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Question ahead:
why does in Java the call coll.contains(null) fail for ImmutableCollections?
I know, that immutable collections cannot contain null-elements, and I do not want to discuss whether that's good or bad.
But when I write a Function, that takes a (general, not explicit immutable) Collection, it fails upon checking for nulls. Why does the implementation not return false (which is actually the 'correct' answer)?
And how can I properly check for nulls in a Collection in general?
Edit:
with some discussions (thanks to the commenters!) I realized, that I mixed up two things: ImmutableCollection from the guava library, and the List returned by java.util.List.of, being some class from ImmutableCollections. However, both classes throw an NPE on .contains(null).
My problem was with the List.of result, but technically the same would happen with guaves implementation. [edit: It does not]
I am distressed by this discussion!
Collections that do this have been a pet peeve of mine since before I wrote the first collections that eventually became Guava. If you find any Guava collection that throws NPE just because you asked it a perfectly innocent question like .contains(null), please file a bug! We hate that crap.
EDIT: I was so distressed that I had to go back to look at my 2007 changelist that first created ImmutableSet and saw literally this:
#Override public boolean contains(#Nullable Object target) {
if (target == null) {
return false;
}
ahhhhh.
why does in Java the call coll.contains(null) fail for ImmutableCollections?
Because the design team (the ones who have created guava) decided that, for their collections, null is unwanted, and therefore any interaction between their collections and a null check, even in this case, should just throw to highlight to the programmer, at the earliest possible opportunity, that there is a mismatch. Even where the established behaviour (as per the existing implementations in the core runtime itself, such as ArrayList and friends, as well as the javadoc), rather explicitly go the other way and say that a non-sequitur check (is this pear part of this list of apples?) strongly suggests that the right move is to just return false and not throw.
In other words, guava messed up. But now that they have done so, going back is potentially backwards compatibility breaking. It really isn't very - you are replacing an exception thrown with a false return value; presumably code could be out there that relies on the NPE (catching it and doing something different from what the code would do had contains(null) returned false instead of throwing) - but that's a rare case, and guava breaks backwards compatibility all the time.
And how can I properly check for nulls in a Collection in general?
By calling .contains(null), just as you are. The fact that guava doesn't do it right doesn't change the answer. You might as well ask 'how do I add elements to a list', and counter the answer of "well, you call list.add(item) to do that" with: Well, I have this implementation of the List interface that plays Rick Astley over the speaker instead of adding to the list, so, I reject your answer.
That's.. how java and interfaces work: You can have implementations of them, and the only guardianship that they do what the interface dictates they must, is that the author understands there is a contract that needs to be followed.
Now, normally a library so badly written they break contract for no good reason*, isn't popular. But guava IS popular. Very popular. That gets at a simple truth: No library is perfect. Guava's API design is generally quite good (in my opinion, vastly superior to e.g. Apache commons libraries), and the team actively spends a lot of time debating proper API design, in the sense that the code that one would write using guava is nice (as defined by: Easy to understand, has few surprises, easy to maintain, easy to test, and probably easy to mutate to deal with changing requirements - the only useful definition for nebulous terms like 'nice' or 'elegant' code - it's code that does those things, anything else is pointless aesthetic drivel). In other words, they are actively trying, and they usually get it right.
Just, not in this case. Work around it: return item != null && coll.contains(item); will get the job done.
There is one major argument in favour of guava's choice: They 'contract break' is an implicit break - one would expect that .contains(null) works, and always returns false, but it's not explicitly stated in the javadoc that one must do this. Contrast to e.g. IdentityHashMap, which uses identity equivalence (a==b) and not value equality (a.equals(b)) in its .containsKey etc implementations, which explicitly goes against the javadoc contract as stated in the j.u.Map interface. IHM has an excellent reason for it, and highlights the discrepancy, plus explains the reason, in the javadoc. Guava isn't nearly as clear about their bizarre null behaviour, but, here's a crucial thing about null in java:
Its meaning is nebulous. Sometimes it means 'empty', which is bad design: You should never write if (x == null || x.isEmpty()) - that implies some API is badly coded. If null is semantically equivalent to some value (such as "" or List.of()), then you should just return "" or List.of(), and not null. However, in such a design, list.contains(null) == false) would make sense.
