Andrew Schwabe's Blog - Java

My new articles on packt publishing

Thu, 11 Mar 2010 19:44:00 -0400

Packt Publishing asked me to write a bit about Railo. It took me forever due to being busy (as always), but here they are! Enjoy and share the love. Introduction to Railo Open-Source CFML Engine:
http://www.packtpub.com/article/introduction-to-railo-open-source Tutorial: Rendering web pages as PDF using Railo
http://www.packtpub.com/article/rendering-web-pages-pdf-using-railo-open-source

CF United 09 Presentation Files - Google App Engine and Flex

Thu, 13 Aug 2009 01:42:00 -0400

Ok folks, here are my preso files for my CF United 2009 talk on Google App Engine and Flex. Is this the final version? Sure. Until I change it. I shall resist doing that... Here is the powerpoint presentation download: 294_Andrew_Schwabe_Google_App_Engine_Flex.ppt Here is the full download (warning, this is big!) Contains all 4 google app engine java projects, all 4 flex projects and the powerpoint file. The download is big because of all the jar files. I will try to have a USB key with me so if you want a super fun time instant copy instead of downloading it, I should be able to do that. Full download (94MB, zipped): CFun09_GAE_Files.zip For those of you web surfers interested -- demo 4 project includes a fix for allowing Flex app using AMF to retrieve Google Account information (using ajax and a custom auto servlet) so your Flex apps can determine if you are logged in, and get your user identifier if you are logged in.

CF United Update: Google App Engine + Flex

Thu, 30 Jul 2009 20:02:00 -0400

My talk at CFUnited has changed a bit... Since the topic was chosen a while back, Google has released a Java developer environment and eclipse plugin for Google App Engine (GAE). Since Java is a whole lot closer to CFML than python is, I've updated all my code and presentation to focus on the Java application architecture, and how to connect it to Flex. I've even got some tidbits on how to get CFML running on Google App Engine ! Be sure to come on out and learn about the exciting new "super scalable" web application system running on Google's free hosting infrastructure.

Flex 2 Boot Camp

Mon, 13 Aug 2007 02:00:00 -0400

I decided to attend a one-day bootcamp for Flex 2 in New York City which was piggy backed onto a RealWorld Java Conference. Our instructors were Yakov Fain and Victor Rasputnis from www.faratasystems.com (they make some cool Flex add-ons you should check out).

It was a day of intensive brain crunching. It seemed to me that it was definitely aimed at Java developers (how many CF developers know what ant is?) more than anything else. A lot of the topics covered were already very familiar to me, including a lot of the Flex code itself -- at least until the second part of the day. What was significant about the second part of the day was the software engineering insight as to how to approach flex apps over the "out of the box" approach Adobe (and formerly Macromedia) used to present.

We covered topics such as compiling re-usable code into SWC files, logging and optimizing data traffic between your DB and Flex using ADF instead of slower verbose web services. These were topics I haven't seen covered anywhere else.

Overall money well spent, though there were some clear holes in the offering as a whole. We jumped into advanced topics pretty quickly; we only covered a few simple UI components; Mac problems. Don't get me started on the Mac problems.... word to those out there: Macs may me great for desktop publishing, but dont expect things to run smoothly when you are trying to develop enterprise class client-server apps on your Mac. nuf sed.

The Good:

- Low cost (around $1000)
- No long hotel stays
- Good material (enterprise application architecture, modularized code, technique)
- Good foundation of when/how to use Flex for an app.
- Excellent coverage of ADF and communication with server side apps
- You walk away with working code on your laptop

The Bad:

- Don't expect all the dev software it to work on your Mac
(I use a PC -- with no problems i might add -- , so im not "talking" about myself here)
The Mac delays caused us to lose about an hour of instruction time -- which for a single day seminar really hurt.... (hey Yakov and Victor -- if you see this, maybe a discount is in order for future bootcamps?)
- Topics jumped from relatively simple to very advanced in the blink of an eye
- Not quite enough coverage of the UI components in Flex
- No coverage of "states" in Flex (pretty essential if you ask me)
- Not enough coverage of http and web service connections (since 90% of flex developers will use this exclusively over ADF/server side components)

Hope this is helpful. Watch my blog for announcements of new exciting flex stuff I am building!

