- Do people still use Ada -- (it was mostly used in the Defense Department)
- Are all applications written in Ada "Legacy"?
- Does Ada knowledge still sell
Do people still use Ada -- (it was mostly used in the Defense Department)
As far as use, Ada isn't mandated for use in the Department of Defense anymore. Most of the work that I've seen and done has been in Java, C, and C++, but there's also use of the .NET framework and I've even heard of projects running other JVM languages such as Scala, depending on how the system will be used. There's probably a lot of code out there in Ada, so I wouldn't be surprised if there's a lot of code reuse and maintenance happening. Given the nature of defense projects, it's hard to come up with specific numbers as to its use.
There is a list of Ada projects and users, but it looks like the last update was in June 2008. There might be more recent lists out there, but I couldn't quickly find any.
Are all applications written in Ada "Legacy"?
If you're asking if there is new Ada development, I wouldn't be surprised if new systems are being written from the ground up in Ada. I would suspect there would be too many, but there are probably some out there. However, I would suspect that most of the Ada work out there is maintenance or upgrades on existing systems, not new development.
Does Ada knowledge still sell
Knowledge in anything sells, if you can find someone who is looking for that skill set. Even if you aren't using Ada in development, I've found that knowing a particular language or framework has changed my opinion and how I use other languages or frameworks. I would suspect that knowing Ada would give you an insight into other methods to design and construct software in other languages as well.
Ada is still heavily used in defense, mission critical, safety critical, real time, embedded systems.
Therefore: Trains, Railways, Planes, Air traffic Control, Satellites, Medical Systems, Nuclear Power Plants etc
for a recent use of ada see : this
"Was" used in the defense department? Last time I checked, it still is. Ada is still as viable as any language for writing new software from scratch. Where it's at a disadvantage is in the availability of existing software to reuse and adapt, and the availability of programmers to help you. However, it can be linked with C programs or those with similar binary interface.
Ada has probably the most idiomatic use of strong typing and generic programming of any language I know. That experience is highly sellable even if not programming in Ada.
I would venture to say that any language that was ever that popular and was not hardware specific in non-tech industry or government will never die in a single generation.
Companies, and doubly so government has too many regulations and other concerns just to upgrade because something is old. Many systems of that age are internally supported anyway so the out of support argument does not fly with those either.
Thomas' answer is good in this instance Ada will be around until everything based on tech before the mid 90's has been replaced in the military, but in general this sort of question always results in this sort of answer because languages that have had a period of significant critical mass never completely die.