But sometimes null means not found, irrelevant, not applicable, or unknown (for example, if map.get(k) returns null, that's what it means: Not found. Not 'I found an empty value for you'). This matches with what NULL means in e.g. SQL. In all those cases, .contains(null) should be returning neither true nor false. If I hand you a bag of marbles and ask you if there is a marble in there that is grue, and you have no idea what grue means, you shouldn't answer either yes or no to my query: Either answer is a meaningless guess. You should tell me that the question cannot be answered. Which is best represented in java by throwing, which is precisely what guava does. This also matches with what NULL does in SQL. In SQL, v IN (x) returns one of 3 values, not 2 values: It can resolve to true, false, or null. v IN (NULL) would resolve to NULL and not false. It is answering a question that can't be answered with the NULL value, which is to be read as: Don't know.
In other words, guava made a call on what null implies which evidently does not match with your definitions, as you expect .contains(null) to return false. I think your viewpoint is more idiomatic, but the point is, guava's viewpoint is different but also consistent, and the javadoc merely insinuates, but does not explicitly demand, that .contains(null) returns false.
That's not useful whatsoever in fixing your code, but hopefully it gives you a mental model, and answers your question of "why does it work like this?".
Are there any performance or memory differences between the two snippets below? I tried to profile them using visualvm (is that even the right tool for the job?) but didn't notice a difference, probably due to the code not really doing anything.
Does the compiler optimize both snippets down to the same bytecode? Is one preferable over the other for style reasons?
boolean valid = loadConfig();
if (valid) {
// OK
} else {
// Problem
}
versus
if (loadConfig()) {
// OK
} else {
// Problem
}
The real answer here: it doesn't even matter so much what javap will tell you how the corresponding bytecode looks like!
If that piece of code is executed like "once"; then the difference between those two options would be in the range of nanoseconds (if at all).
If that piece of code is executed like "zillions of times" (often enough to "matter"); then the JIT will kick in. And the JIT will optimize that bytecode into machine code; very much dependent on a lot of information gathered by the JIT at runtime.
Long story short: you are spending time on a detail so subtle that it doesn't matter in practical reality.
What matters in practical reality: the quality of your source code. In that sense: pick that option that "reads" the best; given your context.
Given the comment: I think in the end, this is (almost) a pure style question. Using the first way it might be easier to trace information (assuming the variable isn't boolean, but more complex). In that sense: there is no "inherently" better version. Of course: option 2 comes with one line less; uses one variable less; and typically: when one option is as readable as another; and one of the two is shorter ... then I would prefer the shorter version.
If you are going to use the variable only once then the compiler/optimizer will resolve the explicit declaration.
Another thing is the code quality. There is a very similar rule in sonarqube that describes this case too:
Local Variables should not be declared and then immediately returned or thrown
Declaring a variable only to immediately return or throw it is a bad practice.
Some developers argue that the practice improves code readability, because it enables them to explicitly name what is being returned. However, this variable is an internal implementation detail that is not exposed to the callers of the method. The method name should be sufficient for callers to know exactly what will be returned.
https://jira.sonarsource.com/browse/RSPEC-1488
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Closed 10 years ago.
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When is a Java method name too long?
I know this is probably is a question of personal opinion, but I want to know what's standard practice and what would be frowned upon.
One of my profs in university always seems to make his variable and method names as short as possible (getAmt() instead of getAmount) for instance.
I have no objection to this, but personally, I prefer to have mine a little longer if it adds descriptiveness so the person reading it won't have to check or refer to documentation.
