bradtraversy

SSH Cheat Sheet

This sheet goes along with this SSH YouTube tutorial

Login via SSH with password (LOCAL SERVER)

$ ssh brad@192.168.1.29

Create folder, file, install Apache (Just messing around)

$ mkdir test

$ cd test

Yogendra0Sharma

# Redis Cheatsheet
# All the commands you need to know


redis-server /path/redis.conf  # start redis with the related configuration file
redis-cli                      # opens a redis prompt


# Strings.

iSergius

Below are the Big O performance of common functions of different Java Collections.


List                 | Add  | Remove | Get  | Contains | Next | Data Structure
---------------------|------|--------|------|----------|------|---------------
ArrayList            | O(1) |  O(n)  | O(1) |   O(n)   | O(1) | Array
LinkedList           | O(1) |  O(1)  | O(n) |   O(n)   | O(1) | Linked List
CopyOnWriteArrayList | O(n) |  O(n)  | O(1) |   O(n)   | O(1) | Array

imax

Compare cost of living in different locations around the world.

Country (city)	Salary (gross)	Taxes	Apartment	Visa	More info
Germany (Berlin)	€50-60k	27-33%	€700-1200/mo	Blue Card, 1-3 months, spouse can work	de_faq на русском Numbeo
Estonia (Tallinn)	€35-45k	41.5%	€600-1200/mo	2 months, spouse can work	Taxes
xxx

Legend:

Firefishy

#!/bin/bash
set -e

JAVA_HOME=${1-text}
[ $# -eq 0 ] && { echo "Usage: sudo $0 \$(/usr/libexec/java_home -v '1.8*')" ; exit 1; }

KEYSTORE=$JAVA_HOME/jre/lib/security/cacerts

wget https://letsencrypt.org/certs/letsencryptauthorityx1.der
wget https://letsencrypt.org/certs/letsencryptauthorityx2.der

vasanthk

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

xkr47

# input: fullchain.pem and privkey.pem as generated by the "letsencrypt-auto" script when run with
# the "auth" aka "certonly" subcommand

# convert certificate chain + private key to the PKCS#12 file format
openssl pkcs12 -export -out keystore.pkcs12 -in fullchain.pem -inkey privkey.pem

# convert PKCS#12 file into Java keystore format
keytool -importkeystore -srckeystore keystore.pkcs12 -srcstoretype PKCS12 -destkeystore keystore.jks

# don't need the PKCS#12 file anymore

lolzballs

import java.io.FileDescriptor;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;

public class HelloWorld{
	private static HelloWorld instance;
    public static void main(String[] args){
        instantiateHelloWorldMainClassAndRun();

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

thomseddon

/**
 * The MIT License (MIT)
 *
 * Copyright (c) 2013 Thom Seddon
 * Copyright (c) 2010 Google
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell