributed transactions, multi-tier architecture, load-balancing, business logic, Enterprise JavaBeans, and other concepts and technologies involving more advanced server-side intelligence. An environment that helps with the development and deployment of such complex Servers is called an Application Server.

WO consists of multiple tools that are tightly integrated.

Project Builder: lets you browse the source code and manage the project.
WebObjects Builder: lets you assemble a Web Page.
Enterprise Object Modeler: lets you connect your Web Application to a database.
Interface Builder: lets you create Java applications and applets that connect to the WebObjects server for executing business logic and database access.
Direct To Web: a wizard that creates a complete database-driven customizable Web application.
Direct To Java Client: a wizard that creates a complete database-driven customizable Java program or applet.
Monitor: a remote task monitoring and performance analysis utility.

Other smaller utilities like a ‘Diff' utility, debugging tools, etc.

Other modules are included, yet they are not visible:

Web Server Adaptor: plugs into your Web Server to connect it to WebObjects.
JDBC Database Adaptor: connects WebObjects to a database driver.
The frameworks, which are powerful programming libraries. They support the whole WebObjects system. We refer to them as the Foundation, WebObjects and Enterprise Object Frameworks. The preceding tools make use of the Frameworks, and even generate some code that uses them.

How do these tools work with each other? The Figure 1 illustrates their interactions.

Figure 1. Interactions between the tools

In a typical WebObjects application, the focus is the project file, which points to the different components of the application. The Project Builder manages this file. Then, to create the Web Components (Web pages), you usually run the WebObjects Builder program. When a component makes use of a database, you have to use a model to link the tables of the database to your system's objects. This model is created using the EO Modeler. To let a user connect to your site, you need a Web Server containing the WebObjects Adaptor. There's more on each of these parts later on.

Lastly, WebObjects also is an IDE for developing Cocoa and Carbon applications, but this column deals only with Web applications.

Installation Information

First you must know that there are two distinct packages that can be installed with WebObjects 5. Each has its own specific use and list of installed components.

Developer edition: Contains all the graphical tools and libraries. Used for the development environment. At the time this was written, only the Mac OS X would support the Developer Edition.
Deployment edition: contains only the deployment tools and the run-time libraries. Used for the deployment environment. Can be installed on top of the Developer edition on Mac OS X. The Deployment Edition is available for a variety of platforms.

This column generally talks about the Developer edition. The Deployment edition will be covered in a separate article.

To develop with WebObjects Developer Edition, you need a Mac OS X environment with at least 128 megabytes of RAM and 600 megabytes of hard disk space. That said, remember this golden rule: you never have enough RAM and hard disk space!

Once you're done with your development, you can deploy your application on either Mac OS X, Windows 2000, or Solaris.

You will also need a supported Web server. On the Mac OS X, the default server is Apache, and works great.

If speed doesn't matter that much to you, you can get any Web Server with CGI capability. Else, you have to get a Web Server compatible with either the NSAPI or WAI standards (Netscape's Web Servers), ISAPI (Microsoft's Web Servers) or Apache. Of course, select a Web Server that works on your deployment platform.

If you need to access a database, you want to use one that has a JDBC 2.0 driver. WebObjects comes bundled with an evaluation version of OpenBase. But on deployment platforms you may want to go for an industrial-strength database, like Oracle, Informix, Sybase, DB/2, etc. You can also connect to any ODBC-compliant database on Windows using the ODBC/JDBC bridge, but that would make things slower.

NOTE: Not many database products are available on Mac OS X, so you may want to purchase a complete version of OpenBase (www.openbase.com).

Installation

Pre-Installation Steps

It is very important to install your Web Server before you install WebObjects.

NOTE: if you already installed WebObjects and you want to install a Web Server afterward, the only issue is with the "cgi-bin" folder. WebObjects has already copied its required executables in a temporary "cgi-bin" folder. After setting up your Web Server, you will have to copy these executables in the new Web Server's "cgi-bin" folder (you will have to make one if there is none).

Also, it doesn't hurt to install your database software at this point if you don't have one already.

On Mac OS X, both Apache and OpenBase are installed by default.

To install WebObjects on any platform, you need to log on as the Administrator (or root) user. If you don't have Administrator (or root) access rights, it won't work at all.

On Mac OS X, you have to first enable the root user (which is blocked by default) and then to log on as the root user. To enable the root user, open folder /Applications/Utilities, and double-click on NetInfo Manager. Once NetInfo Manager is running, open menu Domain | Security | Enable Root User. You will be asked to enter a password for the root user. Now log off and log on again using ‘root' as the user name, and the password you set previously. You are now logged as the root user and ready to install. After the installation is finished, you may disable the root user by running NetInfo Manager again.

