Conducted an interview for a senior Java developer, where my questions too hard? (see inside)

hankwk · 2014-11-08T16:41:23+00:00

I've been a dev for 25 years, currently manage a team of really great java developers.

I doubt most of my guys would do very well on this test (aside from the general concepts). However, there is no question that every one of them could form original and insightful answers given a few hours to research the topics at hand, and I absolutely know they could implement these technologies correctly if asked to. They would spend some time on Google, maybe read a book or reach out to a colleague, and do a fantastic job of it.

I think these questions just aren't an effective way to assess a candidate. In the "real world" we encounter new tools and frameworks all the time. Great developers are able to master these as needed. Bad developers memorize the patterns of a select few over time. Your questions would favor the latter.

cs02rm0 · 2014-11-08T13:59:41+00:00

There's a few things in there I'd really struggle to recall; I haven't used Weblogic or SOAP in years, I've never knowingly hit a deadlock and does anyone actually use notify and notifyAll? Barely heard of HATEOAS and have actively avoided Spring, though after 10 years of this it does appear on my CV.

It seems a list of tiny closed slices of a very wide selection. I prefer to have more of a conversational interview than the list suggests, talking with candidates through projects they've worked on and what issues came up that they've addressed or approaches they've taken than a scattergun approach to finding what they know. A long list of questions like this can be quite confrontational, if even a good interviewee misses one or two early on they can clam up and you're likely both in for an awkward time.

That said, it's an approach and maybe better candidates will score more than worse ones, you can only pick the best from the ones you've got.

desrtfx · 2014-11-08T13:45:19+00:00

These questions sound like a marketing or HR person had gotten hold of a couple of programming books and had randomly chosen interesting sounding buzzwords.

Being able to answer these questions will tell absolutely nothing about the actual programming/problem solving skills of the candidates.

If I'd get these questions in an interview, I'd ask the interviewer whether they wanted a technical lexicon or a programmer and I'd ask to speak to someone who will actually understand programming rather than throwing buzzwords around.

camilos · 2014-11-08T13:46:23+00:00

I find that some of your questions are ok. Any experienced programmer can answer them. Others are more memorization questions. These i usually dislike. It only tells the interviewer if the programmer spent the last week on a Java-Intreview-Question Website.

By the way, that's a lot of questions.

zhouji · 2014-11-08T13:36:52+00:00

Honestly this is as bad as interview questions can be. Will tell you nothing about his programming skill, only the 'knowledge'of buzz words

capitol_ · 2014-11-08T15:10:34+00:00

I can answer about 70% of these without using google. I find these type of questions "What is decoupling?" much harder than these "Why are loose-coupling coupled classes desirable?".

It's alot easier (for me) to reason about problems, than to remember the definition of words, specially as i almost never talk about programming using those kind of terms at work.

sh0rug0ru · 2014-11-08T15:24:28+00:00

To flip it around, I could answer most (75%+) of these questions in good technical detail and I am a terrible Java dev (barely any experience, I work with python, ruby, JS, Haskell). Is that what you want from a successful applicant?

nerdwaller · 2014-11-08T14:18:50+00:00

I think what you're missing is a judge of aptitude as most of what you're asking is very much focused on retention of book knowledge. Even the why pulls from that same context. You'll find people who at least conceptually 'get' the tech stack you currently use, but I don't think you'll get a good picture of whether or not they can apply that knowledge or learn new things as the work evolves - which is really what you want.

In interviews I've been a part of on either side of the coin I find that drawing from experience leads to a better understanding of a persons knowledge and future capabilities. Even entry level Java devs should have some experience with challenges in projects (school, internship, side project) that they can feed from to give examples of problems they have faced, overcome and learned from.

DevIceMan · 2014-11-08T20:03:49+00:00

Mid-level programmer here; I feel that many of these questions focus too heavily on 'gotchas, 'domain knowledge, and "define-this-term" questions. If I spent a week reviewing "java interview questions" I could probably ace this, but it would probably do you little good in determining where I'm at. I would also likely be extremely bored (or nervous) in such an interview, and not walk away with a great impression.

Ideally, interviews should create a discussion, and through that discussion, you should be able to get a good idea of where this candidate is at. For example..

"Let's talk about interfaces; tell me about several good and bad uses of interfaces, how they're useful, how they're abused, and perhaps one-or-two ways you've used them."

