There's everything simple about Java. The semantics of Java are actually pretty simple, at least compared to C++. What's complicated are the monstrosities people build with Java, but those aren't inherent in the language.
Saying that Java is complicated because EE exists is like saying that C is complicated because Linux exists: Complexity can be built atop simplicity. And for some reason, Java is a complexity magnet.
I would say that the complexity of a language and the complexity of programs within that language are inversely correlated. Java is a very simple language, but as a result, the programs written in it must be more complicated to make up for the shortcomings of the language.
As an example, Java's lifetime rules are much simpler than those of C++. At some point after all references are gone, the object will be garbage collected. Simple. But as a result of this simplicity, you don't know when the finalizer will be called. You can't use it, for example, to flush and close a file, because you don't know when file will be closed. Instead, you need to use try/except/finally, and so you can't add this to an existing class, because it would require code modification from all the users of the class.
Up until Java 8 and lambda functions, functions could not be passed as arguments to other functions. Therefore, the developer needed to make an entirely new classes derived from "Callable". Complexity that came from the simplicity of the language.
C++ has a lot of complexity in the language itself. I won't deny that. What I will argue is that the complexity of the language enables simplicity in programs.
Edit: Lambda statements came in Java 8, not Java 7.
No, not really. Complexity is not about the language: It's about how you use it. It's not necessarily Java's featureset that makes it so complex, it's its idioms.
C++'s lifetime rules, on most variables, are this: It's allocated until you say it isn't. Some of the vars might be refcounted or GCed, but with GC you've still got the same problem on your hands as finalizers, and refcounting can't handle cycles. Manual memory management is dramatically more error-prone than finalizers ever were (unless you're using RAII, but that's not entirely idiomatic, and cannot be).
As for functions not being able to be passed as args, that's not simplicity, that's a straight up limitation. What makes a language simple is uniformity, simplicity, and consistency. Java has a good deal more of all of these than C++
Complexity in the language doesn't enable simplicity in programs, though, because now your program has to deal with 6000 different special cases.
In any case, Lisp and Scheme are possibly the simplest languages, and are celebrated for their power, clarity, and the simplicity with which they can express programs.
I'd be interested to hear why you say that RAII cannot be idiomatic. With `std::unique_ptr` and `std::shared_ptr` for handling pointers, `std::vector` for handling data arrays, `std::string` for handling char arrays, I would argue that modern C++ is very heavily RAII. At this point, if I have a class that cannot be declared on the stack, with cleanup handled by RAII, I consider it to be a broken class.
Good point on limitations vs simplicity. I think that there are different forms of complexity. Some complexity is necessary, due to the nature of the underlying problem. Other complexity is incidental, being due to poor implementations. As an example of essential complexity, C++ has different declarations for stack-based variables and heap-based variables, while Java does not. This is because Java does not allow classes to be declared on the heap, and so it does not need an extra form of declaration. On the other hand, C++ definitely has lots of incidental complexity as well, mostly due to its long history. Having four different constructs for loops is incidental complexity.
I agree that the idioms are what make Java programs be complicated, rather than the language itself. What I'm not sure on is how much those idioms are needed to overcome limitations in the language, and how much they are unnecessary parts of the culture.
Oh, absolutely on Lisp. Lisp/Scheme are amazingly simple, and amazingly powerful. The one downside that I've found is that it doesn't correspond to the hardware as much. Much of C++'s complexity stems from trying to provide as many features as possible while still compiling down to reasonably fast code.
The main issue with RAII is that you can only do properly if as you say, the classes were designed to be stack allocated.
Also that no one just placed such class in the the heap, and it was missed, because no one is actually doing code reviews or making use of static analysis.
Another issue with best practices and ownership are binary libraries. There isn't any sort of control one can have over them, so they are the place where RAII and ownership just goes out of the window.
In any case this is much worse in C than C++, because at least C++ does offer some language tools to deal with it, however there is no rescue from developers using C with a C++ compiler.
> Oh, absolutely on Lisp. Lisp/Scheme are amazingly simple, and amazingly powerful. The one downside that I've found is that it doesn't correspond to the hardware as much.