For instance, we made a method that given a list of players, returns the player who scored the most goals. I made the method getPlayerWithMostGoals(), is this wrong? I toiled over choosing a way to make it shorter for awhile, but then I thought "why?". It gets the point across clearly and Eclipse makes it easy to autocomplete it when I type.
I'm just wondering if the short variable names are a piece of the past due to needing everything to be as small as possible to be efficient. Is this still a requirement?
Nothing inherently wrong, it's better to make it descriptive than cryptic. However, it's often code-smell for a method that is trying to do too much or could be refactored
Bad: getActInfPstWeek
OK: getAccountInformationForPastWeek()
Better getAccountInformation(DateRange range)
I prefer to have long variable/method names that describe what's going on. In your case, I think getPlayerWithMostGoals() is appropriate. It bothers me when I see a short variable name like "amt" and I have to transpose that in my head (into "amount").
Something like getAmt() is looks like C++ code style... In java usually are used more descriptive names.
Your professor made a good understandable method. But it's very popular word. It's not a general case. Use your "longWordStyle" style it's more java.
As per standards, longer descriptive names are advised to make it more readable and maintainable on longer term. If you use very short naming e.g. a variable as a, you will forget yourself, what that variable is meant for after sometime. This becomes more problematic in bigger programs. Though I don't see an issue in using getAmt() in place of getAmount(), but definitely getPlayerWithMostGoals() is preferable over something like getPlayer().
Long names, short names, it all depends. There are a lot of approaches and discussions but in fact a method's name should reflect its intention. This helps you to further understand the code. Take this example.
public void print(String s)
Nifty name, short, concise... isn't it? Well, actually no if there's no documentation to tell you what do you mean by "Printing". I say System.our.println is a way of printing a string but you can define printing as saving the string in a file or showing it in a dialog.
public void printInConsole(String s)
Now there are no misunderstandings. Most people can tell you that you can read the method's JavaDoc to understand it but... are you going to read a full paragraph to decide if the method you're going to use does what you need?.
IMO, methods should describe at least an action and an entity (if they're related to one). "Long" is also a perception... but really long names make the code hard to structure. It's a matter of getting the proper balance.
As a rule of thumb, I'd void abreviations and use JavaDoc to further describe a method's intention. Descriptive names can be long but the reward is both readability and a self-explainatory code.
Sometime ago, I remember being told not to use numbers in Java method names. Recently, I had a colleague ask me why and, for the life of me, I could not remember.
According to Sun (and now Oracle) the general naming convention for method names is:
Methods should be verbs, in mixed case
with the first letter lowercase, with
the first letter of each internal word
capitalized.
Code Conventions of Java
This doesn't specifically say that numbers can't be used, although by omission you can see that it's not advised.
Consider the situatiuon (that my colleague has) where you want to perform some logic based on a specific year, for instance, a new policy that takes affect in 2011, and so your application must act on the information and process it based on it's year. Common sense could tell you that you could call the method:
boolean isSessionPost2011(int id) {}
Is it acceptable to use numbers in method names (despite the wording of the standard)? If not, why?
Edit: "This doesn't specifically say that numbers can't be used, although by omission you can see that it's not advised." Perhaps I worded this incorrectly. The standard says 'Methods should be verbs'. I read this to say that considering a number is not a verb, then method names should not use numbers.
The standard Java class library is full of classes and methods with numbers in it, like Graphics2D.
The method seems ... overly specific.
Couldn't you instead use:
boolean isSessionAfter(int id, Date date)
?
That way the next time you have a policy applied to anything after a particular date, you don't need to copy-paste the old method and change the number - you just call it with a different date.
Sure, it's acceptable to use numbers in method names. But as per your example, that's why it's generally frowned upon. Let's say that there is now a new policy in place for the year 2012. Now, there's a new policy in place for 2014. And maybe 2020! So, you have four methods that are roughly equivalent.