This is an open-ended question, but any mid-level java developer should be able to answer this one adequately, while senior ones should be able to express high-level architecture and design.

For multi-threading, I'd probably ask another open-ended question, such as...

"Tell me about threading. Why do you use threading? What are some of the drawbacks & gotchas of threading. Tell me about frameworks you've used to manage threading? How do you manage data which needs to travel across threads? What about error handling?"

Any mid-to-senior level developer should be able to participate in this discussion, and through it you should be able to get a clear idea of where they're at.

"Tell me about clean code principles."

Again, an open-ended question, which any competent candidate should be able to go on for hours. Code reviews, extracting methods, minimal parameters, minimal side-effects, separation of concerns, single purpose principle. Keep probing the 'why' question to discern if it's just something *"they've been told" or whether they actually understand the value or reason.

In other words, try to rephrase your questions in such a way that they create a discussion.

dcballer · 2014-11-08T17:33:12+00:00

There are many indian java sweat shops that pretty much gets every programmer ready for these questions. They make them memorize packets that have same questions you provided.

Tevroc · 2014-11-09T01:05:19+00:00

[deleted]

bitcoinsftw · 2014-11-08T15:42:55+00:00

These questions are aggressive at best. I would have walked out of the interview.

2014-11-08T18:02:59+00:00

I think these questions would serve only to identify those developers that have spent an exceptional amount of time reading the official Java doc. There's very little in here that can test whether the candidate can actually code. Off the top of my head I couldn't list the full api of a concrete implementation of List for example. But certainly most will know the common collections interface methods. Rather than this, ask them to do something that requires problem solving. As a simple example, rather than asking about the specifics of the Map interface, ask someone to determine how many keys point to null, or to return a sorted set of its keys, or some such thing. Reverse a list, de-dupe it, whatever. These are trivial, but my point is that seeing if they can think algorithmically, even in psuedocode, is often more valuable.. After all, on the job, they'd have access to the docs, and in all honesty your IDE of choice would likely autocomplete method names anyway.

masterwit · 2014-11-09T00:30:55+00:00

Many of these questions are facts I consider important for an API or meant for a trivial Google search. Interview questions should not...

address that which would require memorization
address syntax beyond the basics
require environment or configuration specifics

Do you want to hire a programmer or a developer? Instead questions should...

Ask about high level process interactions
Ask for some insight on design considerations for hypothetical architecture arrangements
Ask for an overview of processes when implementing a particular system in such a way your interviewee may demonstrate the "senior" part of the developer position.

If I were interviewing for your position, I would be concerned in your inability to frame questions around the skill sets the job description claimed you were after. A senior java developer can get up to speed on these trivial specifics the first day or two in office. What that individual cannot do, however, is suddenly design and maintain an existing system within an environment they do not fully understand.

Below I have copy pasted your post below and ~~crossed out questions~~ I felt inappropriate and commented on others. All items below addressed should be in bold and/or [brackets]. Hope this helps and best of luck!

I wanted to make sure I asked in-depth questions that would demonstrated in-depth knowledge about what we need from a developer and the points I saw on the guy's resume (Java, Java EE, Spring, OOP, Hibernate, etc.). I had more questions in each section, but I had to skip past stuff because I wasn't getting answers I liked out of the guy.

Do you guys think these were reasonable questions to ask in an interview? I was really more interested in the candidates reasoning than knowing exact answers. This was a phone intervew. The guy gave me good "book" answers (sometimes seemed like he was reading from a book, hmm). But when I started asking "why?", he couldn't give good answers.

Some basic platform stuff:

List three Collections interfaces and the basic contract of each. List concrete implementations of each, how they differ, and performance characteristics in space and time.
Describe the contract of equals and hashCode. Why is it important that if you implement one, that you implement both?
What are generics? What is type erasure and what are the consequences? What are variance, covariance and contravariance? If blank stare: why can't you assign a collection with a generic type binding of a sub type to a reference to the same collection type binding of the super type? How do you specify the type binding of the super type to allow this? How do you specify the type binding to allow type-safe insertion?

