The 2nd Monitor

konijn

20:00

Show this user some love: he already has 2 good answers : codereview.stackexchange.com/a/47883/14625

janos

yup, nice answer

rolfl

Decent, but I worry about the hypodermic link .... in this case it appears innocuous.... and disclaimer has been applied, so OK.

skiwi

@rolfl Do you have some thoughts about Java-8-ifying JDOM yet?

rolfl

I have had thoughts, do you have requirements?

JDOM is a stable product, with 'slow moving' customers.... (banks, etc.).

skiwi

I don't think I can set any requirements, when I'm just glancing at JDOM

rolfl

20:08

It does not have an 'agile' development cycle, but the Java8 changes are significant, and could have a distinct impact on JDOM usage. I need to understand it.

skiwi

btw as a sidestep

rolfl

(what the impact will be).

skiwi

When companies upgrade a component of their software, they will always recompile the code and check for issues, right?

An update in which the API changes*

rolfl

Depends what you mean....

Companies take JDOM as a jar file, they do not compile it.

skiwi

I get that,

rolfl

20:09

They may recompile their code, but not JDOM.

skiwi

But let's say you have a banking program with 30+ jar dependencies, and they update from JDOM 2.0.0 to 2.1.0 (yes, they're lazy people in that company)

rolfl

On the other hand, they may have components that are internally managed as jars anyway...

skiwi

Can you expect a reasonble company to actually recompile all their code?

rolfl

Every major Java product/Project I have worked on has always rebuilt their complete code-base from scratch (not iterative build) for each release.

programmers and some test systems may use an iterative build process, but that can introduce unexpected things, sometimes.

skiwi

But of course developers will not be happy at all if they suddenly see all red lines because some guy decided to remove functionality from an API

rolfl

20:12

Correct.... that will set off alarm bells, and it required JDOM to chang package names from org.jdom.* to org.jdom2.*

Because, when you have complicated projects, some of your dependencies use JDOM 1.x and others use 2.x and you need both sets of API's in your classpath.

skiwi

And I totally understand that you've been fairly recently doing that process and don't want to do it again soon

rolfl

I do not believe there is a need to introduce API/compatibility problems with Java8 support.

(for JDOM).

The Java8 support can be introduced by extending, not changing the current API.

skiwi

I think so aswell, yes

rolfl

(and it will be a no-go to change the current API)

But, I am at the point where I can say that JDOM1 is end-of-maintenance, and that JDOM 2.0.x will support Java and later, and JDOM 2.1.x will support Java8 and later.

skiwi

I have tried out JDOM2 a little bit this afternoon, but found myself busy mostly with making the other bunch of stuff

List<Element> pages = document.getRootElement().getChild("html").getChild("body").getChildren("div");
Stream<Element> filteredPages = pages.stream().filter(predicateByAttribute("class", "ocr_page"));

rolfl

20:16

You should learn XPath.

skiwi

I was thinking as example, it might be nice to have a getChildren(String cName, Predicate<Element> filter)

was just a first thougth I got there

rolfl

Consider ..... getContent(Filter<...> ...)

skiwi

I see

I'd definately need a way closer look to see what could use improvement with Java 8

rolfl

The actual Filter instance can be customized from AbstractFilter: jdom.org/docs/apidocs/org/jdom2/filter/AbstractFilter.html

skiwi

It would be cool to add a Predicate<Element> option wherever there's a Filter now, but then you do have much more options to choose form which may be confusing

rolfl

20:21

But, XPath would still be the standard way ....

XPathExpression<Element> xpe = factory.compile("/html/body/div[@class='ocr_page']", Filters.element());

skiwi

It might be better if I'd have some looks at existing code and see where redundancy is and if it could be fixed somehow

rolfl

List<Element> filteredPages = xpe.evaluate(document);

skiwi

Difference is that you know JDOM like the back of your hand ^^

rolfl

^^^ it helps , yes

skiwi

Are there any full examples available? Which represent a real usecase

rolfl

20:26

Hmmm .... put that way, not that I am aware of that I can share.... let me think about that... Eclipse uses it...

skiwi

I think there's some oppurtunity for internal cleanups

But it might be limited by preserving existing API's

However internal Java 8 can decrease performance, so it's not that trivial either

rolfl

There could well be.... I know I never hit all of it when I revamped everythng in 20012

skiwi

Is there any obvious way to integrate lambdas? Are there places where you'd want them?

rolfl

Internally in JDOM, or as part of the API?

Internally, I don't think it will be necessary.