What you want isn't a boolean but rather a strategy to do something, or do nothing, based on whether or not a policy was found. Hence, a method void processPolicy(Structure yourStructure); would be a better approach - now you can shield that you're doing a lookup based on the year, and don't have to have separate methods per year, or even limit it to just one policy per year (maybe a policy takes place in two different years, for example, or just three months).
The Java Language Specification seems fairly specific on this topic:
3.8 Identifiers
An identifier is an unlimited-length sequence of Java letters and Java digits, the first of which must be a Java letter.
...
The Java letters include uppercase and lowercase ASCII Latin letters A-Z (\u0041-\u005a), and a-z (\u0061-\u007a), and, for historical reasons, the ASCII underscore (_, or \u005f) and dollar sign ($, or \u0024). The $ character should be used only in mechanically generated source code or, rarely, to access preexisting names on legacy systems.
The "Java digits" include the ASCII digits 0-9 (\u0030-\u0039).
This doesn't specifically say that numbers can't be used, although by omission you can see that it's not advised.
I certainly wouldn't read the Java Style Guide that way. And judging from numerous examples in the Java class libraries, neither do they.
I guess the only caveat is that the JSG recommends use of meaningful names. And the corollary is that you should only use numbers in identifiers when they are semantically meaningful. Good examples are
"3D",
"i18n" ( == internationalization ),
"2020" (the year),
"X509" (a standard), and so on.
Even "int2Real" is meaningful in a folksy way.
UPDATE
#biziclomp has raised the case of LayoutManager2, and claims that the 2 conveys no meaning.
Here's what the javadoc says about the purpose of this interface:
This minimal extension to LayoutManager is intended for tool providers who wish to the creation of constraint-based layouts. It does not yet provide full, general support for custom constraint-based layout managers.
From this, I would say that the 2 in the name is meaningful. Basically, it is saying that you can view this as a successor to LayoutManager. I guess that could have been said in words, but see the examples above on how numbers where numbers are used as short-hand.
# BlueRaja writes:
The 2 does not explain anything - how is LayoutManager2 any different from LayoutManager?
The advice of the Style Guide is NOT that names should explain things. Rather, it advises that they should be meaningful. (For the explanation, refer to the javadoc.) Obviously meaningfulness is relative, but there is a practical limit on the amount of information you can put into an identifier before it becomes hard to read and hard to type.
My take is that the identifier should remind the reader what the meaning of the thing (class, field, method, etc) that is named.
It is a trade-off.
Methods should be verbs, in mixed case with the first letter lowercase, with the first letter of each internal word capitalized.
This phrasing alone already shows that they use a more general meaning of verb than the usual, where only is would be the verb, neither session nor post are verbs. The sentence means something like Method names should be verbs or verbal phrases, ..., and numbers can very well be parts of verbal phrases.
The idea is that a complete method call can be read as a complete sentence, with the subject being the object before the dot, the verb being the method name, and additional objects being the arguments to the method:
if (buffer.isEmpty())
buffer.append(word);
(Most such sentences would be either questioning or imperative ones.)
Your method name has (from a naming convention viewpoint) the only problem that the subject of the sentence (the session) is not the this object of your method, but an parameter, but this can't be avoided with Java, I think (please someone prove me wrong).
For multiple-parameter methods the smalltalk approach would work better:
"Hello" replace: "e" with: "x"
(where replace:with: is one method of the string class.)
Yes, in some circumstances. For example, maybe you want to handle X.509 certificates. I think it would be perfectly acceptable to write a method called handleX509Certificate.
The only problem I see with using numbers in method names is that it may be an indication that something in your design could be improved upon. (I hesitate to say "is wrong.") For instance, in your example, you stated that you have a specific policy which comes into effect after 2011. However, having a method specifically to check for that year seems overly specific and magic-number-y. I'd instead suggest creating a generalized function to check if an event occurred after a specified date as Anon suggested.