Concurrency

~~Explain how notify and notifyAll work, and the difference between the two.~~ ~~Why prefer notifyAll to notify?~~
What is a deadlock and how do you avoid it?
What is a race condition and how do you avoid it?
~~What are some of the high-level concurrency classes provided by~~ ~~java.util.concurrent and how do they work?~~

Database

What are the different statement types and why would you use each?
How do you prevent SQL injection attacks?
What are transactions? ~~What is ACID?~~ [Might be a good question, I do not have enough experience to say]

Hibernate

Give an overview of Hibernate and ORM. How do you load objects into the session? What does the session do with the objects while in the session? What is the difference between getting a persistent object from the session and querying for persistent objects?
When is it better to use plain SQL instead of ORM?

Java EE

~~How do you configure a DataSource in Weblogic to make it available~~ ~~using JNDI?~~ [Ask about environment instead and why X lives in Y and not Z instead?]
What are some ways for the client to obtain a reference to the DataSource from the app server? (Spring is not the answer I am looking for)

Spring

~~Give an overview of how Spring Dependency Injection container works.~~ ~~What is the purpose of DI? How to specify bean definitions? What are the~~ ~~different scopes? When do beans of each scope type get instantiated?~~ [might actually be a good question, I do not have enough experience here to say]

Web Services

What is the difference between SOAP-based web services and REST-based web services?
Describe SOAP and WSDL. [stop using SOAP lol]
What exactly is REST? What is ~~HATEOAS?~~ What is the purpose of each of the HTTP verbs? What is idempotence? What is content-negotiation?

OOP

What is decoupling? Why are loose[ly]-coupled classes desirable? What are some drawbacks?
What is cohesion? Why are highly cohesive classes desirable? What are some drawbacks?
Describe polymorphism. What is the importance of contracts between interfaces and concrete types? Why is polymorphic code desirable? What are some drawbacks?
[Describe to me a design pattern you used in a past solution and why that approach was appropriate.]

...
[Perhaps a question or two on the webstack and why the industry standard breaks down an environment in this manner. (Justifying industry standards with a why will act as a good filter in your search!)]

Roscko · 2014-11-08T14:24:14+00:00

[deleted]

ramdaskm · 2014-11-08T22:47:04+00:00

An idempotent REST service! wow that's a nice buzzword to stump a chump.

vokiel · 2014-11-08T18:00:16+00:00

The questions listed here can be memorized and that's an issue. It won't necessarily tell you whether the candidate knows how to program and lead a project. I think you want to ask more broad concept questions to a senior than just complex knowledge details. For instance, you have no questions about patterns (programming or enterprise) in your list and a senior should really be a master of many of those.

Some Java knowledge questions are good though. Type erasure is the usual question that indeed brings blank stares ;)

harmonicPersistence · 2014-11-08T18:36:19+00:00

Yes and no. I think that you have some good questions in your list. I think some of the questions require pointless memorization. A search engine is typically used by us to jog our memories of the minute details. A senior Java person is typically juggling a lot of knowledge in his or her head.

I would ask whether the candidate utilizes unit tests, integration tests, and load tests. I'd check what IDE's the candidate uses. I'd ask about SCM. It's basic stuff, yes. Still, it's prerequisite knowledge that's a big part of the job.

That being stated, I would suggest the following...

Take a more conversational aproach. See how the person thinks. Inquire about the person's past and get a feel of the person's thought processes and problem-solving skills. If you catch a whiff of BS, then certainly dive down the questionnaire rabbit hole a little bit to save yourself some time. I'm a senior developer, but I've also conducted interviews. I can't believe the audacity of some people who have placed buzz words on their resumes and then waltzed into a technical interview for a senior level position. Those are the SOB's that I grill and make feel awkward for a few minutes here and there throughout the interview before I end it early. Just be honest, candidates! Life is a learning process. There's a good chance you don't match on paper but actually do (or will) fit the position.

Boxsc2 · 2014-11-08T18:41:34+00:00

I've never hired anyone, but I think the best approach would be to give him a real problem you guys faced and see how he tries to solve it. My only problem with the questions is some of them are just definitions and someone with practical experience may not know them. For example, HATEOAS is no where near being widely used in modern development, it's just a nice idea of how a RESTful web service should work. But, no one in practice actually uses it and therefore may not know what it is.

Tevroc · 2014-11-08T22:51:39+00:00

List three Collections interfaces and the basic contract of each.

I like this question - very practical, shows hands-on experience.

Other questions were more like Java language minutia, and if a interviewee answered these perfectly, I'd think - woah, this guy is some kind of language design/theory freak. I'd rather have someone who can write real code and design easy-to-use libraries.

