Elifarley C. elifarley

#Intro

Kotlin is a new programming language for the JVM. It produces Java bytecode, supports Android and generates JavaScript. The latest version of the language is Kotlin M5.3

Kotlin project website is at kotlin.jetbrains.org.

All the codes here can be copied and run on Kotlin online editor.

Let's get started.

Java to Dart

This is an ad-hoc Java-to-Dart translator originally written on two (admittedly long) evenings.

See http://sma.github.io/stuff/java2dartweb/java2dartweb.html for a demo.

Note: It doesn't support the complete Java grammar specification and cannot translate everything. It only translates syntax and does not attempt to translate Java library classes and methods to Dart equivalents (with the exception of String.charAt and StringBuffer.append). You will have to make changes to the resulting Dart code. It does not support anonymous inner classes.

However, I was able to successfully convert a 7000+ line command line application with only minimal fixes in 30 minutes.

	-- PostgreSQL cheat sheet

	--postgres is set up to use local.6 which is syslog'd to sflog001
	--slow query log is /var/log/localmessages
	--config files are always in /data/friend/*.conf

	--vacuums are set via cfengine, we use both manual and auto. vacuums/analyze help with frozen id's being recouped, and thus TX'id's not going over 2b thus causing massing shutdown/reset. Fix it to exp/imp high TX tables.

	--to log into psql: psql -U postgres -d <DB> (usually friend)

	# GNU Screen - main configuration file
	# All other .screenrc files will source this file to inherit settings.
	# Author: Christian Wills - [email protected]

	# Allow bold colors - necessary for some reason
	attrcolor b ".I"

	# Tell screen how to set colors. AB = background, AF=foreground
	termcapinfo xterm 'Co#256:AB=\E[48;5;%dm:AF=\E[38;5;%dm'

	using System;
	using System.Diagnostics.Contracts;
	using System.Linq;

	namespace Merkator.Tools
	{
	public class ArrayHelpers
	{
	public static T[] ConcatArrays<T>(params T[][] arrays)
	{

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
	FROM pg_stat_activity
	WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
	ORDER BY query_start desc;

	-- show running queries (9.2)
	SELECT pid, age(clock_timestamp(), query_start), usename, query
	FROM pg_stat_activity
	WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'

	// UTF8 Module
	//
	// Cleaner and modularized utf-8 encoding and decoding library for javascript.
	//
	// copyright: MIT
	// author: Nijiko Yonskai, @nijikokun, [email protected]
	(function (name, definition, context, dependencies) {
	if (typeof context['module'] !== 'undefined' && context['module']['exports']) { if (dependencies && context['require']) { for (var i = 0; i < dependencies.length; i++) context[dependencies[i]] = context['require'](dependencies[i]); } context['module']['exports'] = definition.apply(context); }
	else if (typeof context['define'] !== 'undefined' && context['define'] === 'function' && context['define']['amd']) { define(name, (dependencies \|\| []), definition); }
	else { context[name] = definition.apply(context); }

	Byobu Commands
	==============

	byobu Screen manager


	Level 0 Commands (Quick Start)
	------------------------------

	<F2> Create a new window

	object FlickrBase58Coder {
	val alpha = "123456789abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ"
	val base = alpha.length

	def apply(encodedInput: String) = decode(encodedInput)
	def apply(decodedInput: Long) = encode(decodedInput)

	def encode(input: String): String = encode(input.toLong)
	def encode(input: Long) = {
	def enc(in: Long, acc: String): String = if (in < 1) acc else enc(in / base, alpha((in % base).toInt) + acc)

	function retry(isDone, next) {
	var current_trial = 0, max_retry = 50, interval = 10, is_timeout = false;
	var id = window.setInterval(
	function() {
	if (isDone()) {
	window.clearInterval(id);
	next(is_timeout);
	}
	if (current_trial++ > max_retry) {
	window.clearInterval(id);