J. Kevin Robbins

That does help a bit, yes. I am working with a modal which doesn't use routing. A click on a navbar menu runs the open() method of the modal and then the submit or cancel buttons close it so there is no routerLink. But it sounds like the modal is a child of the navbar and a grandchild of the main page.

I finally sorted out the Observer/Subscriber problem I was having but this clears things up a bit for future challenges.

Thanks

I'm studying data sharing and binding and every article refers to parent and child components or sibling components, but I can't find anything that explains this relationship. How do I know if a component is a parent or a child and to whom? Or determine two siblings?

One article made a brief mention of showing the nesting in the app.component.html file, but not all components are listed in this file so that's no help.

Specifically I have a bootstrap modal component that is standalone. It updates information that must be displayed on a landing page.

Thanks for all the info. It may not fit this project but it's a good tool to have in your toolbox.

I've never heard of ETL. It looks interesting but I doubt I have time to get it approved and working. Never time to do it right, but always time to do it over, eh?

Hi Campbell. That is a very interesting solution that didn't even occur to me. I'm going to have to look into that a little deeper today.

Hi Rob.

That's where I sort of ended up by the end of the day yesterday, except I opted for StringBuffer since it's synchronized and this gateway will see lots of traffic. Does that make sense or would it be better to use StringBuilder and synch it myself? Or am I just assuming the need for synchronization?

My Java is rusty or I wouldn't have spent the last hour looking for a solution to this. I'm working on a gateway/adapter from a Java server to a mainframe. Each request must begin with a 307 character header (called ESSH). Other data will be added after the header, but that's a problem for later. The string will look sort of like this:

"C            20190501API_CODE_HERE        X          SOURCE   999        BLAH       XXXXX X       " etc on out to exactly 307 characters regardless of spaces.

The class I'm creating will have a bunch of setters that must place the data at a specific starting position and with a certain length.

I've played around with a fixed length array, an ArrayList, and a StringBuilder but I'm having challenges with each of them. I'm beginning to think that I need to split each string into characters and put them into a character array. But this seems to be getting over-complicated.

I saw one solution that uses MarshallStringUtils to stuff everything into a byte array but that make my head hurt just looking at it.

I'd love to hear ideas on how others would approach this problem. Thanks.

I think the light bulb just came on. When you said iterate it clicked.

this.servers is a collection of JavaScript objects of server information. Sort of like an List of Objects in Java terms. "Find" iterates through that list (like a for loop) and (s) holds a single server record as Find iterates through the collection, hence it can be used for comparison in the equality test in the first return statement. I couldn't see where (s) was getting initialized with a value because I didn't equate find to a for loop.

It all makes sense now. I don't know why I didn't see it. Thank you!

Thanks, good to be back.

It helps to see that in a format that I'm familiar with. One thing I found confusing is the "(s)". I thought the item or items in parenthesis just before the => were parameters to the inner function. But in this case is doesn't look like a parameter but rather a variable that will receive the value of the first return. But that doesn't make sense because the "const server" is where the final result ends up. If it's a parameter, what's it's value? Confusing.

As for streams, I actually haven't done much Java, almost no version 8, in the last couple of years. Some Java 5 (yes, really) lots of SQL, some PHP (ugh), some AWS cloud stuff (that was fun) and then I got tossed into the deep end of the Angular pool where I seem to do more sinking that swimming. Routing has me pulling out what little hair I have left. I know lambdas will sink in eventually but it's still frustrating at this point. I find them very difficult to read.

I miss JSP's and jQuery. That I understood. But that's obsolete tech now. I've been job hunting since November and saw very, very few jobs looking for JSP. I start my new job on Monday as an Angular developer so I've been bingeing on it for over a month. All those tutorials are exhausting.

I'm really beginning to hate fat arrow functions. Can someone re-write this so the inner function is a regular, private function called from the outer function? No anonymous inner stuff, just split this into two functions so maybe I can begin to understand how it works.

Thank you.

getServer(id: number) {    const server = this.servers.find(      (s) => {        return s.id === id;      }    );    return server;  }

After this I've got one with nested functions. That will be fun. This stuff is giving me a headache.  

I'm fire hose training on Angular and bootstrap and there are some things that I'm having trouble getting my head wrapped around. Specifically, the @Input and @Output decorators and Observables and EventEmitters. I know, input and output are basic level stuff, but I still find myself following tutorials and asking "how did he decide that @Input had to go there?" There seems to be some basic concept that I just haven't grasped yet.

So, I'm looking for suggestions on books, websites, or tutorials (I'll pay for good ones). Some resource that did a good job of covering these topics, something that made the light bulb go on for you.

All suggestions are appreciated!

And the rabbit hole just gets deeper.  

Thank you. I actually understand that explanation. I wish I had learned calculus. It seems fascinating. I recall seeing that scene in "The Day the Earth Stood Still" where Keanu Reeves and John Cleese are scribbling equations on the board as if they are having a conversation in numbers. Is that really possible?

Interesting conversation. I would have answered no, it's not a programming language because it has no logic branching abilities such as if-then. It's just a text markup language.

But on the other hand it is a way of telling the computer (or browser) what to do, so I can see the argument that it should be considered a programming language.

It's a gray area. I think we would have to first step back and define "what is a programming language". Otherwise we're just arguing semantics.

Campbell Ritchie wrote:
∀e • e ∈ Exceptions ⇒ ¬canThrow(superclassMethod, e) ⇒ ¬canThrow(subclassMethod, e)
Remember that ⇒ associates to the right, and you can use the contrapositive rule to turn the right part of that implication round:-
p ⇒ q ≡ ¬q ⇒ ¬p
∴ ¬canThrow(superclassMethod, e) ⇒ ¬canThrow(subclassMethod, e) ≡
canThrow(subclassMethod, e) ⇒ canThrow(superclassMethod, e)

Damn math majors. You just made my head explode before my first cup of coffee. I'm going to reveal my lack of education here and admit that I've never even seen this kind of notation. Can you explain what I'm looking at here? Would I need to take 3 years of calculus to understand it?