Christopher Grant

Connecting Flex to Java with BlazeDS

cgrant — Fri, 20 Nov 2009 19:32:19 +0000

BlazeDS offers a great mechanism to attach your flex application to backend services. In this brief overview we’ll configure flex to call a Java Class and return results. This overview assumes you’ve already setup your IDE with a basic Flex / BlazeDS project.

Main points we’ll cover

Build the Java Class
Expose the Class with Blaze on the server
Configure Flex to find the Blaze service
Build the Flex components to make the call

Build the Java Class

In your IDE switch to the Java view and create a new Java class. We’ll call it HelloFlex. Create a private variable called message. Set an initial value for this variable in the constructor. Finally create a getter method that returns the message string.

package com.grant;

public class HelloFlex {
private String message;
public HelloFlex(){
message=”HI Flex. this is Java. How are you?”;
}
public String getMessage(){
return message;
}
}

Expose the class with BlazeDS on the server

Under your web-inf directory you’ll fine a subdirectory called flex. Within there you’ll see the main config files blaze uses to set up the services. services-config.xml is the main file and has statements to include the others. For this example we’re creating a simple remoting service, so go ahead and open up the remoting-config.xml. Here’s where we’ll set up the configuration for our reomting service.

Blaze calls exposed services destinations. In this remoting-config.xml we’ll set up a destination that points to our HelloFlex class.

Under the default-channels create a new destination as follows.

class=”flex.messaging.services.RemotingService”>

com.grant.HelloFlex

Configure Flex to find the BlazeDS Service

Depending how you set up your workspace that set may already be done for you. In order for flex to know what channels and destinations are available, our application needs to know where these config files are. In Java, these files are in the class path and are included in the build process. In Flex we need to explicitly tell the compiler where these files are.

Right click on the project and choose properties. Under flex compiler you’ll see a textbox for additional compiler arguments. To configure the file location you’ll need an argument here called services which points to the location of your xml files.

You have two options now.

1) If the folder is part of your flex build path you can make a relative reference to the file using the –services= format as follows. Notice the web-inf directory is not included in the definition. In this the folder containing the flex subfolder is on my build path.

2) If the folder is NOT on your build path you can point to the file location. This is the default method that FlashBuilder implements. We’ll use it for this example, however I suggest you move to a relative location style as soon as you can.

For an explicit file system location the flex option is slightly different. Here we use the –services “” format. On my drive the option reads –services “C:\FlashBuilder\dev\MyProject\WebContent\WEB-INF\flex\services-config.xml”

Build the Flex components to make the call

Now we can get back to our flex components and make the actual call. First flip back over to your Flex Perspective and open your main mxml file.

First we’ll define the service:

The id is the name you’ll reference this service elswhere in your flex app. The destination of helloflex needs to match the destination name you entered in your remoting-config.xml

Next we’ll move to some visual components. First lets add a panel to hold our controls.

And add a text box to display some results

Now we’ll add a button on the page to use the service

This is a direct use of the RemoteObject myService. This is not a best practice. Typically you would have a function managing your calls and the button would utilize that function. For simplicity sake I’ve included the direct call for this demonstration. In this example you’ll notice we use the getOperation function and pass in the java method name we want to call.

If you were to run this now you would see no results. We have yet to define what happens when the service gets called. Lets do that now.

Create a script block to hold our action script and add a simple method that puts the response of our service in our textbox.

import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
private function resultHandler(evt:ResultEvent):void
{
result_text.text = evt.message.body.toString();
}
]]>

To use this function we’ll go back to the service and add a handler to manage all responses.

id=”myService”
destination=”helloflex”
result=”resultHandler(event)” />

Your completed code should look like this

http://ns.adobe.com/mxml/2009″
xmlns:s=”library://ns.adobe.com/flex/spark”
xmlns:mx=”library://ns.adobe.com/flex/halo” minWidth=”1024″ minHeight=”768″>

id=”myService”
destination=”helloflex”
result=”resultHandler(event)” />

import mx.rpc.events.ResultEvent;
import mx.rpc.events.FaultEvent;
private function resultHandler(evt:ResultEvent):void
{
result_text.text = evt.message.body.toString();
}
]]>

That’s it! Run the application and pat yourself on the back. Congratulations! Your first end to end Flex-Java app.