As part of the API, then exposing streams and being able to process them, seems reasonable.

Out of interest, check: mvnrepository.com/artifact/org.jdom/jdom2/2.0.5

Cisco uses JDOM in their logging.

skiwi

As part of API I meant there

Ah cool, you can see who uses it there

Also lambdas don't imply streams immediatly

Consider List.replaceAll

Though I do not know if there's any direct usecases in inline manipulating Elements

rolfl

20:35

Here's the download Graph for JDOM from maven central repository .....

90% of it is still JDOM 1.x .... because of legacy usage in all sorts of places.

12K downloads per month of JDOM 2.0.5

skiwi

That's a cool number of downloads

rolfl

The thing is, that those downloads are unrelated to actual usage ... for example JDOM 2.0.5 is in both debian, and centos.

skiwi

I'm unfamiliar with Linux and variants, do they all pull during installation?

rolfl

.... I suspect there's millions of people using JDOM all the time.

TheDoctor

Puppy is totally self-contained.

rolfl

20:38

@skiwi No, the way maven works, is that many people will pull it only once, and cache it on their local mirror repository

TheDoctor

(Puppy linux that is)

rolfl

a single download from maven could represent something like "eclipse many versions ", or "Microsoft".

There is no way to know.

skiwi

Ah, I thought you were implying that the actual usage is way lower than the 12K downlaods, but you actually meant the other way around ;)

rolfl

I do know that IBM uses JDOm in many products that are have thousands of installations.

Also, the maven downloads only represent a subset of the actual downloaded content.... there are people who build from source (the linux distro's do), and others who download from jdom.org/downloads/index.html

skiwi

But also not only developers use it, also the customers

rolfl

20:41

Yes, the JDOM gets shipped as part of whatever the developers 'build', and those shipped things are not counted.

skiwi

I've got to go though now, it was an interesting conversation :)

Learned a lot of new things today

rolfl

And.... JDOM is on android too....

who knows how many in there ;-)

skiwi

Well, the regular shipped jars aren't counted, but if someone else dveloped a program that relies on the JDOM dependency. ANd an user installs it and figures out he needs it, then he might still need to pull it himself/herself

Jamal

20:58

It looks like Academia SE has recently graduated.

Stack Exchange

0

Q: Wrote a package in Go. What did I do wrong? What did I do right?

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janos

21:19

was there a fancy name for old-ish questions with no answer?

... and for answering those?

7

Q: Connecting to EC2 instances using the instance name instead of IP

I'm an intensive user of AWS EC2 instances, many instances are launched, stopped, repurposed, etc. To connect to any instance using SSH I must keep track of their IPs. The bash script I wrote (following the question I asked on SO) uses aws-cli to do the heavy lifting for me, leaving me to remem...

bash amazon-ec2

rolfl

zombies, and killers.

janos

ha! thanks @rolfl

rolfl

headshot!

janos

so that was the zombie. And the killer is:

1

A: Connecting to EC2 instances using the instance name instead of IP

It's mostly fine, but I would suggest some minor improvements. Give a proper name to $1 early on, for example: host=$1 if [ -z $host ]; then echo "Please enter machine name" return 1 fi You use it in several places later and it will make the code more readable. These kind of if conditi...

rolfl

technically, 'killer' is not part of the meme...... but, yes, you hunted that zombie, and, it is confusing, because actually my upvote (ammo) killed the zombie, because zombies are questions without an upvoted answer.

Still, you posting the question here is a 'killcam' (come see what I did)

and, the next vote in is the double-tap.

janos

21:26

lol, makes sense ;)

so you're the killer, I'm just the instrument then :p

rolfl

uh-huh.

And, one more vote till the revival.

janos

oh, I thought it takes 3 to revive. that's great

rolfl

I believe we can break out in the revival song now .... any second....

janos

:)

Jamal

Two for Revival and five for Necromancer.

rolfl

21:30

3 is for something else..... 3-down for peer pressure, and 3 up for disciplined.

3 for self-taught too.

janos

hope the OP will like it too

I don't remember seeing him in this room

Stack Exchange

22:52

0

Q: Refactoring & Optimizing Go Code

I'm pretty new to go, and I do not know the best or idiomatic ways to do most of the stuff, so I'd appreciate feedback on how to make my code better, faster or more idiomatic. My program is a set of methods/functions to parse an infix notation expression then convert it to reverse polish notatio...

optimization clean-code go

BlueBug

HI! *just saying

syb0rg

@BlueBug Hello

BlueBug

much joy! to hear voice echo back from depth of internet.

syb0rg

@BlueBug I am autonomous...

