mttkay

public class Pager<I, O> {

    private static final Observable FINISH_SEQUENCE = Observable.never();

    private PublishSubject<Observable<I>> pages;
    private Observable<I> nextPage = finish();
    private Subscription subscription = Subscriptions.empty();

    private final PagingFunction<I> pagingFunction;
    private final Func1<I, O> pageTransformer;

leonardofed

A curated list of AWS resources to prepare for the AWS Certifications

A curated list of awesome AWS resources you need to prepare for the all 5 AWS Certifications. This gist will include: open source repos, blogs & blogposts, ebooks, PDF, whitepapers, video courses, free lecture, slides, sample test and many other resources.

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jdegoes

Applied Functional Programming with Scala - Notes

Copyright © 2016-2018 Fantasyland Institute of Learning. All rights reserved.

1. Mastering Functions

A function is a mapping from one set, called a domain, to another set, called the codomain. A function associates every element in the domain with exactly one element in the codomain. In Scala, both domain and codomain are types.

val square : Int => Int = x => x * x

tuxpower

List AWS regions and parsing using jq:

$ aws ec2 describe-regions | jq '.Regions[].RegionName'

"ap-south-1"
"eu-west-1"
"ap-southeast-1"
"ap-southeast-2"
"eu-central-1"
"ap-northeast-2"

wojteklu

Code is clean if it can be understood easily – by everyone on the team. Clean code can be read and enhanced by a developer other than its original author. With understandability comes readability, changeability, extensibility and maintainability.

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General rules

1. Follow standard conventions.
2. Keep it simple stupid. Simpler is always better. Reduce complexity as much as possible.
3. Boy scout rule. Leave the campground cleaner than you found it.
4. Always find root cause. Always look for the root cause of a problem.

Design rules

BenderV

Just do something, doesn't matters what 
Book == blog archives. Feel free to scram
We are creatures of habits (but don't condition habits with identity/ego). Have deliberate habits 
Stopping alcohol 
Unpack causes 
- availability
- desire 

Availability => Early morning sport. Force to not go out at night too much. 
Desire 

danielflower

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.nio.file.*;

public class FileWatcher {
	private static final Logger log = LoggerFactory.getLogger(FileWatcher.class);

	private Thread thread;

djspiewak

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

RajenDharmendra

1、select avg(ss_item_sk) from store_sales;
2、select ss_sold_Date_sk,count(*) as cnt from store_sales group by ss_sold_Date_sk order by cnt desc,ss_sold_Date_sk limit 10;
3、select ss_sold_Date_sk,avg(ss_item_sk) as cnt from store_sales group by ss_sold_Date_sk order by cnt desc,ss_sold_Date_sk limit 10;
4、select ss_item_sk,count(*) from store_sales group by ss_item_sk having count(*)>1 limit 10;
5、select sum(ss_item_sk) from store_sales;
6、select ss_sold_Date_sk,ss_wholesale_cost,avg(ss_item_sk) as cnt from store_sales group by ss_sold_Date_sk,ss_wholesale_cost order by cnt desc,ss_sold_Date_sk limit 10;
7、select ss_sold_Date_sk,ss_wholesale_cost,avg(ss_item_sk) as cnt from store_sales group by ss_sold_Date_sk,ss_wholesale_cost  order by cnt desc,ss_sold_Date_sk limit 10;

8、select ss_sold_Date_sk,ss_wholesale_cost,avg(ss_item_sk) as cnt,count(distinct(ss_sales_price)) as avg1 from store_sales group by ss_sold_Date_sk,ss_wholesale_cost  order by cnt desc,ss_sold_Date_sk limit 10;

amaembo

import java.util.*;

@SuppressWarnings("ALL")
class Test {
  static class ReifiedList<T> extends AbstractList<T> {
    private final List<T> delegate = new ArrayList<>();
    private final Class<?> type;

    @SafeVarargs
    ReifiedList(@Deprecated T... unused) {