Aptana plugin for Eclipse

Tue, 17 Jul 2007 11:36:00 -0400

Hopefully a lot of you ColdFusion developers are using Eclipse now with the CFEclipse plugin. Many developers dont know about the Aptana plugin however (http://www.aptana.com/). This free plugin gives you all the stuff that you miss from DreamWeaver or Homesite+ -- html and css editing, etc. In addition you get an XML editor, and a fantastic ftp interface, which is sorely needed in Eclipse. Aptana has a very nice ftp synchronization tool set which allows you to effectively develop locally and synchronize to an ftp site.

For those who are curious about how we have our Eclipse configured, here it is:

Eclipse 3.2.x
CF Eclipse 1.3.x
RDS Plugin (from Flex Builder 2)
Aptana plugins
Violet UML plugin

Server side HTTP Post using JSP

Thu, 11 Jan 2007 02:00:00 -0400

Ok, so I use a rapid application development technology (ColdFusion or PHP) most of the time because customers demand such quick turnaround. This time I needed to go back to goold old Java and do some integration.

Our email list management service (Sound-Off 3) manages people's email lists and lets them schedule mailings, etc. I needed to integrate a website build on JRun (using Java Server Pages aka jsp) so that when people register, it relays the info to Sound-Off 3.

In ColdFusion, you can easily do this with a CFHTTP tag. In JSP it is a little more involved. My struggle is your benefit, b/c here is the code that does it in JSP.

This code will do an HTTP POST from the WEB SERVER to the remote site, all behind the scenes on the server. The "parameters" string contains the form values that will be sent to the remove server. Note the leading/trailing &'s and that the form values must be URL encoded.

try
{
    String stuff = null;
    String pagecontent = "";
    String parameters = "&message=hello+world&";
    java.net.URL url = new java.net.URL(http://www.yourhost.com/page.cfm);
    java.net.HttpURLConnection conn = (java.net.HttpURLConnection)url.openConnection();
    conn.setRequestMethod("POST");
    conn.setRequestProperty("Content-Length", "" + Integer.toString(parameters.getBytes().length));
    conn.setRequestProperty("Content-Language", "en-US");
    conn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
    conn.setDoInput(true);
    conn.setDoOutput(true);
    conn.setUseCaches(false);
    conn.setAllowUserInteraction(true);
    java.io.DataOutputStream printout = new java.io.DataOutputStream (conn.getOutputStream ());
    printout.writeBytes (parameters);
    printout.flush ();
    printout.close ();
    java.io.BufferedReader in = new java.io.BufferedReader(new java.io.InputStreamReader(conn.getInputStream()));
    while ((stuff = in.readLine()) != null)
    {
         pagecontent += stuff;
    }
    in.close();

%>success! <%
}
catch (Exception e)
{
%>error!<%
}
%>

And thats it! You can (and should) do further error checking by examinging the contents of "pagecontent" which will have the html code returned from remote website.

Have fun...

Using JFreeChart with ColdFusion

Fri, 22 Jul 2005 02:00:00 -0400

This was originally posted in Christian Cantrell's blog.

Well, your post just helped me figure out a long time nagging problem. I have been working on a CF wrapper for JFreeChart to generate on-the-fly charts, and have been stumped with corrupted output, until I saw your fix about the double getResponse() method calls. With that change, all works great!

For those who don't understand WHY you might need to do this, here is sampe code that creates a bar chart on-the-fly (no caching on the file system) and outputs directly to the browser a JPEG image (or a PNG with incredible quality!):

barDataset = CreateObject("java", "org.jfree.data.category.DefaultCategoryDataset");
Randomize(numberformat(timeformat(now(),"ss")));
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2001", "Q1");
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2001", "Q2");
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2001", "Q3");
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2001", "Q4");
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2002", "Q1");
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2002", "Q2");
rval = int(randrange(1,500));
barDataset.setValue(numberformat(rval), "2002", "Q3");
rval = int(randrange(1,500)); barDataset.setValue(numberformat(rval), "2002", "Q4");

chart = CreateObject("java", "org.jfree.chart.JFreeChart");
chartfactory = CreateObject("java", "org.jfree.chart.ChartFactory");
chartorient = CreateObject("java", "org.jfree.chart.plot.PlotOrientation");
chartutil = CreateObject("java", "org.jfree.chart.ChartUtilities");

chart = chartfactory.createBarChart3D ("Sample Bar Chart", "Category", "Value", barDataset, chartorient.VERTICAL, true, true, true);

response = getPageContext().getResponse().getResponse();
response.setContentType("image/jpeg");

chartutil.writeChartAsJPEG(response.getOutputStream(),
   100, // jpeg quality 0-100
   chart, // chart object
   500, // width
   300); // height

response.flush();
response.close();

If anybody else needs help with the above code, email me.

cheers