flex to java trying to get started on the plan

Question

I have as suggested recently on this forum been "playing" with arcgis server. For reasons perhaps not obvious to "real" programmers I have built a fairly extensive series of web mapping applications (not real applications) based on flex sample viewer.
It has been very difficult for me to understand the ins and outs of flex but am beginning to get a grip on it.
I stated these are not real applications meaning - when I get an "application working with all the widgets and layers, etc working.
I simply copy that folder structure and rename it to a new application name.
I then edit config.xml (notepad) and default.htm to reflect the new application name.
I don't own any programming software i.e. msvs, flashbuilder, etc.

Because of the power and marketing of apple, I am now in the delimna of whether to find an x-code programmer to help with the esri IOS application, or switch to Java for all applications, and websites.
One problem I have is even understanding the java terminology. Java, javascript, etc. My question is.

Is there an easy to understand resource for Java.
I'm certain there is nothing to convert my flex applications to java.
But has any had experience with what I am going through? Any direction or comment is appreciated.

Answer 1

Here's the short answer to some of your questions:

Java is a programming language similar to C# in both syntax and execution. It compiles to something called bytecode which can then be run on multiple platforms (Unix, Windows, etc.) via a "virtual machine."

Javascript is not at all related to Java. There is no bytecode run on a "virtual machine"; the code is interpreted line by line.

So, what I am assuming you want to do is take the applications you currently have running under Flex and convert them to Javascript so that they can be run in a browser on multiple platforms, i.e. iOS, Android, Windows, OS X, etc.

If that's the case, you'll most likely need to rewrite the applications in Javascript using ESRI's Javascript API. There's no automatic conversion from Flex to Javascript that I'm aware of, so you'd have to start from the beginning when creating the first application. If written correctly, that first application can be used as a template to rewrite the rest of the applications (similar to the way you did with the Flex applications).

Comment if I missed something or if you need a deeper explanation.

Answer 2

Some tips to get you started:

I would first read some tutorials on JavaScript just so you know the basics. If you want some in depth knowledge of JavaScript I'd suggest you to pick up a copy of JavaScript : The Definitive Guide or JavaScript The Good Parts. Although that second book is more for programmers making the move to JavaScript. Then I would take a look at the Basic Viewer template that ESRI published on ArcGIS.com http://blogs.esri.com/Dev/blogs/arcgisserver/archive/2011/10/11/ArcGIS-API-for-JavaScript-2D00-Basic-Viewer-template-now-available.aspx. The code of the template can be found here: http://www.arcgis.com/home/item.html?id=89db99ee00834c85b3f9284d9e81c964. The javascript api docs also have a lot of samples. Note that if you want your site to look good on mobile devices you'll have to ensure that your design is usable on small screen sizes