Java : Formats are generally not synchronized.

From JavaDoc :

https://docs.oracle.com/javase/7/docs/api/java/text/Format.html

Formats are generally not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

 It allows for formatting (date -> text), parsing (text -> date), and normalization

Date formats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

Example : https://www.callicoder.com/java-simpledateformat-thread-safety-issues/

If using Java 8, it's better to use thread-safe

DateTimeFormatter

Git: merge ff vs --no-ff vs --ff-only

git merge --no-ff branch : force git à créer un commit avec un msg à garder dans l'historique
git merge --ff-only : force git à faire un merge uniquement s'il peut le faire avec un ff, sinon il doit abandonner.

liens:
http://www.dynamic-mess.com/developpement/git-merge-fast-forward-rebase-culture-git/
https://tech.m6web.fr/tentative-d-explication-des-fast-forward-sous-git

JavaScript : pass-by-reference or pass-by-value ?

 Data type manipulation in JavaScript

Type	Copied by	Passed by	Compared by
Number	Value	Value	Value
Boolean	Value	Value	Value
String	Immutable	Immutable	Value
Object	Reference	Reference	Reference

line : https://docstore.mik.ua/orelly/webprog/jscript/ch11_02.htm

Spatial locality and linkedlist

Spatial locality refers to the use of data elements within relatively close storage locations. Sequential locality, a special case of spatial locality, occurs when data elements are arranged and accessed linearly, such as, traversing the elements in a one-dimensional array.

Angular : Style Guide

https://angular.io/guide/styleguide

JavaScript :Test d’égalité

https://dorey.github.io/JavaScript-Equality-Table/
https://www.sitepoint.com/javascript-truthy-falsy/

Comparaison des objets par adresse et non pas par valeur, exemple :

var a = {a:1};
var b = {a:1};

isNaN != NaN

Nombres :

isNaN(NaN) => true
isNaN(undefined) => true => best practice = Number.isNaN(

https://stackoverflow.com/questions/25176459/is-number-isnan-more-broken-than-isnan

Self signed certificate in certificate chain (how to disable strict-ssl?)

set NODE_TLS_REJECT_UNAUTHORIZED=0