J/J Just Joking

j/k just kidding

J2EE Java 2 Enterprise Edition

j2luk Just to let you know

J2ME Java 2 Micro edition
J2ME Java 2 Platform Micro Edition

J2SE Java 2 Standard Edition

J4I Just For Information

JAD Just Another day

JAO Just Another Observer

JAS Just A Second
JAS Just Another Story

JASE Just Another System Error

JAT Just A Thought

JAUA Just Another Useless Answer

JAWG Just A Wild Guess

JAWS Just Another Windows Shell

JBOD Just a Bunch of Disks

JBW Just Bloody Works

JC Just Curious

JCP Java Community Process

JD Jack Daniels
JD Job done

JDBC Java Database Connectivity

JDI Just do it

JDO Java Data Objects

JDOM Java Document Object Model

JDS Java Desktop System

JES Java Enterprise System

JFF Just For Fun

JFG Just For Grins

JFL Just for laughs

JFMAMJJASOND All the months of the year january february etc

JFTR Joint Federal Travel regulations

JFU Just For You

JFYI Just For Your Information

JIK Just in case

JIT Just In Time

JJA Just Joking Around

JK Just Kidding

JLD Just Like Dad

JLYK Just Letting You Know

JMHO Just my humble opinion

JMO Just My Opinion

JMOOC Just My Opinion Of Course

JMSNS Justification for Major System New Start

JMVHO Just my very humble opinion

JMWU Just Messing With You

JOOTT Just One Of Those Things

JPEG Joint Photographic Experts Group

JPW Just Plain Weird

JROTC Junior Reserve Officer Training Corps

JRPG Java Role Play Game

JSF Joint Strike Fighter

JSP Java Server Pages

JSYK Just So You Know

JT Just Teasing

JTAPI Java Telephony API

JTLYK Just to let you know

JTM Just Trust Me

JTUSK Just Thought You Should Know

JTYMLTK Just Thought You Might Like To Know

JTYWTK Just Thought you Wanted to Know

JTYWWTK Just Thought You Would Want To Know

JUAD Jumping up and down

JV Joint venture