It's almost impossible to give a single and definite answer as not only usage of programming varies greatly over markets as well as new markets opening and new programmers are added as well, having been trained with different languages.
Big Business Market
One of the biggest, but least visible markets is big business. An area traditionally held by COBOL - on mainframes only challenged by Assembly, but that was at best a 50:20 ratio with the remaining 30% being held by specialized languages - mostly in the mid range applications (RPG etc.).
In addition, this market is defined by mostly maintaining and enhancing existing landscapes to adapt to changing regulatory requirements, adding new business types and so on. That means it's 95%+ improving existing code bases. There is not much room for new languages as existing code, interfaces and tools are where the value is. This of course goes for new applications within a company. It's much less work to write a new COBOL program, despite all the typing and weird constructs with the whole power of an existing and cosy framework.
When Pascal came, in the early 80s, mainframe compilers were soon provided, but it didn't make any notable impact. It was seen as a weakly integrated language, requiring too much effort to add all the interfaces and and framework connections that were present for existing languages.
The same is BTW true for C. IBM and others did provide C compilers as well, but it stayed as much an exotic language, good for some trials but simply not fitting the environment.
By the 90s COBOL was really feeling drag, as newer COBOL standards didn't improve as much as hoped for and Assembler becoming very rare. Where porting COBOL to smaller machines was doable, it wasn't great. And Assembler even less (*1).
A market eager for modernisation is what Java entered in the late 1990s. End it did so with force as IBM, as well as major tool suppliers supported Java as a solution capable to work as integrated and well defined as COBOL, but with all the bells and whistles considered state of the art. Plus the killer argument of write once run everywhere, a perfect match when PCs, small servers and networks started to become reasonable options.
Bottom Line, in this segment the transition was almost direct from COBOL to Java.
Small Business Market
This is an interesting and often overlooked field, as here BASIC was the major language throughout the 1970s up to the late 1980s. Today mostly forgotten companies exclusively focusing on BASIC, like Wang and MAI, ruled the small business world in addition to larger ones like DEC or Olivetti. In fact, they almost entirely created the market with machines like
The strong stand of BASIC in these markets is one reason why BASIC became an important language for the first micros.
Being more diverse than the mainframe market and way more shaped by new companies offering new products, the market was also very open to new and sometimes odd languages.
The small business market never really switched to anything, but was replaced by more generic micros, opening many new markets.
And that's where Ada comes along. On one hand Ada was seen as the next big thing and it could have been if the licencing hadn't screwed fast adaption outside a very special market: Government and Military applications.
Here Ada was for many projects the language 'Par Ordre Du Mufti'. It was part of the project requirement. So switching to Ada was mandatory for everyone working in that business, no matter what his prior language was.
This did of course have as well influence on education, as there was a demand for Ada programmers - except, unlike with other languages, there were no cheap tools education could afford, so spread was, as mentioned, extreme limited.
Switching from Ada to Java did not really happen, at least not as a single move. For one, Ada is still widely used in this area, but equally switching to C or Java happened more on project-by-project basis than generally.
Micros did start out with strong BASIC support, as BASIC was common/compatible with all their target audience:
- Small Business (see above)
- Engineering (think HP)
- Newcomers (BASIC is a learner language)
Pascal did get a good stand with upcoming micros, not least due to being (somewhat) portable between systems (*2). UCSD Pascal, especially Apple's version did make a great environment for business applications (*3) especially due to easy use overlays to get around the limited address space of existing 8 bit micros.
This also nicely fitted the fact that Universities started to use Pascal as teaching language. People are lazy. Why switch if there is already one they know?
The PC changed the landscape a lot due to being a platform offering more than 64 Ki RAM and a large potential customer base. Turbo Pascal for the PC became a major platform.
At that point it must be noted that Apple made the Mac a 100% Pascal environment.
Since it was still a 'startup' platform, that is one where developers did start more or less from scratch, other languages like Modula and most notably C did also get some traction. This was further amplified by Microsoft's goal at the time to slowly switch PC users over to Unix (Xenix) (*4).
When Windows was done it was written in a way to support Pascal as well as C, but looking at MS publications, Pascal examples vanished around the time Windows 3.11 became a success. So Windows was a C platform and C being the language for the PC.
So here C took over from Pascal and BASIC.
When Java came, C was already settled. Java didn't really provide many advantages over the existing C framework, so not much reason to switch. The only exceptions are applications within a company framework that switched to Java with their mainframe environment.
As already noted, schools did go for Pascal as main training language throughout the 1980s. But with an increasing usage of Unix, mostly due to cheap multi user systems and workstations, C crept into universities and more and more teachers replaced Pascal with C simply because they were using it anyway. Also, by the early 1990s C was the language for Unix, Windows and the Mac, making it mandatory for many areas.
Java only came up after that and was, due to its strength in business applications (see big business), more prevalent on courses geared toward those application fields.
So in general, here as well, Pascal was mostly already replaced by C before Java got a hold.
Please note, all of this is just a rough overview. For every one following the above development path, there's another one that had a different experience.
*1 - there were many tools and runtime systems to port mainframe Assembly to mid range/mini computers. Still, it needed much more work than with COBOL, as Assembler applications usually were much more fine tuned.
*2 - Heck, Even I used it for some time around 1983/1984 to develop small tools for IBM customers using Turbo Pascal on my Apple II running CP/M
*3 - But not just business - Wizardry, one of the most spectacular games or the time was fully developed using the Pascal system and its graphics libraries.
*4 - Which BTW did create quite some tension within MS between their Mac developers, betting on Pascal and the PC side :)