2007 - Eric Feminella

Cairngen 2.0

It has been awhile since the release of Cairngen 1.0, and the feedback I have received from the community has been very encouraging. I am happy to have provided a first-of-it’s-kind utility which allows developers to save time when building Flex applications on Adobe Cairngorm. Additionally, many of you have contacted me with some really cool new features that you have added, some of which are now available in this latest release.

Objective
The main objective of Cairngen 2.0 was to address 2 issues which were inherent to Cairngen 1.0. The first being that Event / Command mappings were not automated. In Cairngen 1.0 developers had the ability to generate sequences which consisted of an Event, Command and optional Business Delegate. And although this was very useful as it generated all of the required classes, handled upcasting events and instantiating Business Delegates, developers were still required to implement addCommand() in the FrontController manually. The second issue was that Event types were not generated as uppercase. Event types are static constants therefore they should always be uppercase. This is not required, however it is a best practice. Again developers could easily generate the required Event class but they would have to manually modify the event type to make it uppercase.

These two issues were the main thing preventing Cairngen from full circle code generation and implementation. Cairngen 2.0 addresses these 2 issues by automating the process, thus allowing for even faster development of Cairngorm projects.

So what’s new in Cairngen 2.0?

FrontController addCommand automation
Event / Command mappings via the FrontController are now automated. When generating a sequence (Event, Command, Business Delegate) the FrontController will be modified to implement an additional addCommand for the Event and Command. This is achieved by a simple //todo comment which is uses as a token and replaced when sequences are generated.

Event TYPE
Event type constants are now generated as upper case. Additionally the value of the event type is set to the fully qualified namespace of the event, thus preventing it from possible collisions with other Events.

User prompted before deleting
You will now be prompted prior to deleting directories in Cairngen 2.0. You can override this by setting the new “prompt.on.delete” property to false

Class file copyright header
Developers can add a specific copyright header for each class file generated. When specified the header will be added before the package definition.

Remote class VOs
The ability to generate and register remote classes with a VO is now available

Logging
Developers can toggle between logging the console output. This can be accomplished by setting the “log.output” property to true or false

What’s next?
I don’t know, you tell me? If you have additional features you would like to see added to Cairngen, or if you have extended Cairngen to provide these features, feel free to leave a comment on this page. I am planning on adding some new features in the near future. One of which will be the ability to detect duplicate addCommands.

I would like to thank the many developers who have contributed to the development of Cairngen 2.0. I am in the process of compiling a list of contributors, at which point I will update the release notes.

Cairngen is licensed under the MIT License.

Ant and Ant-contrib are licensed under The Apache Software License

Download Cairngen 2.0

November 15, 2007 News

6 Comments

Measuring code performance in ActionScript 3

Adobe Flex 3 introduces the much needed, and highly welcomed Flex Profiler which allows Flex and AIR application to be thoroughly examined to measure code performance and determine potential so called “memory leaks” (not that such a thing exists – it’s called a programming error, but that’s a whole other subject in itself). Flex 3.0 provides a new profiling perspective which contains all of the tools one might expect from a high quality profiling utility. I highly recommend taking advantage of the profiler and utilizing it as a powerful addition to your Flex workflow.

Even with all of the great features available in the Profiler I still find it useful to have the ability to monitor code performance in ActionScript, especially when determining the elapsed duration of service invocations. With this in mind I developed a simple API which allows developers to measure the performance of their code as it executes; such as loops, method invocations, service invocations and so forth.

The Execution class provides an intuitive API (defined by IExecutable) from which the elapsed time of a code execution, as well as the total duration of a code execution can be measured. This can be accomplished in as little as 2 lines of code. The underlying implementation is simple and the higher level API makes it easy to use.

Typically developers should utilize the Execution API as a development aid as it is intended for use in dev environments. All references should be removed prior to an actual prod release as there is no need to compile the code into your release swf.

Below I have provided links to the Execution API resources as well as documentation which contains comprehensive use-case examples.

Execution API
IExecutable
Execution

November 3, 2007 Software Engineering

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AS3 StringTokenizer

One useful utility in the java.util package is the StringTokenizer class. I was looking for an ActionScript implementation the other day but was unable to locate one. So after determining the level of effort to write a StringTokenizer in ActionScript was minimal, I decided to roll my own.

The ActionScript StringTokenizer is a convenience class which provides a simple mechanism from which Strings can be extracted into individual tokens based on a specific delimiter.

StringTokenizer provides an IIterator implementation as well as an IEnumeration implementation, thus allowing a StringTokenizer to be implemented as an IIterator or IEnumeration. The interfaces are also provided with the StringTokenizer API.