Setting up Flex BlazeDS in FlashBuilder

cgrant — Thu, 19 Nov 2009 18:13:33 +0000

One of the most compelling aspects of Flex is its ability to integrate with a wide variety of data sources. Many of the introductory tutorials online teach how to connect to http services to pull data. The result is typically an XML response. Flex makes it easy to manage XML but there are better ways. using XML requires an object on the server to be serialized to a text format which adds processing time. The response is also larger due to the variety of XML tags that need to be added in order to properly represent the object’s structure. Yes I hear you in the back telling me that JSON is a lighter weight response that doesn’t require all the tags. Regardless the response still needs to be parse out in the client. Finally the contract between client and server is not well defined with straight XML or JSON. Web services do provide a strict contract for the interface that the client can rely on but the objects are still serialized with extraneous tags used to define the structure.

BlazeDS utilizes AMF to provide direct links between client and server objects. AMF provides access to objects through a binary protocol and eliminates the need to add additional tags that identify the object structure. It also reduces the work in flex to get the data back into a usable flex object.

Lets start working through an example by getting our workspace setup.

Initial Setup

Flex and Java both need to know about BlazeDS and where to look for the libraries and configuration files. FlashBuilder lends a hand with this by automating some of the process.

First things first, you’ll need to have FlashBuilder installed. The beta version can be downloaded at http://labs.adobe.com/technologies/flashbuilder4/. Also check to make sure you have the WTP extensions installed in eclipse so you can automate creating the web application structure.

Finally for this IDE example we’re going to download the BlazeDS war from adobe at: http://opensource.adobe.com/wiki/display/blazeds/Release+Builds Just download the binary version, we don’t need the full turnkey for this. Once you have it downloaded, extract it to your drive, you should see the blazeds.war when you’re done.

In FlashBuilder create a new Flash project. Select J2EE Application server type. Select Remote object access with BlazeDS and the type. Select create combined Java/Flex using WTP. Click next.

On the next page, for the BlazeDS WAR file, point to the location where you extracted the files from Adobe. The system will pull all the jar files and configs from this war and add them to your project. Click finish.

You’ll notice that FlashBuilder loaded all the Jars and Config files as well as setting up the web.xml.

The web.xml tells java where to find the config files that BlazeDS needs. Remembering that Flex and Java are compiled separately and both need to know where configuration files are, lets find out where the IDE tells Flex about the config files.

Looking under the project properties under flex compiler you’ll see a compiler option is added for services.

NOTE: Without this compiler option Flex would not be able to find the BlazeDS services. When setting up blazeDS manually this flag will needed to be added by hand.

Java vs Flex: In Java the config files are loaded at run time. To change a value in the property file you simply need to restart the server to make it take effect. In Flex however this is a compile time include which means any changes to the files will need to be rebuilt into the application. Just a little note that may save you some headaches later.

That’s is for the setup.

Next time we’ll look at the code needed to use BlazeDS. Stay tuned.

Velocity: Tracking productivity instead of time

cgrant — Thu, 19 Nov 2009 16:05:07 +0000

One of the most interesting parts of Agile project management is watching the velocity of a team increase over time. As a team works together their productivity tends to increase. Agile represents the amount of work a team produces in a metric called velocity. Frequently teams new to agile will size the work in a time based unit such as hours or days. This is a common carry over from traditional project management. While Agile does manage time and resources, the time is fixed not variable. In Agile an iteration or sprint is a fixed length of time typically between two or four weeks. A chart showing time spent working in an iteration isn’t that valuable. A better process is to view the amount of work a team can produce in a specific amount of time. This is called velocity.