(Anon's answer popped up while I was halfway through mine, so my apologies if it seems like I'm just duplicating what he said. I felt that mine expanded on what he was saying a bit, so I thought I'd post it anyway.)
I would consider calling your method something else. Nothing against numbers exactly, but what happens if the project slips it release date? You'll have a method called post2011 - when it should be called post2012 now. Consider calling it postProjNameImplentation instead maybe?
The use of number it is not bad itself, but usually they are not very common.
in the specific case, I don't think isSessionPost2011(int id) {} is a good name. but it is better isSessionPostYear(int id, int year) {} more extensible for future uses.
The fact it is a coding convention and the use of the verb "should" suggest you that digits are permitted but advised against in methods names. However in your example, why not generalizing the same code as?
session.isPostYear(int year);
We use 'em all the time, like the example you showed. Also for interface versions, like IConnection2 and IConnection3.
Eclipse doesn't complain that it's a nontraditional name, either. :)
But acceptable? That's kind-of up to you.
Don't ever forget - rules are made to be broken. The only absolute should be that there are no absolutes.
I don't believe there's a per se reason to avoid numbers in identifiers, although in the case you describe, I don't know that I'd use it. Rather, I'd name the method something like boolean isPolicyXyzApplicable(int id).
If this is a policy that's expected to change more over time, consider splitting policies out into different classes so you don't end up growing a long vine of if(isPolicyX) ... else if(isPolicyY) ... else if(isPolicyZ) ... in your methods. Once this is factored out, use an abstract or interface method Policy.isApplicableTo(transaction) and a collection of Policy objects to determine what to do.
As long as you have a reason for using numbers, then imho I think it's fine.
For your example, there might be 2 isSessionPost method, so how would you name them? isSessionPost and isSessionPost2? Not very clear to be honest.
Just remember that all names must be meaningful and you won't go wrong.
I think in your case it's OK to use it as a one-off marker, specifically if you expect that the method will only live for a short period of time and eventually be deprecated.
If I understand your use case, you need to bring in some legacy data into the new version of your application. If this is the case, then definitely add this method, mark it #deprecated and retire it when all your clients are updated.
On the other hand Ralph here has a valid point. Don't let this project to slip into 2012 :)
nothing is wrong
String int2string(int i)
User findUser4Id(long id)
void startHibern8();
wow! this website doesn't like these method names! I got captchaed!
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In the last weeks I've seen some guys using really long names for a Method or Class (50 characters), this is usually under the premise that it improves readability, my opinion is that a long name like this is an indicator that we are trying to do a lot or too much in a method class if we need such a long name, however I wanted to know what do you guys think about it.
An Example is:
getNumberOfSkinCareEligibleItemsWithinTransaction
A name in Java, or any other language, is too long when a shorter name exists that equally conveys the behavior of the method.
Some techniques for reducing the length of method names:
If your whole program, or class, or module is about 'skin care items' you can drop skin care. For example, if your class is called SkinCareUtils,
that brings you to getNumberOfEligibleItemsWithinTransaction
You can change within to in, getNumberOfEligibleItemsInTransaction
You can change Transaction to Tx, which gets you to getNumberOfEligibleItemsInTx.
Or if the method accepts a param of type Transaction you can drop the InTx altogether: getNumberOfEligibleItems
You change numberOf by count: getEligibleItemsCount
Now that is very reasonable. And it is 60% shorter.
Just for a change, a non-subjective answer: 65536 characters.
A.java:1: UTF8 representation for string "xxxxxxxxxxxxxxxxxxxx..." is too long
for the constant pool
;-)
I agree with everyone: method names should not be too long. I do want to add one exception though:
The names of JUnit test methods, however, can be long and should resemble sentences.
Why?
Because they are not called in other code.
Because they are used as test names.
Because they then can be written as sentences describing requirements. (For example, using AgileDox)
Example:
#Test
public void testDialogClosesDownWhenTheRedButtonIsPressedTwice() {
...