Stack Exchange

0

Q: Project Euler 23: Non Abundant Sums

Here is my solution to Project Euler 23: Non Abundant Sums. I know I'm doing the Divisors function brute force, I can't seem to get it to work any other way. Any improvement's are welcome. #include <iostream> #include <vector> //Calculates divisors void Divisors(unsigned number, std::vector<uns...

c++11 programming-challenge

BlueBug

23:01

echo back, I mean, to be answered back by sweet/beautiful internet souls.

syb0rg

Heh, rob0t doesn't have a soul. :P

AwesomeUser

Do either of you know much about python?

syb0rg

@AwesomeUser I don't, but @200_success or @Corbin may be able to help you out.

AwesomeUser

Ok thanks

syb0rg

@AwesomeUser Just ping one of them with your question, I'm sure they'll get back to you eventually (if it isn't too long).

Hey @MattS.

AwesomeUser

23:15

Ok

@200_success @Corbin I am trying to export JSON data out of earthquake.usgs.gov/earthquakes/feed/v1.0/summary/… with python on a RPi and I am running pastebin.com/usTM71KK . I just cannot seem to replace 'type' with something like mag or magType

Stack Exchange

0

Q: Simple event management system. Am I missing something

In an effort to rid my code of jQuery, I wrote a custom global event management/handling system. I was expecting this to be hard as, from what I've read, most people don't create their own. It's far simpler than most libraries I've seen. Is there a flaw in this method? What are the benefits of us...

javascript event-handling

rolfl

@nhgrif - long time... monkey

nhgrif

Yeah.

This guy posted a huge question and didn't leave much of a comment at first... but it did make me feel better when I saw him come back with more comments: codereview.stackexchange.com/questions/46357/…

grovesNL

@AwesomeUser that's because magType is specific to a Feature

nhgrif

Makes it at least seem like he'd been giving the answers some thought

Hey, now I'm one vote away from a Nice Answer!

rolfl

23:34

Sorry, BTDT:

AwesomeUser

How would I run that then?

grovesNL

@AwesomeUser here's a little sample to get you started pastebin.com/UbNsDY9h

AwesomeUser

Ok thanks

grovesNL

@AwesomeUser ie. FeatureCollection -> Feature -> Properties -> magType

Mat's Mug

@rolfl that's killcam... noob (@CallOfDuty, that is - we all know you're a veteran Zombie Killer) ;)

AwesomeUser

23:40

Does EOL when

does EOL while scanning string literal mean anything to you

grovesNL

you are missing a single quote before features

Mat's Mug

EndOfLine?

AwesomeUser

Yes that fixed it. Thanks

nhgrif

Hmm. So, I know a bit about a few different languages... but I spend 40+ hrs a week writing mostly Objective-C (some C and some SQL). With that said, most of the time I'm able to see someone trying to do something they're used to in one language in Objective-C, and I can say "Wait--here's the Objective-C way to do that."

But now I've found something that's stumped me... abstract classes. Objective-C doesn't have abstract classes.

Mat's Mug

has interfaces?

nhgrif

23:44

An "interface", as I know it from Objective-C, is just a list of method and property declarations for the class.

Objective-C has protocols, which I think is like Java's interface.

rolfl

@Mat'sMug hey there

Mat's Mug

hey

rolfl

I think ... two things ... one, "What?", and two: you should consider putting together Blog:phase4

nhgrif

Who are you talking to?

Mat's Mug

what's phase 4?

nhgrif

23:46

Phase 1 was stealing underpants. And we're past phase 3, so obviously we have $$$$$ right?

rolfl

> meta.codereview.stackexchange.com/questions/1725/…

Mat's Mug

right, obviously. I thought "the next step" was in GraceNote's hands..

rolfl

also:

2 hours ago, by rolfl

Still, you posting the question here is a 'killcam' (come see what I did)

Just saying.

(EMP applied).

nhgrif

Anyway, an Abstract Class in Java could implement some of its methods, right? Like foo could be defined, and bar is only declared. A class inheriting the abstract class has to define bar, but wouldn't have to define foo, as it's already defined, right?

Mat's Mug

I sense unfair mod powers being used...

rolfl

23:48

Correct.

nhgrif

There's nothing like this in Objective-C.

rolfl

EMP - Evil Mod Power ;-)

Mat's Mug

ah!

rolfl

shhhhh

AwesomeUser

@grovesNL is there a way to take that data and analyze it in a variable instead of print it?

nhgrif

23:49

There is inheritance from what Java would consider a concrete class.