Installation Steps

Insert your WebObjects CD in your CD-ROM drive. Double-click on the new icon that shows up in the desktop. Now double-click on the icon marked WebObjects_X_Developer.mpkg. This will call the installation program. Then, follow the instructions in the wizard-like window.

The following notes are meant to help you along the way. Read them before starting the install:

The serial number is usually located on a sticker on the CD envelope.
Be sure to read carefully the License Agreement for the next two hours. ;-)
Most people should choose a Typical Install. The Typical Install includes everything except the following (generally unimportant) items:
The Japanese language support
The source code
At one point, the WebObjects installation program could ask you for your Web Server's "cgi-bin" folder and its "docs" folder. Check them out and write them down before you start the install.
This process takes a very long time - be patient.
You will need to restart your computer at the end of the install, so it's a good idea to save your data and close all programs before even starting it.

Patches

I recommend that you install the latest patches for all of these (if you use them):

WebObjects itself
The operating system
The Web server
Your database software

For the Mac OS X, updating to the latest patch is very easy. You can get all the patches by going to the System Preferences panel, in the category Software Update. You will find there a button "Update Now". Clicking on it will check all software versions against an online database of patches. It will propose updates when they are available. I suggest you apply all of them. At the time this article was written, there was one patch available, which fixes many bugs. Install it.

On other platforms, updating to the latest patch may require that you visit each vendor's Web site and check for patches there. That's it — you are now ready to enjoy your development environment.

I didn't cover the deployment installation here because it is a complex topic that deserves its own article.

The Find-A-Luv example

I designed this column to have a good balance of theory and examples. I took good care of the theory, but I didn't want to make tiny useless examples and toy-code I had seen too often. Also, I didn't want to just show how to use the wizards of WebObjects and leave you alone with the customization. I needed a real Web Application and I wanted to develop it from scratch, not using just the wizards...

So throughout this column, I will be developing, as the main example, always the same Web Application. It features a Web Site for an imaginary dating services company. This company's promise is to help find nothing less than the client's soul mate. But be forewarned: if you're looking for your soul mate, this column will not help you.

We will start small and we'll expand this example as we go along.

Web Development Alternatives

WebObjects is not alone. There's a lot of competition out there. Many tools offer interactive Web Site/Server-side processing and Application Server solutions. Let's digest a few of the most popular ones.

Competing Interactive Web Site Solutions

The first ever solution for that is the CGI (common gateway interface). This is the most primitive solution. CGI is not a product; it's a feature of your Web Server that lets you insert your own program in you Web Site. That program can receive the user's input, and outputs a new Web Page based on it. The main disadvantage of the CGI is that the HTML code and database access are encapsulated into the source code; this is not pretty nor is it easy to develop. The main advantage is that you don't have to buy software to use CGI programs since it's already in your Web Server. Just use any computer language and you're on your way.

Sun Microsystems' Java Servlets are based on the same idea as CGIs, except they are written in Java and use their own module (called Servlet Runner program) that adds on to the Web Server. They have similar advantages and disadvantages as CGIs except for the fact that certain Web Servers don't support Servlets natively. Or if they do, their quality leaves a lot to be desired. This is the reason why commercial third party Servlet Runner programs (like Allaire's JRun) are available.

Allaire's ColdFusion is a commercial product that lets you write HTML "templates". That is, you write your HTML like you would normally do for your Web Page, and then you add in the same file the logic that makes the page interactive. You can even link your page to the database in only a few steps. The advantage is that you can use an HTML graphical editor for most of the work, and then add the logic afterward. ColdFusion is easy to use and produces results fast (just like HTML does). The main problem with ColdFusion is that it's not a real computer language; you can quickly arrive at the limit of what it can do.

Microsoft's ASP (Active Server Pages) also relies on "templates". But the logic is coded with Visual Basic. The main advantage is, like ColdFusion, fast development and tools that let you create pages easily. The disadvantage is that ASP is not portable: you can only use it on Microsoft's Web Servers.

Sun Microsystems' JSP (Java Server Pages) is an important player. JSP is based on the same idea as ASP, but the logic is coded in Java.