One challenge managers have with velocity is attempting to plan work for a new team on a new project since the velocity of the team is not known. Typically the first couple iterations, a new team is still forming and learning how to work together. Over time the estimates and velocity will stabilize. Looking at the velocity of a team as measured in points rather that hours provides a better indication on the performance of the group. Once the velocity begins to stabilize a team can accurately plan the work for a particular iteration.

Lets look at an example. A small team is pulled together to work on a new project. They sit down and estimated 30 stories varying between 2 and 10 points of effort each. The team believes they can take on 30 points in the first iteration (two weeks). At the end of that iteration the team only completed 10 points. When planning the next iteration the team learns from the previous one and only plans to complete 15 points. Iteration 2 hits the mark, the team does complete 15 points. For Iteration 3 the team plans for 15 points again. This time however they are able to complete 17 points, they’re getting better. Iteration 4 they plan for 18 points but produce 22. Iteration 5 they plan for 20 but only produce 18. Feeling they’ve identified the standard velocity at 20 points, the team continues through the project allocating 20 points per iteration. With this in mind the team can look at the work produced and determine how productive they are and forecast a valid completion timeline. This forecast is the projected project burn-up. The burn up chart shows the actual accumulated work completed against the projected values across multiple iterations. The burn-up chart can also chart scope increases and decreases A burn-down chart on the other hand deals with a fixed amount of work and shows the amount of that work completed in a single iteration. Both of these commonly used planning and status charts can’t be produced without understanding what the velocity of the team is.

It’s tempting to use time as a unit of measurement in agile. Try to break away from the traditional views and track productivity instead. The results will be a more confident team and more accurate planning a reporting. In the end your customers will thank you for delivering what you said when you said, and for providing valuable statuses along the way.

Resources:

http://agilesoftwaredevelopment.com/blog/jackmilunsky/significance-story-points

http://www.versionone.com/Resources/Velocity.asp

http://grantjoung.blogspot.com/2009/07/efficiency-must-have-agile-metric-as.html

http://agilesoftwaredevelopment.com/blog/pbielicki/predicting-team-velocity-yesterday-weather-method

Pragmatic Flex

cgrant — Mon, 09 Nov 2009 02:16:24 +0000

Stay tuned for a new series a new website. http://PragmaticFlex.com is coming soon.

Layers of Architecture

cgrant — Fri, 16 Oct 2009 21:37:42 +0000

There are tons of architects out there today. It seems when you’ve spent enough time as a developer, you end up becoming an architect. Architecture is not just the next step in a developers career. There are whole new disciplines and methodologies applicable to architecture. That said here are the common levels of architecture.

Enterprise Architecture (planner)

Enterprise architecture is a high level field that concentrates on how the various domains or subject areas interact. This layer spends even more time focusing on how technology will be utilized in the future, and governing how it is used today. Enterprise architects work to create technology roadmaps and work with the business to plan for the implementation. Enterprise architects create technology projects. It is at this layer where frameworks like TOGAF and taxonomies like Zachman come into play. This layer view the enterprise as a holistic entity.

Solution Architecture (designer)

A solution is an answer to a question. The question in this case is typically an IT project. The solution architect’s primary objective is to design a solution that meets the projects requirements and also falls in line with the domain and enterprise architecture guidelines. The solution architect is responsible for coordinating with multiple domain architects to design the most appropriate solution. A solution architect may interact with domain architects in infrastructure, web services, data management, and so on. During the course of the project a solution architect will typically create many work products either for communicating the solution to a governance board, to explain the implantation to a developer and various other uses. These work products are eventually owned by the domain architect as codified knowledge of the system after the project implementation.

