Python multiprocessing.

Python multithreading. NOTE that although multiple threads can run within the python interpreter, ONLY one thread is being executed by the interpreter at any given time, which is ensured by the GIL (global interpreter lock) in python virtual machine. Python multithreading is more appropriate for I/O-bound applications than for CPU-bound applications as I/O releases GIL.

Java private field access.

Java okhttp client trustall certificate (for test only).

In Java, static fields and static methods are common but how about static class? Here is an example.

A working example on how to config postfix with gmail smtp server to send email directly from linux command line and tested on vagrant vm with ubuntu precise 32.

Java multithreading programming demo.

A javascript calendar.

How to pretty print json usually for better visibility.

Common regular expression symbols, characters, and usage.