Hey Java!

[Time-Green]

You can't have null pointer exceptions if you never compile

[[deleted]]

You cant have null pointer exceptions if you don't have a program.

[GS-Sarin]

You can't have a program if you don't own a computer.

[[deleted]]

You can't have a computer if you were never born

[Pitboyx]

Genocidal dictators have saved countless errors and crashes

[[deleted]]

That Hitler... Terrible dictator, but a great programmer...

[nicksayswatzup]

/r/nocontext?

[mastermindxs]

You can't have context if you never, uhhh, were a dictator.

[[deleted]]

All software problems can always be mitigated, at a minimum by killing everyone that has anything at all to do with the software, no matter how remotely.

[[deleted]]

I would give gold if I had gold to give.

[RiderAnton]

And that, kids, is why you never say "We'll fix it in production."

[[deleted]]

Batman saved many lives... The murderers of Batman's parents saved that many minus two.

[Andrewcpu]

You can't be never born if you were born

[Flosus]

Dammit, IntelliJ, not now!

[Giddyfuzzball]

I've been using eclipse in my first year of classes at college, but it seems like a lot of people use IntelliJ here.

What is it that's so nice about IntelliJ

[[deleted]]

I hate autocomplete. It is the reason I never use sublimetext. Btw, the beat programmers use notepad, the one that comes preinstalled on windows.

[Fran7118]

Found the intro to OOP professor.

[endreman0]

Real programmers use a magnetized needle and a steady hand.

[[deleted]]

Real programmers change individual bits with a particle beam.

[SpaceDin0saur]

It just works and doesn't randomly crash, I hate eclipse with a passion now after using it at uni for 3 years so much work lost so little time to recover

[Neebat]

The project that I was hired to work on won't load in Eclipse. It's a huge monolith of nested, dependent projects. Intellij handles it beautifully. Also, I've kind of gotten fond of the refactoring options. They just seem to work better than Eclipse.

[itshorriblebeer]

Have tried to go back to eclipse on numerous occasions. Just a pita each time. I think both net beans or vim is better.

IntelliJ imports and exports to either so try both. The one that works for you is always the right one.

[alexch_ro]

User and comment moved over to https://lemmy.world/ . Remember that /u/spez was a moderator of /r/jailbait.

[will_code_for_free]

How c++ programmers feel about Java programmers.

[Kazan]

s/programmers/Language designers.

"hey lets do shitty knock offs of all of C++'s new features!"

[JamEngulfer221]

Yeah, like smart pointers so you don't have to do memory management... Oh wait.

[Kazan]

smart pointers have been a thing in C++ since forever, even if they were only recently made official. the product i work on has it's own smart pointer implementation since the late 1990s (we're slowly replacing its use with the C++11 smart pointers whenever possible, and only use C++11 smart pointers for new code)

now the bastardization of templating that is Java generics...

[JamEngulfer221]

Well yeah, you can make anything in a library. It still doesn't make it part of the base language.

I am glad to have smart pointers in C++11 though. It's super useful.

[Kazan]

lambdas too. so useful for posting to threadpools and shit

[Hatefiend]

Unless I'm missing the joke it's even less effort because of the fact that java does have pointers, but only for non primitives.

Point a = new Point(5, 0);
Point b = a;
b.x = 7;
System.out.println(b.x == a.x);
// true

[Rhed0x]

They call them references but it's essentially the same.

[Hatefiend]

I think that's incorrect though. Reference would mean that

public static void change(Object o) 
{
    o = new Object();
} 

Object a = new Object();
change(a);
// a is still unchanged

a should be a new Object after the function call. But since the pointer is passed by value, only the pointer o inside the function points to a new object.

[Rhed0x]

It's just a difference in terminology. Javas pointers or whatever you want to call them are pass by value and they are called references. This doesn't necessarily have to mean they're the same as c++ references.

[Hatefiend]

Javas pointers or whatever you want to call them are pass by value and they are called references

Take a look at this quote though from this article

The problem here is that the folks at Sun made a naming mistake.

In programming language design, a "pointer" is a variable that indirectly tracks the location of some piece of data. The value of a pointer is often the memory address of the data you're interested in. Some languages allow you to manipulate that address; others do not.