Actually it can also be an upside, as you see with the adoption of FP patterns in mainstream languages, including C++.
One of the themes at CppCon was exactly hardware heterogeneity and possible C++ abstractions to take advantage of it, while keeping the algorithms high level.
I feel that the solution to both classes designed for heap allocation and binary libraries is the same: making a decent wrapper around them that obeys RAII. In many cases, this is just requires using `unique_ptr` with a custom deleter.
(Note that the example there is only for use within a single function. If the safe_wrapper is to be returned from a function, then the copy/move operators should be defined as needed.)
Certainly, when passing ownership back to the binary library, you are relying on it to correctly handle ownership. But so long as the ownership is in one's own code, you can easily add the type safety.
Regarding a stack-based class being accidentally placed on the heap, you can't prevent all errors, you can only make it less likely. I'd argue that it is easier to accidentally forget to call a cleanup function than it is to accidentally place something on the heap. With C++11 and up, any calls to "new" should be regarded with deep suspicion.
True on the FP patterns moving in, and I love them. `std::function` is a joy to work with, especially as compared to either C-style function pointers or inheritance from a "callable" type.
> The one downside that I've found is that it doesn't correspond to the hardware as much.
The hardware keeps changing. What Lisp provides is a way to access low-level details when necessary, but with a default mode of operation that is managed (developer-friendly): GC, safety checks, arbitrary precision integers, etc. Like for all languages, a compiler can be told to try more optimizations if you want, and if you are ready to spend a little more work on it. In some implementations, you can extend the primitives known the compiler to emit better assembly code (e.g. https://www.pvk.ca/Blog/2014/08/16/how-to-define-new-intrins...).
Well then, that's your problem: C++ is trying to be both low-level and high level at the same time. This isn't a good idea, IMHO.
What I mean is that while some amount of RAII is a common idiom in C++, It's rare for a program to use RAII fully, as many C++ idioms conflict with it. Mind, I'm not an expert, so I might be wrong, but that was my understanding. AFAICT, if RAII was used all the time, idomatic C++ would look a lot more like Rust.
> Well then, that's your problem: C++ is trying to be both low-level and high level at the same time. This isn't a good idea, IMHO.
It is a very good idea and C++ isn't alone there.
Professional Basic dialects, Turbo Pascal, Delphi, Modula-2, Modula-2+, Modula-3, Ada, D, Rust, Mesa/Cedar all share this idea that you can program at both levels, depending on the needs of the use case.
C++ has less distinction though, and it's so huge that even Bjarne can't keep the whole language in his head. The net result is that many people use the low-level parts of the language for high-level work and vice-versa.
The same applies to the languages I listed, given the amount of years they have.
C++ main issue has always been C's compatibility and the C subculture.
The copy-paste compatibility was necessary to bring C developers over the fence to C++, with minimal changes to their tooling.
So C++ inherited all the flaws and UB from C.
Then many of those kept using C++ as plain C with Classes, which influences many of the design decisions regarding language semantics, specially given backwards compatibility as no one wants to repeat Python's error.
Having said this, although I enjoy playing with template metaprogramming, I hope never have to deal with SFINAE, declpspec and function return arrow syntax in production.
...But that's not often how those languages are used.
And most of those "flaws" aren't flaws in C: They were deliberate design decisons. Arguably bad ones, yes, but they were made a reason. By C++, most of those decisions didn't have any reasons, or were actively against C++'s goals, if not C.
I know you hate C, but blaming C for C++'s problems is like blaming dogs for the monstrous dog demon that someone made with gene editing. C compatability was a bad idea, but you can't blame C for that. Also, it's overly baroque.
But yeah, I think we can all agree that complex TMP is kinda sucky.
It's not Lisp, but OTOH, C++ doesn't need puzzles: Template Metaprogramming, as well as many other parts of the language, are already one. And god help you if multiple programmers on a project use different subsets of the language...
There's everything simple about Java. The semantics of Java are actually pretty simple, at least compared to C++. What's complicated are the monstrosities people build with Java, but those aren't inherent in the language.
Saying that Java is complicated because EE exists is like saying that C is complicated because Linux exists: Complexity can be built atop simplicity. And for some reason, Java is a complexity magnet.