And there are "protcols" in Objective-C, which I think is what Java would call an "interface".

Mat's Mug

@nhgrif so.. is objective-c object-oriented? where's polymorphism?

Corbin

@AwesomeUser What have you tried? You should just be able to loop through it and assign a new value like blah["magType"] = blah["type"] and then just remove the type key. I'm not very familiar with Python though, so no idea on the specifics.

rolfl

As for the blog, I think we should prepare phase 4 anyway ..... (I have not heard anything from GraceNote... perhaps I should reach out.... but it has been busy in SE land recently, I don't want to push).

AwesomeUser

That makes sense. Thanks.

nhgrif

There's still polymorphism. You can have a single base class with several subclasses.

Mat's Mug

23:50

don't push (yet) - I think we should discuss what the first post ought to be about

nhgrif

In fact, nearly everything in Cocoa inherits from NSObject.

200_success

@AwesomeUser Try pretty-printing the JSON (with indentation) and you will probably figure it out.

rolfl

@nhgrif - Yes, Java has the interface, and, abstract classes, and classes.

nhgrif

And all the UI elements inherit from UIView.

rolfl

@Mat'sMug Which is why I think a phase4 post may be appropriate... but, not sure whether I should drive it, or not.....

nhgrif

23:51

And for example, UIView has an array of subviews. I can do something like
for (UIView *subview in myView.subviews) { subview.hidden = YES; }

Mat's Mug

@nhgrif I'd think that's describing inheritance... is there a way to "override" a given method from the base class, in the derived class?

nhgrif

You can override methods yes.

But you can't have abstract classes.

You can't have a class that declares a method without defining that method.

Mat's Mug

so it's like a beefed-up VB6 then! (kidding)

200_success

From what I understand, interfaces and abstract classes aren't a big deal in Objective C since duck typing works.

Mat's Mug

oh, well that changes quite a lot of things then!

rolfl

23:53

@Mat'sMug - in Phase 3, you are the only person (apart from a half-way-committed monkey), to offer to coordinate the blog. All the others are offers to write occasional items, and to review/edit posts.

nhgrif

At best, you could use preprocessor statements to prevent init from being called, declare your methods, and then just return nil in them all.

Mat's Mug

@rolfl so I'm the designated driver then?

nhgrif

The question is really more about how I tell someone who is coming from Java what to use in place of abstract classes

I'm an Objective-C programmer. I don't even think about Abstract classes.

The problem is more for how I help out someone who comes from a background like Java and want to continue using abstract classes.

rolfl

@Mat'sMug I am not sure... all I am saying, is that, if you want to drive it, then it is yours for the taking.

200_success

Nothing prevents you from writing abstract classes. You just aren't obligated to mark them as such.

Corbin

23:56

Hrmm, that's an interesting line of thought. I've never even slightly felt the need for abstract classes in ObjC. Seems like the correct response 99% of the time would be "if you think you need an abstract class, you're actually looking for a protocol"

I've never thought about going from Java to ObjC. That would be a rather jarring jump.

Mat's Mug

imagine C# to Objective-C. Jarring?

nhgrif

Hmm, if you're okay with compiler warnings, nothing prevents you from writing abstract classes, I guess.

Corbin

Yeah. That'd be pretty jarring too :/

Mat's Mug

M$ => iCode

nhgrif

And you do have to go out of your way to mark them as abstract actually... you have to prevent them from being created.

Otherwise they're not abstract in the Java sense of the word. You can't create an object of an abstract class type.

Corbin

23:58

ObjC feels a lot less rigid than Java, and I think that's a good example of it.

rolfl

@Mat'sMug I have a bad track record for keeping up the momentum on things like blogs.... (and new-year resolutions, and keeping journals, etc.). I can step up and help/facilitate as needed, and, if nudged and bumped along (carrot&stick type thing) then I can be useful.

Corbin

You could make an abstract class, but it'd be either by documentation or horrid hacks.

nhgrif

It wouldn't be that horrid.

Mat's Mug

@rolfl so, what, I just start writing? and post on meta?

nhgrif

- (id)init __unavailable__(("This class is abstract"));

Corbin

23:59

Yeah, I guess so. It wouldn't be nearly as clean as a built in language feature though.

nhgrif

And actually... I think that'd be problematic...

because as soon as you subclassed it and called self = [super init];...

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