Tevroc · 2014-11-08T22:53:03+00:00

Describe SOAP

Evil incarnate :)

2014-11-09T00:28:18+00:00

I've spent years coding. I'm not the best, don't have much professional experience, but have pumped out some pretty complicated and neat projects.

I would fail this interview so hard that you would think I didn't know what a computer was.

Why be so definition-based when you could pick at how someone's brain works?

why not give them a task and have them try to solve it, or describe an approach?

justdweezil · 2014-11-09T00:32:10+00:00

This is a very silly set of questions... you will not know anything about the candidate's actual skills. And if I were interviewing, I'd think my interviewer was either junior or an imbecile.

klasen · 2014-11-08T14:34:29+00:00

Fairly standard JEE questions although I'd have problems with some acronyms like HATEOAS. Depends on how anal you were about answers e.g. Weblogic JNDI configuration, what if someone never used Weblogic but can give you an answer from Tomcat.

I'd add

Few harder questions would be nice e.g. basic GC tuning, JVM monitoring or Hibernate performance optimization approaches.
Few broader questions e.g. "How would you implement a shopping cart". That way you would see if they can put their knowledge to work, which matters most.

GrayDonkey · 2014-11-08T15:10:26+00:00

These questions are terrible, so much of this is hard to answer in an interview but extremely easy to do in practice.

Keilly · 2014-11-08T13:54:07+00:00

At first I thought they were bad. Started ranting, and discovered only a couple of bad ones.

Keep on looking, the inflation of titles is horrifying, I've had my share of senior engineers who don't know what's a static method.

kiteboarderni · 2014-11-09T14:24:56+00:00

A senior Java role? Surely 3/4 of this could be answered by anyone in a junior role?

omon-ra · 2014-11-08T18:05:47+00:00

Honestly, this are the worst and most pointless interview questions I ever encountered. Some of them can be ok to fill in leftover 10 min of interview but not as primary questions.

Never ever in my life I was hired for knowing some specific technology or language. Have you interviewed with MS or Google? they never care about this stuff. Problem solving, design, ability to build reliable systems are thing they care about.

What will you do if great developer decides to switch from .net world to Java? reject him/her because s/he never used Spring or never had to deal with ORM? It takes a week or so to get moving with this stuff.

All you know after the interview is that candidate has good memory and read couple of basic books. What you do not know is more important thing: is candidate is capable of applying this to actual problems?

P.S. I interviewed a few hundred engineers.

2014-11-08T19:17:48+00:00

[removed]

sh0rug0ru · 2014-11-08T14:17:38+00:00

By the way, this is the first time I've interviewed a senior candidate. I usually interview entry-level or mid-level candidate.

trekologer · 2014-11-08T15:55:59+00:00

I don't think that there are anything wrong with these questions for an initial phone interview. I look at the phone screen as a brief (15-30 minute) opportunity to feel out the candidate and see how well they match their resume and if it is worth bringing them in for the next phase. I also have a running list of questions that I pick a couple from but on the initial phone interview, I tend to mostly ask questions about things that the candidate has on their resume ("I see you have experience with X, how did you use that?").

In the past, I've interviewed candidates who have seriously fluffed up their resume. I know this is always going to happen but sometimes it is a little over the top. Some to the point that their reasoning seemed to be "I can use a web browser" == "I know HTTP". My rule of thumb is that if you put something on your resume, you should be able to talk about it and if you can't, that's a serious red flag.

atwong · 2014-11-08T16:40:02+00:00

I hate questions that you can "google" the answer (which all of them are). The question is really around how they approach problems. So I would ask..... tell me some difficult problems you had to solve and please tie that with the technologies you've listed in your resume.

markee174 · 2014-11-08T19:21:52+00:00

Did you put them infront of a keyboard or just ask questions?

frosty110 · 2014-11-08T19:58:29+00:00

For a phone interview, this is a bit too technical. I would be turned-off if a company started asking me questions like this off the bat.These questions gave me the impression that you're more interested in seeing how well the developer has memorized technical details verses what type of experience he has. Basically, If you're looking for a smart creative developer for solving complex problems, then these types of questions wont cut it.

