This build tries to balance HP,AR and MR for maximum efficiency when it come to taking damage.
it also gives AD in early game allowing for early kills and thus faster levelling and gold.
this build not only focusses on survivability (balancing HP/AR/MR) but also on AD/AS/armor penetration/Slowing NMEs and making optimal use of abilities with the help of proper items, runes and masteries for penetrating armor, attack damage and attack speed, which are the essential factors for Jarvan. The build you use depends on the role you play in-game, therefore I have made additional builds for different situations.

Abbreviations:
Q Dragon Strike
W Golden Aegis
E Demacian Standard
R Cataclysm

AR=armor
AD=attack damage
AS=attack speed
ArP=armor penetration
MR=magical resistance
CD=cooldown

Attack speed:
Increase you attack speed by over 10% from the start of a match.

Armor Penetration:
Armor penetration is a must; this build focusses on AP as well (+10 ArP from start).

Armor
Double your survivability in early game (from 17 to 36 armor from start)

The advantages these runes give in early game allow you to get easier early kills and thus level faster and gain more gold!

Most skill points are given to offence (22/6/3).
This due to increased attack speed, attack damage and armor penetration (the focus of jarvan)
next to that, point in armor and magical resistance + health and mana regeneration (to improve Jarvan's survivability).

Fighting style: Aggressive
I would recomment this if you know how to handle jarvan and its my personal favorite.
I usually use the build that focuses more on AD: see 'you are in a team with tanks' in the next section, and thus replace Frozen mallet with either another tiamat or Last whisper.
also buy tiamat right after Youmuu's ghostblade, before you buy Warden's Mail.

level 18 stats when using teh aggresive build:

Health
Hit Points 2340 (+300)
Health Regen (per 1) 28 (+8)
Health Regen (per 5) 140 (+40)
Physical Damage Health 6855.96 (+2898.37)
Magical Damage Health 3580.19 (+459)
Effective Health 5218.08 (+1678.68)
Mana
Mana 775 (+0)
Mana Regen (per 1) 15 (+1)
Mana Regen (per 5) 75 (+5)
Damage
Attack Speed 1.124 (+0.463)
Damage 286 (+175)
Ability Power 0 (+0)
Armor Penetration 30 (+30)
Armor Penetration (%) 40% (+40)
Magic Penetration 0 (+0)
Magic Penetration (%) 0% (+0)
Critical Chance 15% (+15)
Critical Damage 200% (+0)
Resistances
Armor 192.9898 (+98.99)
Magic Resist 52.9997 (+0)
Dodge 0% (+0)
Bonuses
Lifesteal 0% (+0)
Spell Vampirism 0% (+0)
Mana Burn 0 (+0)
Cooldown Reduction 20% (+20)
General
Range 175 (+0)
Movement Speed 385 (+70)

Fighting style: Defensive/Supportive
Use the build that gives you balanced HP/AR/AP.
See: 'you are in a team without tanks' in the next section.
This is also a good build to train with jarvan if ur not experienced with this champ
or when your gaol is to tank and push.

Level 18 stats when using the defensive build:

Health
Hit Points 3040 (+1000)
Health Regen (per 1) 33 (+13)
Health Regen (per 5) 165 (+65)
Physical Damage Health 8906.89 (+4949.29)
Magical Damage Health 6961.59 (+3840.4)
Effective Health 7934.24 (+4394.85)
Mana
Mana 775 (+0)
Mana Regen (per 1) 14 (+0)
Mana Regen (per 5) 70 (+0)
Damage
Attack Speed 1.124 (+0.463)
Damage 216 (+105)
Ability Power 0 (+0)
Armor Penetration 30 (+30)
Armor Penetration (%) 0% (+0)
Magic Penetration 0 (+0)
Magic Penetration (%) 0% (+0)
Critical Chance 15% (+15)
Critical Damage 200% (+0)
Resistances
Armor 192.9898 (+98.99)
Magic Resist 128.9997 (+76)
Dodge 0% (+0)
Bonuses
Lifesteal 0% (+0)
Spell Vampirism 0% (+0)
Mana Burn 0 (+0)
Cooldown Reduction 20% (+20)
General
Range 175 (+0)
Movement Speed 415 (+100)


Fighting style: Hybrid
This is the original build shown in the purchase order section above.
The build focuses on AR, AD, AS, ArP and slows.
The build does not include magic resistance like the 'defensive build',
however it gives more AD.

Level 18 stats when using the hybrid build:

Health
Hit Points 3040 (+1000)
Health Regen (per 1) 28 (+8)
Health Regen (per 5) 140 (+40)
Physical Damage Health 8906.89 (+4949.29)
Magical Damage Health 4651.19 (+1530)
Effective Health 6779.04 (+3239.65)
Mana 775 (+0)
Mana Regen (per 1) 15 (+1)
Mana Regen (per 5) 75 (+5)
Damage
Attack Speed 1.124 (+0.463)
Damage 266 (+155)
Ability Power 0 (+0)
Armor Penetration 30 (+30)
Armor Penetration (%) 0% (+0)
Magic Penetration 0 (+0)
Magic Penetration (%) 0% (+0)
Critical Chance 15% (+15)
Critical Damage 200% (+0)
Resistances
Armor 192.9898 (+98.99)
Magic Resist 52.9997 (+0)
Dodge 0% (+0)
Bonuses
Lifesteal 0% (+0)
Spell Vampirism 0% (+0)
Mana Burn 0 (+0)
Cooldown Reduction 20% (+20)
General
Range 175 (+0)
Movement Speed 385 (+70)