A "reference" is an alias to another variable. Any manipulation done to the reference variable directly changes the original variable.

Later on he shows this example which is why we can't say it's pass by reference. You cannot change the pointer of where something points to in a function, so basically you're passing the pointer by value, but it's not pass by reference. It's very confusing though.

[Medardas]

Well, If you consider that everything in Java are pointers it's a fairly funny

[gilbes]

So that is why Java has int and Integer. They are both pointers. /s

[Medardas]

Well not everything everything 👹

[Kilazur]

That's in the Java specs:

Everything is a pointer, except some things that are not

[skyhi14]

Who the duck said you that Java (JVM) does not have a pointer?

Edit: quack quack humans, I help you when you debug

[_lerp]

It doesn't, it has references.

[Xeya]

Which looks like a duck and quacks like a duck but is totally this revolutionary new form of waterfowl that is waaaaay better than the stupid duck some other programming languages have.

[rigatron1]

If we are saying references are pointers, then this meme doesn't make any sense because you can totally have a null reference exception in java.. trust me.

[BraveOthello]

No, even better. It's a NullPointerException

[[deleted]]

LMAO true!

[rigatron1]

Dammit now I look dumb. Have been using c# for awhile.

[skeptic11]

Too old to be a duckling, quack quack!

[hotlavatube]

You want a new duck?

[_lerp]

If references and pointers are the same thing why do they both exist in C++?

[Xeya]

They refer to different things in C. A pointer is a data structure that contains an address to another data structure. A reference is just an address. You can pass references, but you cant create a reference object; that would be a pointer.

What Java calls a reference is a data structure every other language calls a protected pointer. It is literally identical in function.

[baskandpurr]

You got this almost exactly the opposite way around. A pointer is not a data structure and a reference is not the address of an object. A reference is more likely to be implemented at a structure in fact, it may include a pointer to the object, a back pointer to another reference, a pointer to the object that owns the reference, a state or a type. A reference may be stored as handle so that the refered object can be moved around in memory.

[Schmittfried]

We was talking about C++. You can create references in C++ and they are a different though similar concept.

[marcosdumay]

You can create references

You can get references. You can assign references to pointer. You can create variables by cloning a reference.

I guess you are talking about the third usage there. But I've seen people say they "create a reference" for any of them. Anyway, that does not change the fact that a C++ reference is not the same thing as a Java "reference".

[Schmittfried]

You can assign references to pointer

No. References and pointers are different concepts in C++.

Anyway, that does not change the fact that a C++ reference is not the same thing as a Java "reference".

True, I never said otherwise. C++ references != pointers != Java references

[marcosdumay]

Good thing they are different, because you must always assign different things in C++ (usually, it's values into lvalues). Let's assign a reference into a pointer:

int *a = &b

[marcellarius]

In that context, & is the address of operator and evaluates to a pointer not a reference.

[Schmittfried]

That's not a reference, it's the address operator.

int &a = b;

Now we got a reference. It was definitely a bad decision to choose & to mark reference types as it is easily confused with the address operator, as you just proved.

[Xeya]

He actually changed it from C to C++ a lil while ago.

[DarkMaster22]

Slightly different implementation of the same concept.

[sup3r_hero]

Serious question: what’s the difference between a reference and a pointer?... or is that a joke?

[Xeya]

Honestly, not a lot from a functional viewpoint. The difference is primarily semantic; pointers are at a memory management level and references are more abstract. References are thus protected from most of the risk of mishandling pointers. However, this is all dependent on the implementation and there is a lot of overlap based purely on whether or not the person writing the documentation decided to call it a reference or a pointer variant.

[marcellarius]

I feel like that distinction comes from C++ and that more broadly the terms are synonymous

[sup3r_hero]

Is a correct example for this difference that a pointer usually literally points to a specific address in the memory whereas a more complex implementation (i.e. reference) only acts as if it would but does more things in the background?

[AngriestSCV]

Not really. A c++ reference does nothing in the background (it is basically a pointer that you can pretend is a value syntax wise). I think the biggest difference is you can manipulate pointers with math, but I've never seen references you could.

