[1.8]Storing custom nbttags on player or entityes Little question. inventories

i have this little issue whith this of writing custom nbttag to entityes

i been working if a wololo staff there is a later post, but

i store the ownweUUID as string in an nbt whith the same name is done in entityTameable

for that i du

			UUID uuid = playerIn.getUniqueID();
			String Suuid = playerIn.getUniqueID().toString();

			NBTTagCompound targetNBT = target.getEntityData();
			targetNBT.setString("OwnerUUID", Suuid); //

this write the uuid to targetEntity i can later reade it.

if i close completely minecraft restart the pc fireup again the minecraft

the nbt is still there but is only accessible in the server side coz in the client side it allways return empty,

and i notice there is not an

target.setEntityData(NBTTagCompound targetNBT);

############################

i think is becoze i been mising something to writte the nbttag whith the change again to entity

soo nbttags gets magicaly update or what is the code to write an nbttag to an entity ??

i ask this coz today im working in a complex entitie that gona manage a complex firegun, well i gone try to fix the mark2lacer from mi mod

this entity has to have access to the player Inventory but like i wana do this gun compatible whith mi custom mobs the methods to check if the entity has magazines or bullets must be compatibles whith EntityLivingBase plus must be able to read from the inventories i be done in custome armour,  that means i have to extract the inventory rigth from the nbtags rater than the playerIn.inventory.methods and later writing back when comsume bullets or magazines 

something like

// #########################################################################3
// @Override
public void readFromNBT() {
this.clear(); //delete the contens from the inventory arrays

//here is to inventoryes array []
// shootinginventario[] for the player or mob inventory  and
// inventario[]  for the items store in the armour pockets 
//later i gona join this two in only one to make easy  

	// Shoting Entity Inventory
	if (shootingEntity != null) {

		NBTTagCompound compound3 = shootingEntity.getEntityData();

		if (compound3 != null) {

			NBTTagList nbttaglist3 = compound3.getTagList("Items", 10);

			if (nbttaglist3.tagCount() > 0) {

				for (int i = 0; i < nbttaglist3.tagCount(); ++i) {

					NBTTagCompound nbttagcompound3 = nbttaglist3.getCompoundTagAt(i);
					int j = nbttagcompound3.getByte("Slot") & 255;

					if (j >= 0 && j < shootinginventario.length) {
						shootinginventario[j] = ItemStack.loadItemStackFromNBT(nbttagcompound3);

						if (shootinginventario[j] != null) {
						}

					}
				}

			}

		}

	}

	inventario[0] = this.shootingEntity.getEquipmentInSlot(0);// .getHeldItem();
	inventario[3] = this.shootingEntity.getEquipmentInSlot(3);// getCurrentArmor(2);chest

	chestItem = inventario[3]; // this.entidad.getEquipmentInSlot(3);


	//inventario en la armadura
	if (chestItem != null) {

		NBTTagCompound compound2 = chestItem.getTagCompound();

		if (compound2 != null) {

			NBTTagList nbttaglist2 = compound2.getTagList("Items", 10);

			if (nbttaglist2.tagCount() > 0) {

				for (int i = 0; i < nbttaglist2.tagCount(); ++i) {

					NBTTagCompound nbttagcompound1 = nbttaglist2.getCompoundTagAt(i);
					int j = nbttagcompound1.getByte("Slot") & 255;

					if (j >= 0 && j < inventario.length) {
						inventario[j] = ItemStack.loadItemStackFromNBT(nbttagcompound1);

						if (inventario[j] != null) {
						}

					}
				}

			}

		}

	}

}

// #########################################################################3

// Sorry i been doing more turn arounds than nesesary coze english is not native languague

what i need is now how to write an NBTTAG compound Back to an Entity

Thanks for reading