}
See "Behavior Driven Design" for more info on this idea.
Context "...WithinTransaction" should be obvious. That's what object-orientation is all about.
The method is part of a class. If the class doesn't mean "Transaction" -- and if it doesn't save you from having to say "WithinTransaction" all the time, then you've got problems.
Java has a culture of encouraging long names, perhaps because the IDEs come with good autocompletion.
This site says that the longest class name in the JRE is InternalFrameInternalFrameTitlePaneInternalFrameTitlePaneMaximizeButtonWindowNotFocusedState which is 92 chars long.
As for longest method name I have found this one supportsDataDefinitionAndDataManipulationTransactions, which is 52 characters.
Never use a long word when a diminutive one will do.
I don't think your thesis of "length of method name is proportional to length of method" really holds water.
Take the example you give: "getNumberOfSkinCareEligibleItemsWithinTransaction". That sounds to me like it does just one thing: it counts the number of items in a transaction that fall into a certain category. Of course I can't judge without seeing the actual code for the method, but that sounds like a good method to me.
On the other hand, I've seen lots of methods with very short and concise names that do way to much work, like "processSale" or the ever popular "doStuff".
I think it would be tough to give a hard-and-fast rule about method name length, but the goal should be: long enough to convey what the function does, short enough to be readable. In this example, I'd think "getSkinCareCount" would probably have been sufficient. The question is what you need to distinguish. If you have one function that counts skin-care-eligible items in transactions and another that counts skin-care-eligible items in something else, then "withinTransactions" adds value. But if it doesn't mean anything to talk about such items outside of a transaction, then there's no point cluttering up the name with such superfluous information.
Two, I think it's wildly unrealistic to suppose that a name of any manageable length will tell you exactly what the function does in all but the most trivial cases. A realistic goal is to make a name that gives a reader a clue, and that can be remembered later. Like, if I'm trying to find the code that calculates how much antimatter we need to consume to reach warp speed, if I look at function names and see "calibrateTransporter", "firePhasers", and "calcAntimatterBurn", it's pretty clear that the first two aren't it but the third one might be. If I check and find that that is indeed the one I'm looking for, it will be easy to remember that when I come back tomorrow to work on this problem some more. That's good enough.
Three, long names that are similar are more confusing than short names. If I have two functions called "calcSalesmanPay" and "calcGeekPay", I can make a good guess which is which at a quick glance. But if they are called "calculateMonthlyCheckAmountForSalesmanForExportToAccountingSystemAndReconciliation" and "calculateMonthlyCheckAmountForProgrammersForExportToAccountingSystemAndReconciliation", I have to study the names to see which is which. The extra information in the name is probably counter-productive in such cases. It turns a half-second think into a 30-second think.
I tend use the haiku rule for names:
Seven syllable class names
five for variables
seven for method and other names
These are rules of thumb for max names. I violate this only when it improves readability. Something like recalculateMortgageInterest(currentRate, quoteSet...) is better than recalculateMortgageInterestRate or recalculateMortgageInterestRateFromSet since the fact that it involves rates and a set of quotes should be pretty clear from the embedded docs like javadoc or the .NET equivalent.
NOTE: Not a real haiku, as it is 7-5-7 rather than 5-7-5. But I still prefer calling it haiku.
Design your interface the way you want it to be, and make the implementation match.
For example, maybe i'd write that as
getTransaction().getItems(SKIN_CARE).getEligible().size()
or with Java 8 streams:
getTransaction().getItems().stream()
.filter(item -> item.getType() == SKIN_CARE)
.filter(item -> item.isEligible())
.count();
My rule is as follows: if a name is so long that it has to appear on a line of its own, then it is too long. (In practice, this means I'm rarely above 20 characters.)
This is based upon research showing that the number of visible vertical lines of code positively correlates with coding speed/effectiveness. If class/method names start significantly hurting that, they're too long.