Domain Architecture (owner)

A domain is an area of focus. Domain architects are primarily focused on maintain a specific area of technology or a specific application. These architects are the owners and gatekeepers for a specific area. The work in this area is primarily concerned with the current state of the system. These architects are charged with managing the knowledge for their area. These architects are also responsible for keeping up to date on future projects related to the domain and guiding the designs to meet the overall objectives of the domain. A successful domain architect will know that a future project will require x functionality. When an active project is debating between two possible implementations, the domain architect will be able to guide solution toward the best of the two solutions that meet the future goals.

Application or System Architecture(builder)

The application or system architect is primarily focused on the implementation at hand. This is the most detailed level of architecture. An application architect, for instance, would be concerned with the most appropriate design pattern to use in a certain programming situations. These tend to evolve from the most advance developers and engineers. The primary focus here is to implement the best solution for a specific task. Work products that may be produced during this layer are primarily used to communicate to the developers or implementers. In many co-located environments a lead developer often fills this role and very few work products are actually produced. Instead the team may utilized whiteboards or code stubs to communicate the implementation. For larger more dispersed projects, or for outsourced solutions, the application or system architect has a more demanding role for providing detailed implantation instructions.

Conclusion

The various layers of architecture are not meant to be isolated entities. In most situations one architect will fill multiple roles at various levels. Each layer has a unique focus. Understanding the layers helps clarify responsibilities, activates and deliverables. From a career development standpoint individuals can use the layers as the basis for a personal gap analysis and learning plan.

I look forward to reading your thoughts and comments.

Best of luck in all your endeavors.

Working with Offshore Teams: Tips from the Trenches

cgrant — Thu, 08 Oct 2009 15:44:59 +0000

I’ve had the opportunity to work with a variety of offshore teams on various projects. While very challenging these relationships can indeed be valuable. So how do you make the most of these partnerships? Here are a few observations.

Language

The most challenging piece of an offshore partnership is the language differences. While most business people around the world speak English, it will typically be a British version and/or be accompanied by a heavy accent. This all becomes more difficult when trying to communicate on a conference call with a choppy reception and the other end sounding like they’re in an auditorium.

How to deal with it. There is no good answer here. Two approaches seem to help, first have someone onsite to act as a translator. This is typically someone from the same vendor, who has been assigned onsite. Ultimately though you need to become accustom to the language, this only comes with time. Surround yourself with people who speak the language. Don’t be afraid to say you don’t understand. When on the phone be sure you’re able to concentrate on the call with little background noise or distractions. Overtime the accents will become more understandable and the language gaps will be clearer.

Communication

Surprisingly talking does not equal communication. When dealing with any remote team, clear communication is critical. To frequently conference calls are stressful and where in a normal situation you would ask for more information, on a call you may feel it’s too difficult and you’ll just send an email. Conference calls are critical for a project. Don’t let them go to waste. Ask questions be sure that your question was understood correctly. I’ve found it’s difficult to get participation from an offshore team on a conference call. Typically one individual will do all the talking. Work to get more than yes and no answers and more participation from the whole team. Also in these calls try to encourage conversation outside the simple status updates, you might find out important information.

Beyond the conference call its important to follow up with a clear recap of what occurred on the call. This helps make sure everyone on the call is on the same page and all action items are assigned. With any remote team, following the activates between discussions is difficult. Use email frequently. Insist on a formal agenda and meeting minutes. Clarify action items and blocking issues. If a blocking issue does arise take care of it immediately.

Culture

There are significant culture differences that come into play when dealing with international vendors. These culture differences are stem from national/ethnic traits, to corporate/vendor culture. There are traits that surface simply due to the continued relocation of team members.

My experience has been that Indians don’t tend to question authority. I’m not saying challenge authority, but rather look for clarification and understanding. What seems to happen is that individuals will take a message from a higher-up or client that may not be clear, and instead of working with the source to understand it, they will go to their peers to help understand the message. While this may work in some situations, often times it takes much longer to get the right information. When this works the best is when there are a series of mentors available to the offshore team. A series of experienced individuals various team members can turn to. To help this process, try to keep one vendor and one team as long as possible. Inevitably the vendor will swap out resources on you but hopefully you can hang on to a few key resources that can fill this mentor role. When working one-on-one with an offshore resource be sure you have been understood clearly, ask them to repeat what needs to be done, not simply do you understand.