Ideally a StringTokenizer is to be utilized to tokenize a String into specific tokens and is to be considered read-only. To use StringTokenizer is very simple. The constructor accepts two arguments, both of which are required. The first argument is the source String from which tokens are to be extracted. The second argument is the delimiter from which the tokens are to be based on, as in the following:

var st:StringTokenizer = new StringTokenizer("R.I.A",".");

In addition to the constructor I have provided two static factory methods for creating both the IIterator implementation and IEnumeration implementation. The factory methods require the same arguments as the constructor and are provided as an alternative to the constructor.

var it:IIterator;

it = StringTokenizer.createIterator("R.I.A",".");

// or

var enum:IEnumeration;

enum = StringTokenizer.createEnumeration("R.I.A",".");

All implementations provide operations for determining if elements (tokens) remain as well as operations for retrieving the next element.

A typical StringTokenizer implementations is as follows:

var st:StringTokenizer = new StringTokenizer("R.I.A",".");

while ( st.hasMoreTokens() )

{

trace (st.nextToken() );

}

// outputs

// R

// I

// A

An IIterator implementation would be as follows:

var it:IIterator;

it = StringTokenizer.createIterator("R.I.A",".");

while ( it.hasNext() )

{

trace (it.next() );

}

// outputs

// R

// I

// A

An IEnumeration implementation would be as follows

var enum:IEnumeration;

enum = StringTokenizer.createEnumeration("R.I.A",".");

while ( enum.hasMoreElements() )

{

trace (enum.nextElement() );

}

// outputs

// R

// I

// A

In each use-case the StringTokenizer instance will return the same result as the underlying StringTokenizer implementation (e.g. invoking IIterator.next() results in a call to StringTokenizer.nextToken(), etc).

Source:
StringTokenizer
IEnumeration
IIterator

November 1, 2007 Object Oriented Design

10 Comments

Configurable ContextMenu API update / example

I have received numerous requests for an example which demonstrates how to implement the ConfigurableContextMenu API which I had developed back in February of this year.

In the time since the original post I have re-factored many of the core features, however the goal of the ConfigurableContextMenu API remains the same.

The following is a brief recap from the original post.

The ContextMenu classes in ActionScript 3: ContextMenu, ContextMenuItem, ContextMenuBuiltInItems provide a good base for working with context menus in Flex 2, however they do not provide an intuitive API for developing and working with custom context menus, especially at runtime, so in this regard these classes fall short to some degree.

In order to provide a solution which addresses the issues mentioned above I have developed a ConfigurableContextMenu API which allows developers to dynamically create custom context menus by which items can be added, removed, enabled, disabled, shown, hidden and cloned dynamically at runtime. This API also addresses certain Flash Player restrictions which fail silently in the ContextMenuItem class such as caption collisions and reserved captions restrictions which are simply ignored by Flash Player, leaving the developer clueless (until reading the documentation) as to why the items have not been created.

Below I have provided links to ConfigurableContextMenu resources which include complete documentation, UML class diagrams and basic example Flex application.

example
asdoc
uml diagram

The ConfigurableContextMenu API is published under the MIT license.

October 28, 2007 News / Object Oriented Design / Software Engineering

2 Comments

MD5, SHA1 and SHA-256 Encryption Utility

If you work with different types of encrypted data it is often quite useful to have a utility available from which you can utilize to encrypt a String to a specific encryption format.

I find it particularly useful to isolate each available encryption object into a single Helper / Utility class to help facilitate encryption requests; essentially providing a wrapper for all encryption objects.

The Encryption utility is an all static class which is intended to provide a solution for centralizing access to encryption classes. The Encryption utility simply wraps all encryption types available in a Flex Application and provides a single static method for encrypting a String to the specified encryption type.

Additionally, the Encryption utility provides constants which represent each supported encryption type; SHA-256, SHA1 and MD5.

Using the Encryption utility is simple and straightforward as one might expect. The following examples demonstrate a typical use-case in which a String; “test”, is encrypted utilizing each defined encryption type:

trace(Encryption.encrypt("test",Encryption.CRYPTO_SHA256));

//df3f619804a92fdb4057192dc43dd748ea778adc52bc498ce80524c014b8

//1119

trace(Encryption.encrypt("test",Encryption.CRYPTO_SHA1));

//a94a8fe5ccb19ba61c4c0873d391e987982fbbd3

trace(Encryption.encrypt("test",Encryption.CRYPTO_MD5));

//098f6bcd4621d373cade4e832627b4f6

So if you need an easy to use, centralized location from which you can conveniently call up to encrypt a String, feel free to utilize the Encryption utility.

The Encryption utility is protected under the MIT license.

October 6, 2007 Software Engineering

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MAX 2007 in Chicago

I arrived in Chicago earlier this afternoon as I will be attending MAX North America from Sunday – Wednesday.

This is my first time visiting the “Windy City” and it is a really nice place; very clean and very quite for such a large city, or maybe that’s just because I am used to NYC?

I am staying at the Hilton Towers and the food and drink at Kitty O’Sheas is worth the trip alone. The hotel also has a very interesting historical background as well.

If you should happen to be attending MAX as well feel free to look me up.

I am planning on writing a post soon after I return regarding what I feel were some of the more significant highlights of MAX 2007.

September 30, 2007 News

1 Comment