Add a comment where the method/class is declared and let the IDE take you there if you want a long description of what it's for.
The length of the method itself is probably a better indicator of whether it's doing too much, and even that only gives you a rough idea. You should strive for conciseness, but descriptiveness is more important. If you can't convey the same meaning in a shorter name, then the name itself is probably okay.
When you are going to write a method name next time , just think the bellow quote
"The man who is going to maintain your code is a phyco who knows where you stay"
That method name is definitely too long. My mind tends to wander when I am reading such sized method names. It's like reading a sentence without spaces.
Personally, I prefer as few words in methods as possible. You are helped if the package and class name can convey meaning. If the responsibility of the class is very concise, there is no need for a giant method name. I'm curious why "WithinTransaction" on there.
"getNumberOfSkinCareEligibleItemsWithinTransaction" could become:
com.mycompany.app.product.SkinCareQuery.getNumEligibleItems();
Then when in use, the method could look like "query.getNumEligibleItems()"
A variable name is too long when a shorter name will allow for better code readability over the entire program, or the important parts of the program.
If a longer name allows you to convey more information about a value. However, if a name is too long, it will clutter the code and reduce the ability to comprehend the rest of the code. This typically happens by causing line wraps and pushing other lines of code off the page.
The trick is determining which will offer better readability. If the variable is used often or several times in a short amount of space, it may be better to give it a short name and use a comment clarify. The reader can refer back to the comment easily. If the variable is used often throughout the program, often as a parameter or in other complicated operations, it may be best to trim down the name, or use acronyms as a reminder to the reader. They can always reference a comment by the variable declaration if they forget the meaning.
This is not an easy trade off to make, since you have to consider what the code reader is likely to be trying to comprehend, and also take into account how the code will change and grow over time. That's why naming things is hard.
Readability is why it's acceptable to use i as a loop counter instead of DescriptiveLoopCounterName. Because this is the most common use for a variable, you can spend the least amount of screen space explaining why it exists. The longer name is just going to waste time by making it harder to understand how you are testing the loop condition or indexing into an array.
On the other end of the spectrum, if a function or variable is used rarely as in a complex operation, such as being passed to a multi-parameter function call, you can afford to give it an overly descriptive name.
As with any other language: when it no longer describes the single action the function performs.
I'd say use a combination of the good answers and be reasonable.
Completely, clearly and readably describe what the method does.
If the method name seems too long--refactor the method to do less.
It's too long when the name of the method wraps onto another line and the call to the method is the only thing on the line and starts pretty close to the margin. You have to take into account the average size of the screen of the people who will be using it.
But! If the name seems too long then it probably is too long. The way to get around it is to write your code in such a way that you are within a context and the name is short but duplicated in other contexts. This is like when you can say "she" or "he" in English instead of someone's full name.
It's too long when it too verbosively explains what the thing is about.
For example, these names are functionally equivalent.
in Java: java.sql.SQLIntegrityConstraintViolationException
in Python/Django: django.db.IntegrityError
Ask yourself, in a SQL/db package, how many more types of integrity errors can you come up with? ;)
Hence db.IntegrityError is sufficient.
An identifier name is too long when it exceeds the length your Java compiler can handle.
There are two ways or points of view here: One is that it really doesn't matter how long the method name is, as long as it's as descriptive as possible to describe what the method is doing (Java best practices basic rule). On the other hand, I agree with the flybywire post. We should use our intelligence to try to reduce as much as possible the method name, but without reducing it's descriptiveness. Descriptiveness is more important :)
A name is too long if it:
Takes more than 1 second to read
Takes up more RAM than you allocate for your JVM
Is something absurdly named
If a shorter name makes perfect sense
If it wraps around in your IDE
Honestly the name only needs to convey its purpose to the the Developers that will utilize it as a public API method or have to maintain the code when you leave. Just remember KISS (keep it simple stupid)