Working culture. These guys work hard, really really hard. They work nights and weekends, often they work far from their families. Even in India they will travel to different cities to work in central location for a client. It is so important to realize these guys a working really hard for you. Take time to make that personal connection with them (if they let you). Get to know your offshore team by name. Express your gratitude to them individually for their effort. A note about working habits, since these folks don’t technically work for you, they may not tell you when they’re going on vacation. Ask regularly when upcoming holidays are and what vacations are planned so you don’t end up with a skeleton crew right before a huge deployment. If you have on site resources realize when they take vacation it’s typically for a month so they can get back to India.

Conclusion

Offshore and outsource projects can be highly effective if leaders take the time to consider the variety of challenges the show up in these situations. Communication is always a critical component of any business initiative. In an offshore model communication is more important than ever. Leaders are dealing time zone changes, language differences, and cultural differences. All these challenges can be overcome with increased and clear communication.

Consumers are Spoiled Rotten

cgrant — Wed, 07 Oct 2009 14:31:30 +0000

What I want, When I want it, How I want it

That’s how to grow your business these days. Give people what they want when they want it and how they want it. This really isn’t a new thing in business, after all isn’t that the basis of fast food? The difference is this trend is moving to almost every element of life. The culture in business is changing from a world where we all attend meeting at the same place and time to one where decisions are made with people in different locations and contributions coming at different times of the day. Phone calls have been replaced by emails and text messages. This is all old news.

Business need to continue adapting to these changes. The success of iTunes music store is a prime example. Rather than purchasing an album full of music I don’t want just to get a single song I do, I can buy just the one song. Newspapers are feeling the strain as well. The challenge newspapers face is not the transfer to a digital medium, rather its the fact that people only want to see what they’re interested in. Why flip through 3/4 of the newspaper searching for the 1/4 of content I want to read. Look now to the video industry. Yes Tivo ushered in the ability to watch what I want when I want, oh and by the way skipping all those money making ads. Look further though and we see that stores like Blockbuster are suffering because it’s easier to go to my mailbox than a store. Its easier to stream Netflix movies than go to my mailbox. Look at Hulu, where its easier to watch an missed TV episode than try to record a rerun.

How will companies take advantage of selective satisfaction in the future? The magazine industry, led by Time, is looking to roll out a Hulu like online magazine distribution system. Cable companies are offering Video On Demand. Yet how do we deal with the money aspects of all this.

There are a couple of industries that still need to pick up on these new trends. The radio and advertising industries haven’t picked up on all this yet. Why isn’t there a RaDo for an audio version of TiVo. Advertising, too many times I’ve heard or seen and ad that actually peaked my interest but I had to act now to review more details. Why not allow me to have an option to review later. Let me click a button on a web page that adds the info to a folder I can review later, or hit a button on the radio to tag the ad as interesting so I can check it out when I have time.

The world is spoiled. Rather than force customers to work your way, how are you transforming your business to provide what they want, when they want and how they want.

Types of presentations

cgrant — Tue, 06 Oct 2009 15:51:45 +0000

An effective way to prepare a presentation is to begin with a clear understanding of the purpose of the presentation. Generally there are three main types of presentation, each with a different goal. Depending on which type you’re targeting, your content and focus may change.

Discussion Presentation

The primary goal of a discussion presentation is to gather input and feedback from the audience. Discussion presentations are most effective when one or more discussion questions are clearly defined and communicated to the audience. Supporting background information is typically provided to provide context before opening up for discussion. A typical audience for a discussion presentation would include subject matter experts and other core individuals. Multiple discussion presentations may occur in order to include all facets and aspects of a discussion. For example an initial discussion may present a challenge and solicit possible options. A second discussion may present the proposed solution to all impacted parties to solicit feedback from those individuals.