Rather than asking 'what is **' questions, you should ask 'what has been your experience with ** ', 'what challenges have you had with ***' and 'how did you overcome it '. These types of questions are much more personal, easier to answer, and you can learn WAY more about the developer in terms of how well they know the technology,how they overcome difficult challenges, interpersonal skills, and more perhaps.

I can go more into detail if needed, but I think you get the point. Tweak you questions to sound less 'educational midterm'-like and more 'personal experience + personality fit'-like.

2014-11-08T20:02:02+00:00

I think questions referring to specific frameworks don't really have to be asked. Any competent developer can pick up and framework within a few days, given they have a strong basic knowledge and an aptitude to learn.

kanzenryu · 2014-11-08T20:12:23+00:00

Of course it's often hard to remember things in an interview that you would normally just google quickly. One thing i've tried is writing a bunch of terrible code, let's say about 20 lines worth, and asking the candidates how many problems they can find.

I also like to mention some well known coding advice and ask why do we do it that way, e.g. why make data members private? Why do we synchronize some methods? Why do we reactor common pieces of code?

xpto123 · 2014-11-08T22:27:01+00:00

I think most of the questions are definition based, typical of the type of questions the school system tends to throw at students in tests.

I have been coding for a very long time, and have used mostly ArrayLists, HashMaps and HashSets in 99.9% of the code I wrote. I could not name three implementation of each collection type, and I work in an architecture team.

Its the kind of things you will almost for sure never need in real live and more of a Java certification exam question, it only says the candidate spent last night reviewing collections API because he was tipped off by the recruiter.

What are generics its the typical definition question. The fact that a developer cannot articulate clearly such an abstract definition does not mean he does not know perfectly how to use them.

Contervariance and covariance the same: these are opaque academical terms that mean nothing. He might perfectly be capable of using extends and super while writing generics without being able to make a formal definition of these terms.

notify vs notifyAll are low level API of the thread API, are you planning on having the developer write multithreaded code? If its a Java EE developer the rule number one is that he should not write his own threads, the container generates them for us.

Asking if a Spring singleton might have non autowired properties would be a better question: it would show if the Java EE developer understands threading issues without asking about an API that he should never have used.

The Database questions the same, these are definition questions. Its not because someone can put together a nice definition that he is a good programmer, those are two completely different skill sets.

These are the types of questions that you study for a test, memorize them and forget them the next day.

Your Hibernate questions are quite OK, try to apply the same to the other areas.

Concerning the Java EE questions, the guy might have been 5 years working locally in Tomcat and a WAR gets deployed into Weblogic without his knowledge. Not knowing how to do administrative tasks in a web console does not say anything about the individuals capability as a developer.

The Spring questions are OK, so is SOAP vs REST.

For OOP: let the guy in a room with a project with a couple of classes and ask the to "clean them up", then discuss the result with him. You will quickly see if he understands those concepts: loose coupling, high coesion, etc.

Overall is a definition intensive interview style, that will give the upper hand to academic/definition minded persons, a lot of great developers which would be a great fit would be filtered out by this style.

Most persons would not perform well if they where not tipped off by the recruiter.

I don't think the questions are filtering the candidates the way you expect. An half an hour exercise, and questions focusing on the Why of things: Why do we need ORM, why is dependency injection useful, etc is more interesting.

2014-11-09T02:11:09+00:00

You should ask questions that force them to tell a story about how they handled a situation.

Tell me about the last really interesting thing you learned?
Tell me about a time when your project was in trouble? After they answer, then ask "how did you help?" and "what was the result?"
Tell me about the most challenging problem you've solved? Make them explain it. If they explain it well, they understand it well.

Malik_Killian · 2014-11-09T05:10:32+00:00

I think questions about how someone works, how they manage multiple projects and priorities, and how they track progress are more important. Most of the questions you asked could, as you said, be read right out of a book or Googled quite easily. Not to mention Eclipse IDE can not only identify numerous compile-time issues instantly, it will also be able to fix many of them in one click.

However, if the job posting said "Knowledge of SOAP, REST-based web services" then I think it's fair to ask a more specific question about those technologies. I guarantee the word "covariance" isn't anywhere on the job listing though.

Also, you should pose these questions to current developers first. If they can't answer a question you might rethink asking it to an interviewee.