You start off with a pendant and 1 health potion in order to stay in your lane as long as possible. DO NOT return to base before you're lvl 8-10 (you don't want to slow your XP and gold earnings). Afterwards, buy the vest to give you some decent protection early game, along with the boots (movement 1). The brutalizer is a must before finishing the recipe with Youmuu's ghostblade (giving you damage/ArP/Speed/CD reduction/Crit chance/AS and movement speed). You now deal some decent damage in early game. After finshing ghostblade you can do several things depending on your style; like going for taimat which gives 50 extra dmg and gives 30%-50% extra AoE damage to nearby enemies, especially usefull when getting rid of minions. It also increaases both HP and mana regen. You can go for Warden's mail instead before purchasing the taimat, giving extra armor and HP regen (for little money). Afterwards, you want the frozen mallet for HP increase and some extra damage + slowing enemies which is a great addition. The last spot is filled with teh black cleaver for nice damage output + armor reduction after physical hits (nice combination with Armor penetration items; specially if your going for a more aggressive build and buy Last whiper instead of Frozen mallet). Last but not least, you can upgrade Warden's mail to randuin's omen for some extra armor.

situation 1: You are facing massive magical damage:
Instead of chain vest, go for negatron cloak.
Lose warden's mail and buy Force of nature instead.

situation 2: You are facing massive physical damage:
Use current build but upgrade wardens mail to randuin's omen
before purchasing the Tiamat.

situation 3: You are in a team with tanks (Aggresive Build):
Keep Warden's Mail: You want HP regen + extra armor for a small price.
After youmuu's ghostblade, go straight for tiamat and warden's mail afterwards.
Lose frozen mallet and go for last whisper instead (thus, leave HP, take AP).
Instead of last whisper,another tiamat is a cheap alternative.
(infinity edge is better but much more expensive)
last change: upgrade warden's mail to randuin's omen

sitution 4: You are in a team without tanks (Defensive Build):
Use current build, good survivability and damage, BUT:
Lose tiamat and go straight for wardens mail (since you need the spot for Force of Nature)
If your facing massive physical damage: follow situation 2.
if your facing massive magical damage: follow situation 1.
Buy force of nature right after wardens mail. (still having a hard time?:
upgrade warden to randuins omen). This gives massive survivability since HP/AR/MR are balanced. Afterwards, go for the frozen mallet and finally The black cleaver.

situation 5: You are facing a balanced team and are in a balanced team:
use original build shown in the purchasing order.

You should start of with Q. It is perfect to her*** opponents. After that, E is your priority, since you want to use its attack speed. keep leveling up Q when E cannot. Unlock W at level 4; keep it at level 1 untill the end (then u atleast make use of its slow and extra HP ability to get out of fights). As soon as your ulti is ready, unlock it.

Importance:
E>Q>R>W
E for speed
Q for her***ment
R for stopping opponents
W for slowing opponents down + protection when being chased


Additional Skills:
Go for Clarity for mana and Ignite/exhaust or flash depending on your play style.
I prefer Ignite as a finising touch for the kill. Flash is good to escape your cataclism.

Play SOLO
make sure you're laning and farming as much as possible.
don get killed and stay back by her***ing with Q and throwin E on top
(dont use the stuble QE combo unless ur on high HP and the other is not)
have to stay near minnions.
you might have a tough time vs. Ranged like ezreal, but the build is
designed to give early AD; after a few lvls you can start feeding yourself
do NOT use abilities on minions in early game.

Play 2v2
keep ur distance while her***ing opponents with Q.
do NOT use abilities on minion in early game.
if theres backup, try placing E behind opponents and stuble them.
autoattack when theyre down>use R if they're trying to run and/or ignore/exhaust
if you are being ganked, try fleeing with the same QE combo.
or use R to lock NMEs, and subsequently drag urself out with either QE combo or flash.


Play 5v5
dont consider urself a vast tank, despite the fact that u have some survivability with this build.
ur not a tank, let ur tank make the first move; wait for an opening, then hit R and use EQW combo.
also use ignite to speed things up> if ur dying swing out with the QE combo or use flash.

you do not have a tank at ur disposal?>her*** with Q and E (dont use the combo),wait for opponents
to make a move and hit R accordingly. Once inside, use ignite to speed it up or flash to get out if ur dying.

Concluding remarks
remember>dont initiate the battle too fast, but keep a safe distance and wait for the opening.
jarvan is a graet killer that can take many hits, its still does less AD than irelie etc and can take less than tankers like mundo.

Farming is very important for Jarvan; the pendant and health potion should allow you to remain in the lane untill you can atleast buy the regular boots, a chain vest and the brutalizer.
Going back to recooperate only takes time! Play defensive at the start.

First: Clarity (increase mana)
This is a must for jarvan, since his mana pool drains fast.
With this spell, you can focus on some HP regen and armor at the very start,
and not waste your money on mana potions or regen.

Second: Ignite (OR: Flash)
I personally prefer ignite, since it often lends the finishing blow to enemies in early game.
So you can get kills faster in early game, and thus lvl faster andd gain more gold than ur opponent. You can also use flahs, since it is handy to get out of your cataclysm/simple run or gain up on an NME for the finishing blow. Exhaust is also useful; however, I prefer early game kills for fast xp/gold. Hence, use Ignite.

with the runes and items u are able to get high armor penetration.
with the defensive build, you are a great tank by balancing Health points and mitigation while still deal good damage early in game.
With the aggresive build, you deal great damage with decent (but enough)survivability; this may require more exp with jarvan (timing and finding openings for a kill).
I recommend starting off with the defensive build get the hang of Jarvan, subsequently move to hybrid and aggressive respectively.