Here's a grid that summarizes the different characteristics of these solutions:�

Alternatives	CGI	Servlets	ColdFusion
Characteristics

Comes with your	Yes	Some	No
Web Server

Uses templates	No	No	Yes

Logic and HTML in	No, HTML	No, HTML	No, code
separate files	in code	in ccde	in HTML

Flexibility of a	Yes	Yes	No
real language

Supports most	YES	Yes, with	Yes
Web Servers		Servlet
		Runner
		program

Uses Java	No	Yes	No

Alternatives	ASP/JSP	WebObjects
Characteristics

Comes with your Web Server	Some	No

Uses Templates	Yes	Yes

Logic and HTML in separate files	No, code in HTML	Yes

Flexibility of a real language	Yes	Yes

Supports most Web Servers	NO	Yes

Uses Java	JSP only	Yes

Competing Application Servers

When Sybase wanted to issue an application server, they decided not to reinvent the wheel. They put together a set of existing tools then integrated them. Their Enterprise Application Server (or EAServer) is composed of Sybase's Jaguar CTS (application server) and PowerDynamo (Web server). EAServer is integrated with development tools like PowerBuilder and PowerJ, but these come separately.

IBM's application server is called simply WebSphere Application Server (Standard Edition). It features Servlets and JSP, a Web Server, and integration with Visual Age for Java and WebSphere Studio — sold separately. The Advanced and Enterprise editions offer more features, like EJB, better performance, security and other advanced features.

The Oracle Application Server provides a basic set of features; Web Server (with Servlet and JSP support), EJB, a stable and scaleable environment for deploying Web applications. It is also integrated with Oracle's IDEs, Oracle Developer and JDeveloper.

BEA's WebLogic Server is an application servers that follows the J2EE standard to the letter. It features also Servlets and JSP for the dynamic HTML part, integrated with the most popular third-party IDEs. EJB, Java 2 Enterprise Edition and the latest standards are supported.

Here's a grid that summarizes the different characteristics of these solutions:�

Alternatives Characteristics
		Sybase	IBM	BEA
		EAServer	WebSphere	WebLogicServer


Uses J2EE/EJB	Yes	Yes	Yes

Works on Mac		No	No	No

Comes with an IDE and tools		No (separate)	No (separate)	No

Does distributed	Yes	Advanced	Yes
transactions,			Edition only
monitoring and
load balancing.

Alternatives
Characteristics	Oracle	WebObjects
		Application
		Server

Uses J2EE/EJB	Yes	No

Works on Mac		No	Yes

Comes with an IDE and Tools		No (separate)	Yes

Does distributed transactions, monitoring and load balancing		Yes	Yes

As I am writing this book, there are countless different application server packages on the market. I will not cover them all, but I am convinced that only WebObjects covers such a wide variety of tools and features. But in general, I have noticed that most of the other application servers are just a bunch of distinct tools put together. Many of these products are tied to a single Web server or database. On the other hand, WebObjects has fully integrated tools that work together as a whole and leverages whatever tools (Web Server, database) you already have. Its programming libraries and database tools are jewels and no other vendor offers similar tools. While WebObjects does not follow the J2EE specification, its proprietary nature enables Apple to provide easy-to-use RAD tools and many "value-added" features. Furthermore, WebObjects is the only application server available on the Mac OS X.

Emmanuel Proulx is a Course Writer, Author and Web Developer, working in the domain of Java Application Servers. He can be reached at emmanuelp@theglobe.com.

Software Updates via MacUpdate

Latest Forum Discussions

Go from lowly lizard to wicked Wyvern in...

Do you like questing, and do you like dragons? If not then boy is this not the announcement for you, as Loongcheer Game has unveiled Quest Dragon: Idle Mobile Game. Yes, it is amazing Square Enix hasn’t sued them for copyright infringement, but... | Read more »

Aether Gazer unveils Chapter 16 of its m...

After a bit of maintenance, Aether Gazer has released Chapter 16 of its main storyline, titled Night Parade of the Beasts. This big update brings a new character, a special outfit, some special limited-time events, and, of course, an engaging... | Read more »

Challenge those pesky wyverns to a dance...

After recently having you do battle against your foes by wildly flailing Hello Kitty and friends at them, GungHo Online has whipped out another surprising collaboration for Puzzle & Dragons. It is now time to beat your opponents by cha-cha... | Read more »

Pack a magnifying glass and practice you...

Somehow it has already been a year since Torchlight: Infinite launched, and XD Games is celebrating by blending in what sounds like a truly fantastic new update. Fans of Cthulhu rejoice, as Whispering Mist brings some horror elements, and tests... | Read more »

Summon your guild and prepare for war in...

Netmarble is making some pretty big moves with their latest update for Seven Knights Idle Adventure, with a bunch of interesting additions. Two new heroes enter the battle, there are events and bosses abound, and perhaps most interesting, a huge... | Read more »

Make the passage of time your plaything...

While some of us are still waiting for a chance to get our hands on Ash Prime - yes, don’t remind me I could currently buy him this month I’m barely hanging on - Digital Extremes has announced its next anticipated Prime Form for Warframe. Starting... | Read more »

If you can find it and fit through the d...

