Don't feed the enemy, it is bad.

This is the way that i handle Jarvan IV.
Jarvan is one of my favourite tanks. He has great iniciating skills, lane sustainability, a lot of damage output (especially earlt game) and he is great for chasing enemies or running away from them.

I take armor penetration for obvious reasons.
Dodge seals - the thing is that i usually play Jarvan when the enemy team has a lot of attack speed characters such as Kog Maw, Caitlyn, Warwick and Master Yi. Dodge seals and Ninja Tabi will help you dodge most of the enemie's attacks which could be critical strikes and that is very crucial.
Mana regeneration is not really a recommended Glyph, instead you can take armor, magic resistance, health and even cooldown reduction even though you dont really need it.
Armor pen quints for obvious reasons.

Defensive masteries will help you have more lane sustainability and be able to take enough punishment from physical attacks. Nimbleness is needed to give you a speed boost while running away from enemies or chasing them. I usually take teleport and flash.
Teleport can help you get into teamfights and go back to your lane quicker and flash will help you iniciate/run/chase.

The item build is a pretty old one, but still my favourite. Tanky DPS Jarvan is in my opinion the best.
When you have enough gold go back to base to buy your Philosopher's Stone and Heart of Gold. This way if you get killed about 5 mins later, you won't be falling behind in gold. Frozen mallet is just awesome. Warmog's is just awesome. Atma's is just awesome. Last whisper is just awesome. Banshee's veil can be changed with a force of nature if you want to be tankier, anyways these both items are just awesome

Pros :
1. Great iniciator
2. Easy to master
3. Incredibly fun to play
4. He can deal TONS of damage
5. Makes most enemies claustrophobic

Cons :
1. Sometimes you get claustrophobic yourself
2. Doesn't always deal TONS of damage
3. Not really all that fun to play
4. Not so easy to master.
5. Doesn't always iniciate so well

Play Video This guide is much more detailed and easier to understand than mine.
*Lalalalala Demaciaaaaa*