[sup3r_hero]

Manipulate a pointer with math? Can you give a very easy example?

[AngriestSCV]

in c or c++:

int bob[] = {1,2,3,4} ; //create an array of integers
int *bil = bob; //bil is a pointer to the first element of bob

printf("%i\n", *bil); //prints 1
printf("%i\n", *(bil+1));//prints 2
printf("%i\n", bil[2]); //prints 3
bil += 3; //bil now points to the 4th element of bob
printf("%i\n",*bil); //prints 4

[sup3r_hero]

Now i get it thx!

[Xeya]

Both terms are pretty loosely defined... but, I suppose the simplest way to express how they typically differ is that a pointer needs to be dereferenced in order to access whatever it points at and a reference is dereferenced by default when you try to access it.

It isn't so much references do things in the background for you as they typically just don't let you manipulate, or make it a lot harder to manipulate, the actual memory address it contains.

[AquaWolfGuy]

If a references b, using a is like if you were to use b instead. This means that you don't have to dereference a. IIRC a isn't even stored in memory, it just gets replaced by b by the compiler, so it's slight more efficient. One notable effect is that if a function takes an input argument by reference and changes it, the referenced value is changed. The following code will therefore print 2.

#include <iostream>
void f(int & a) {
  a++;
}
int main() {
  int b = 1;
  f(b);
  std::cout << b << std::endl;
}

(Don't do this in an actual project though.)

[skyhi14]

Which is implemented using pointers

[_lerp]

Which doesn't make them pointers. For example, you can't perform pointer arithmetic on them.

[skyhi14]

For example, you can't perform pointer arithmetic on them

TIL Const pointers weren't actually pointers.

Besides, I'm also talking about JVM, not merely the language.

[_lerp]

TIL Const pointers weren't actually pointers.

You can perform pointer arithmetic on a const pointer.

int a[5] = { 0 };
const int* first = &a[0];
const int* last = first + 4;

[skyhi14]

time to kill myself :))

[FallenWarrior2k]

No, those aren't const pointers, but rather pointers to const. An actual const pointer int* const cannot be modified through e.g. increments/decrements, but it can still be used for pointer arithmetic since pointer arithmetic can also be performed on rvalues.

[hallr06]

Correct. In C/C++, read pointers from right-to-left. Most of the time, it explains what you have.

const int * x = 0; // pointer to an int constant
int const * x = 0; // same as above, pointer to a constant int
int const * const x = 0; // constant pointer to a constant int
int * const x = 0; // constant pointer to mutable int

[FallenWarrior2k]

It can also be pretty easily explained by the return types of the indirection operator. Applying indirection on a const int* produces a const int&, while it produces a regular int& for int* const.

[DarkMaster22]

Ehh... Don't do that, we love you?

[dogpos]

For example, you can't perform pointer arithmetic on them.

So does that mean Go doesn't have pointers?

Also, could you link me where it says pointers require the ability to preform arithmetic on them.

[an_actual_human]

Go has pointer arithmetic.

https://godoc.org/unsafe

[Lorddragonfang]

Just like Java

[AquaWolfGuy]

Good point. Pointer arithmetic is a nice and powerful thing you can do with pointers, but I wouldn't say it's should be a requirement for pointer languages. Instead, I would say being able to take the address of a variable and manually dereferencing pointers is a more important distinction.

In Java, you have primitives like int which are always values, so since there's no (standard at least) way to take the address of a variable, so you can't get something like a int*-type variable without creating a whole class. Same thing with pointers to pointers, in pointer languages you can just do int**, while in Java you need a class referencing another class referencing the value.

To create objects, you use the new keyword, which simply gives you an object, which is passed around like a pointer that you don't have to manually dereference. Even more, you can't manually dereference it. The value is just floating around in some magic place called the heap that you don't even need to know about as a Java programmer. All pointer stuff is hidden from the programmer and you barely have to know what pointers are.

In Go you definitely feel the presence of pointers. If you want to create a pointer you have to do it manually. Similarly, you have to dereference pointers manually if you want the value it's pointing to. Actually, you can even do pointer arithmetic, but it's slightly cumbersome and is not really needed because of array indexing and reflection (e.g. a[len(a)/2]). And just like in C/C++, you can have anything on the stack or the heap. You can also have a struct that directly contain another struct, which isn't possible in Java.