The holy trinity of amazing company names have come together, to release their equally amazing and adorable mobile game, Hamster Inn. Published by HyperBeard Games, and co-developed by Mum Not Proud and Little Sasquatch Studios, it's time to... | Read more »

Amikin Survival opens for pre-orders on...

Join me on the wonderful trip down the inspiration rabbit hole; much as Palworld seemingly “borrowed” many aspects from the hit Pokemon franchise, it is time for the heavily armed animal survival to also spawn some illegitimate children as Helio... | Read more »

PUBG Mobile teams up with global phenome...

Since launching in 2019, SpyxFamily has exploded to damn near catastrophic popularity, so it was only a matter of time before a mobile game snapped up a collaboration. Enter PUBG Mobile. Until May 12th, players will be able to collect a host of... | Read more »

Embark into the frozen tundra of certain...

Chucklefish, developers of hit action-adventure sandbox game Starbound and owner of one of the cutest logos in gaming, has released their roguelike deck-builder Wildfrost. Created alongside developers Gaziter and Deadpan Games, Wildfrost will... | Read more »

Price Scanner via MacPrices.net

New today at Apple: Series 9 Watches availabl...

Apple is now offering Certified Refurbished Apple Watch Series 9 models on their online store for up to $80 off MSRP, starting at $339. Each Watch includes Apple’s standard one-year warranty, a new... Read more

The latest Apple iPhone deals from wireless c...

We’ve updated our iPhone Price Tracker with the latest carrier deals on Apple’s iPhone 15 family of smartphones as well as previous models including the iPhone 14, 13, 12, 11, and SE. Use our price... Read more

Boost Mobile will sell you an iPhone 11 for $...

Boost Mobile, an MVNO using AT&T and T-Mobile’s networks, is offering an iPhone 11 for $149.99 when purchased with their $40 Unlimited service plan (12GB of premium data). No trade-in is required... Read more

Free iPhone 15 plus Unlimited service for $60...

Boost Infinite, part of MVNO Boost Mobile using AT&T and T-Mobile’s networks, is offering a free 128GB iPhone 15 for $60 per month including their Unlimited service plan (30GB of premium data).... Read more

$300 off any new iPhone with service at Red P...

Red Pocket Mobile has new Apple iPhones on sale for $300 off MSRP when you switch and open up a new line of service. Red Pocket Mobile is a nationwide MVNO using all the major wireless carrier... Read more

Clearance 13-inch M1 MacBook Airs available a...

Apple has clearance 13″ M1 MacBook Airs, Certified Refurbished, available for $759 for 8-Core CPU/7-Core GPU/256GB models and $929 for 8-Core CPU/8-Core GPU/512GB models. Apple’s one-year warranty is... Read more

Updated Apple MacBook Price Trackers

Our Apple award-winning MacBook Price Trackers are continually updated with the latest information on prices, bundles, and availability for 16″ and 14″ MacBook Pros along with 13″ and 15″ MacBook... Read more

Every model of Apple’s 13-inch M3 MacBook Air...

Best Buy has Apple 13″ MacBook Airs with M3 CPUs in stock and on sale today for $100 off MSRP. Prices start at $999. Their prices are the lowest currently available for new 13″ M3 MacBook Airs among... Read more

Sunday Sale: Apple iPad Magic Keyboards for 1...

Walmart has Apple Magic Keyboards for 12.9″ iPad Pros, in Black, on sale for $150 off MSRP on their online store. Sale price for online orders only, in-store price may vary. Order online and choose... Read more

Apple Watch Ultra 2 now available at Apple fo...

Apple has, for the first time, begun offering Certified Refurbished Apple Watch Ultra 2 models in their online store for $679, or $120 off MSRP. Each Watch includes Apple’s standard one-year warranty... Read more

Jobs Board

DMR Technician - *Apple* /iOS Systems - Haml...

…relevant point-of-need technology self-help aids are available as appropriate. ** Apple Systems Administration** **:** Develops solutions for supporting, deploying, Read more

Omnichannel Associate - *Apple* Blossom Mal...

Omnichannel Associate - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Read more

Operations Associate - *Apple* Blossom Mall...

Operations Associate - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Read more

Cashier - *Apple* Blossom Mall - JCPenney (...

Cashier - Apple Blossom Mall Location:Winchester, VA, United States (https://jobs.jcp.com/jobs/location/191170/winchester-va-united-states) - Apple Blossom Mall Read more

IT Systems Engineer ( *Apple* Platforms) - S...

IT Systems Engineer ( Apple Platforms) at SpaceX Hawthorne, CA SpaceX was founded under the belief that a future where humanity is out exploring the stars is Read more

SPREAD THE WORD:
Slashdot
Digg
Del.icio.us
Reddit
Newsvine

MacTech