Inform Presentation

Informational presentations are typically geared to larger more general audiences. The focus of an informational presentation is more “matter of fact” in nature, discussing the facts of a situation. Presentations of the Inform type don’t typically ask questions of the audience. Ideally those questions that do surface would look to clarify points within the presentation. Inform presentations can also be thought of as training presentations. The objective is to communicate information clearly from one group to another.

Approval Presentation

Once various alternatives have been considered and evaluated, the Approval presentation provides the opportunity to explain the problem and proposed solution for acceptance by leadership or governing entities before moving forward. Effective approval presentations typically frame the problem, as well as process that led to the solution. With the objective of this presentation type concluding with a yes or no decision, all efforts should be made to answer potential questions well before the actual presentation. This type of presentation should avoid debates about the correct way to accomplish something. Those discussions should occur before this in discussion presentations. The result of those debates and discussion should be summarized in the approval presentation.
Effective approval presentations provide a clear explanation of the problem faced, summary of findings and options reviewed, as well as a brief overview of the steps taken that led to the proposed solution. Most importantly the presentation should clearly communicate what the audience is being asked to approve. At the conclusion of the presentation the audience should have a solid understanding of their task at hand and information required to accomplish the task and approve or deny the proposal.

Conclusion

Regardless of your situation, beginning with a clear understanding of your objective is critical for achieving success, and presentations are no exception. Clearly identifying your presentation type enables you to guide and focus the discussion to meet the real objectives of your presentation. Utilizing the Discuss, Approve, and Inform concepts will help you succeed in your future presentations.

Dropbox Seamlessly Syncs Files – PC, Mac, iPhone

cgrant — Sun, 04 Oct 2009 00:30:17 +0000

Dropbox is a file synchronization service available for multiple platforms. The service offers free accounts that allow up to 2GB of storage space. For those of you needing more, upgrade plans are available. The clients are light weight and run in the background.

One of the nice features of the system is the file monitoring kicks off the sync on every save. The process Is very quick because the system transfers only the file changes rather than the whole file.

This is all great but the feature that won me over is the new iPhone app that allows access to all the files in your sync folder. Photos, word docs, PDFs and more are all available through this app.

Contrasting the app to other tools such as DataViz’ Documents To Go and box.net, Dropbox provides most the the same features better and cheaper. Honestly I found Documents To Go to cumbersome and expensive. The sync mechanism requires the iphone to be on the same wireless network as the host system. Additionally all the documents are downloaded to the iPhone, thus taking up space. Dropbox is internet based allowing you to access your documents regardless of network access method and loading only the document you’re interested in. Box.net does provided some of the same features as Dropbox but lacked the seamless file system integration. When I reviewed box.net the process required you to upload the documents manually to the server to be shared. While there is webdav integration, there was no local copy for off-line use. Dropbox manages the synchronization of files between computers behind the scenes providing local copies for offline use.

I’m impressed with Dropbox’s seamless and cost effective sync solution. Check it our for yourself.

Welcome

cgrant — Fri, 02 Oct 2009 18:24:03 +0000

Christopher Grant is a Technology Leader in Columbus OH with and MBA and over 12 years experience focusing in the Internet and Architecture fields. Christopher is currently employed as a Sr. Technical Architect for Gap Inc Direct. His work with businesses in a wide variety of industries and varying sizes demonstrates his adaptability and versatility. He is classified as INJT on the Myers-Briggs topology. Christopher combines his business background, leadership qualities and comprehensive knowledge of technology to provide organizations with successful long-term strategies and exacting tactical execution.

This blog provides a venue for discussing various topics from business, technology, and whatever else may arise. Please feel free to contact with any questions or comments.

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