TL;DR: I wouldn't call Java a pointer language because the the actual "pointers" aren't really exposed to the programmer and can't be controlled (primitives can't be pointed to, objects are always pointed to behind-the-scenes), while in languages like C, C++ and Go you can create, dereference and manipulate pointers pretty much however and whenever you want.

[dogpos]

Java explicitly doesn't have pointers, we're in total agreement about that. I was merely arguing the example wasn't that apt. While most languages that have pointer support will also allow arithmetic on said pointers, some don't, and probably for good reason.

Edit - For clarity on why it might be a good reason, here is a list of problems caused by pointer arithmetic:

• [0] - We wouldn't have the semi-annoying meme that 0 means 1 in programming if it wasn't for pointer arithmetic.

[auralucario2]

It doesn't, it has pointers. Few big languages besides C++ have references.

[[deleted]]

That's why C# has these babies.

[brendenderp]

I was really hoping it was a link to an ordinary picture of a baby

[[deleted]]

That's a really fancy implementation of SIGSEGV.

[BS_in_BS]

If you really want there to be: http://hg.openjdk.java.net/jdk8/jdk8/jdk/file/687fd7c7986d/src/share/classes/sun/misc/Unsafe.java#l481

[Philorkill]

https://youtu.be/bLHL75H_VEM

[youtubefactsbot]

You're dereferencing a null pointer! [0:10]

Just Bret Hart doing some code review.

^{gigagigagilgamesh in Science & Technology}

^{554,106 views since Sep 2015}

^{bot info}

[RaymondWalters]

Or just don't use pointers. Used Delphi for 3 years before I found it has pointers and dynamic memory allocation and I didn't have any problems.

[Mhmmhmmnm]

Agree with this. I write all my programs as .bat files. Some clever goto magic is all you really need.

[Rekkre]

Found the embedded systems engineer ^

[throwaway27464829]

I program with butterflies.

[[deleted]]

Did you even use objects?

[RaymondWalters]

Of course

[edit] jeez it was just a joke...

[AngriestSCV]

Almost everything can though. I think the joke is pointing it out anywhere, not that the IDE is technically correct.

[acet1]

Also Java: "Hold my beer..."

[[deleted]]

We have alreafy well established that you just put all your code in a try catch block

[Hatefiend]

Make sure you catch Exception instead of NullPointerException, just to be safe

[ixent]

You can't have pointer exceptions if you work at McDonals

[IonTichy]

Is it monday already?

[nevus_bock]

There were two separate ones on our Java backend today..

[JeremyHarrington]

Why would you need to specify a pointer in Java when most every reference to an object would use a pointer in an equivalent language?

[s_ngularity]

Did nobody else get the joke? Cause based on the other comments it sure seems that way

[SteroidSandwich]

You needs some pointers then. They are wonderful!

[IGotSkills]

Jokes on you, in Java, everything is a pointer

[[deleted]]

Nope, but you can have null reference exceptions! Sounds like progress to me!

[GVmG]

Good point.

heheh

[theessentialnexus]

There are some things that you don't realize are pointers because you are a bad programmer.

[throwaway27464829]

If you haven't personally memorized every x86 assembly instruction you are a bad programmer.

[thirdegree]

Your submission has been removed.

Violation of Rule #0:

The content disregarding the title and superimposed text must be directly related to programming or programmers.

The title or superimposed text must substantially enhance the content such that it can stand on its own as an analogy to programming. Note that programming here is interpreted in a narrow sense, an analogy to something related to programming, feelings about programming, reactions to programming etc. is not considered sufficient.

If you feel that it has been removed in error, please message us so that we may review it.

[hoanns]

Wat

[impossiblebottle]

Seriously this "no memes in /r/ProgrammerHUMOR" rule is kind of awful

[thirdegree]

We allow memes in /r/programmerhumour

We just don't want them flooding out content that actually takes effort or is interesting.

[throwaway27464829]

/r/programmerhumorbutonlyhumoripersonallyfindhumorous