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.

---

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

jboner

Latency Comparison Numbers (~2012)
----------------------------------
L1 cache reference                           0.5 ns
Branch mispredict                            5   ns
L2 cache reference                           7   ns                      14x L1 cache
Mutex lock/unlock                           25   ns
Main memory reference                      100   ns                      20x L2 cache, 200x L1 cache
Compress 1K bytes with Zippy             3,000   ns        3 us
Send 1K bytes over 1 Gbps network       10,000   ns       10 us
Read 4K randomly from SSD*             150,000   ns      150 us          ~1GB/sec SSD

sualeh

How to Sign and Release to The Central Repository with GitHub Actions

GitHub allows automated builds using GitHub Actions. A commonly asked question is how to release artifacts (packaged Java jars) built by Maven and Gradle to The Central Repository. The GitHub Actions documentation provides only part of the answer.

So, first, configure your Maven project for staging artifacts to The Central Repository, by reading through Configuring Your Project for Deployment and following those steps. Please make sure that the maven-gpg-plugin is configured to prevent gpg from using PIN entry programs, as follows:

<configuration>
  <gpgArguments>
      <arg>--pinentry-mode</arg>
 loopback

gavinandresen

# Raw transaction API example work-through
# Send coins to a 2-of-3 multisig, then spend them.
#
# For this example, I'm using these three keypairs (public/private)
# 0491bba2510912a5bd37da1fb5b1673010e43d2c6d812c514e91bfa9f2eb129e1c183329db55bd868e209aac2fbc02cb33d98fe74bf23f0c235d6126b1d8334f86 / 5JaTXbAUmfPYZFRwrYaALK48fN6sFJp4rHqq2QSXs8ucfpE4yQU
# 04865c40293a680cb9c020e7b1e106d8c1916d3cef99aa431a56d253e69256dac09ef122b1a986818a7cb624532f062c1d1f8722084861c5c3291ccffef4ec6874 / 5Jb7fCeh1Wtm4yBBg3q3XbT6B525i17kVhy3vMC9AqfR6FH2qGk
# 048d2455d2403e08708fc1f556002f1b6cd83f992d085097f9974ab08a28838f07896fbab08f39495e15fa6fad6edbfb1e754e35fa1c7844c41f322a1863d46213 / 5JFjmGo5Fww9p8gvx48qBYDJNAzR9pmH5S389axMtDyPT8ddqmw

# First: combine the three keys into a multisig address:
./bitcoind createmultisig 2 '["0491bba2510912a5bd37da1fb5b1673010e43d2c6d812c514e91bfa9f2eb129e1c183329db55bd868e209aac2fbc02cb33d98fe74bf23f0c235d6126b1d8334f86","04865c40293a680cb9c020e7b1e106d8c1916d3cef99aa431a56d253e69256dac09ef122b1a9

kdabir

def m = "1234 abc" =~ /^(\d+)/
def n = "abc 1234" =~ /^(\d+)/

println (m.find()?m.group():"not matched")
println (n.find()?n.group():"not matched")

chrismdp

# You don't need Fog in Ruby or some other library to upload to S3 -- shell works perfectly fine
# This is how I upload my new Sol Trader builds (http://soltrader.net)
# Based on a modified script from here: http://tmont.com/blargh/2014/1/uploading-to-s3-in-bash

S3KEY="my aws key"
S3SECRET="my aws secret" # pass these in

function putS3
{
  path=$1

lemiorhan

How to make a release with Git and Maven via JGitFlow

Imagine that you are versioning your sourcecode in git and building your code via maven. You need to make releases before deploying to production regularly. What should be the strategy we need to follow for releasing?

I've used maven-release-plugin for years to make releases. It worked perfectly with maven and svn, but we started to face problems when we migrated our code to git and to make releases on git.

After checking the literature, we decided to use JGit-Flow which is a maven plugin based on and is a replacement for the maven-release-plugin enabling support for git-flow style releases via maven.

I do not want to explain the details much because there are many great posts explaining all.

subfuzion

Reference: RFC 2616 - HTTP Status Code Definitions

• HTTP/1.1 Status Code Definitions
• Additional HTTP Status Codes

General

• 400 BAD REQUEST: The request was invalid or cannot be otherwise served. An accompanying error message will explain further. For security reasons, requests without authentication are considered invalid and will yield this response.
• 401 UNAUTHORIZED: The authentication credentials are missing, or if supplied are not valid or not sufficient to access the resource.
• 403 FORBIDDEN: The request has been refused. See the accompanying message for the specific reason (most likely for exceeding rate limit).
• 404 NOT FOUND: The URI requested is invalid or the resource requested does not exists.
• 406 NOT ACCEPTABLE: The request specified an invalid format.

porjo

Convert sequence of JPEG images to MP4 video

Simple glob:

ffmpeg -r 24 -i '*.JPG' -s hd1080 -vcodec libx264 timelapse.mp4

Start from DSC_0079.JPG

ffmpeg -r 24 -f image2 -start_number 79 -i DSC_%04d.JPG -s hd1080 -vcodec libx264 timelapse2.mp4

jewelsea

import java.sql.*;
import java.util.logging.*;
import javafx.application.Application;
import javafx.collections.*;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.stage.Stage;