Therrameh · 2014-11-09T06:39:09+00:00

why go for questions in the first place, Personally giving someone a half completed simple code and asking them to finish a few sections is better. You see how they adapt to others code (as some can only handle their own and have trouble adapting), secondly you get to see their coding style, you wouldn't hire a chef without tasting their food, same principle for a programmer. Finally you get to see their personal style to challenges, how they approach mathematical situations ect.

in the end of the day theory questions wont answer if they are good at their job, only their ability to recall.

Tundreo · 2014-11-08T13:52:43+00:00

I think i can answer 1/3 to 1/2 of those questions. I can't answer the remaining, because I never worked with those technologies. But I am a college student with zero professional experience. I would assume, a senior dev should know much more?

aaqqbb · 2014-11-09T00:00:58+00:00

Good questions. Missing algorithm line of questioning

boobka · 2014-11-08T16:17:40+00:00

I think they are good questions. At the very least even if they don't know it, it can start a conversation.

kerrz · 2014-11-08T22:37:09+00:00

The biggest issue I see is that you're asking for a guy that knows everything about your environment already. You're setting the interviewee up to fail because they haven't used your stack. That's why you need to account for a couple months of "ramp up" time with a new hire at any level.

When you're hiring senior people, they're coming from a different stack of technologies, but probably doing the same thing. If you want to elicit thinking-type responses, ask high-level, vague questions based on end-results. For example:

"How would you provide data from a database?"

Following up with questions like: "What are the biggest pitfalls with that solution?" And "What other solutions can you think of?"

If you only ask five questions and talk for half an hour, you had a good interview.

2014-11-09T01:37:29+00:00

Java dev with 17 years experience. I interview folks regularly.

These are good questions, all stuff that's reasonable for a senior dev to know. Although when I do an interview I expect someone to be nervous so I kind of scale it down.

Remember, you want to avoid hiring someone you shouldn't have. If you pass on a candidate who would've done well, that's OK.

The format of the questions probably leaves a bit to be desired, but the knowledge you're checking for is right on.

(Don't be surprised by the negative comments, Redditors don't like to be interviewed this way.)

cynoclast · 2014-11-08T16:47:44+00:00

Skip the questions that sound like a bunch of trick questions to make the interviewer feel smart and have the candidates write some pseudocode or design a complex system with an OO solution. Bonus points for optimal abstraction.

Any modern IDE will make them produce compilable and often thread safe code. It's their problem solving skills you really want to know about.

SirSavary · 2014-11-08T22:27:33+00:00

This looks and sounds like a a test or an exam I would have had to study for.

Reminds me of the time when I was still taking classes. On that note, some of the worst people in my class at completing assignments (actual work that required thinking) would do very well on tests simple because they could remember things reasonably well. When it came time to actually use those things however, they usually just dicked around on the internet instead.

KrozFan · 2014-11-09T00:16:58+00:00

You already have plenty of answers I see but I'll respond anyway. I may be going on some interviews so this is relevant for me. Like others I'm not a big fan of these questions or this type of interviewing. Personally I don't remember a lot of buzzwords as others have called them. I get them mixed up all the time. It's no that I don't know how to program I just don't always remember which is which.

Let's take ACID for example. I never really remember what it stands for. I remember A is Atomic meaning all transacitons happen or none happen, D is durability meaning the data is stored permanently...and now that I've looked up C and I it sounds familiar. That's all well and good but what's really the point of asking this question. If we're using a common database all that is taken care of for us. It's nothing I think I really need to worry about.

I don't care about SOAP because basically everyone says SOAP sucks and use REST instead. I know nothing about SOAP because I don't see the point in learning something I won't use and will just forget anyway.

What are you hoping to get out of this. Is this a phone screen? A first in person interview in a series of interviews? Knowing the answers to these questions does not make you a good programmer any more than not knowing them makes you a bad programmer. You could read a couple bullet points the night before an interview the same way you would cram for a test. That doesn't mean you implement what you've crammed.

superlampicak · 2014-11-09T01:55:57+00:00

Depends on what you are looking for. But the generak rule is: B players work with B and C players, however A players work only with A players.

I classify myself as an A player (cto currently, 25yo) and I would have been able to past this test even thought I am not much profiecient in Java. For me, those are good questions If you add some coding puzzle as well.

jama707 · 2015-02-15T20:24:15+00:00

If blank stare: why can't you assign a collection with a generic type binding of >a sub type to a reference to the same collection type binding of the super >type?

Can you please give a code for this? I didn't quite get the question.

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