I am trying to make a sword that teleports you to a close by but random location like the enderman if you hold the block position

 

It is called in the onEaten method:

@Override
public ItemStack onEaten(ItemStack par1ItemStack, World par2World, EntityPlayer par3EntityPlayer) 
{
	par3EntityPlayer.setPosition(par3EntityPlayer.posX , par3EntityPlayer.posY , par3EntityPlayer.posZ);
	return super.onEaten(par1ItemStack, par2World, par3EntityPlayer);
}

You could use that code or...

player.setPositionAndUpdate(//fields)

You can get a random value (Random.class), and place it in the fields for teleportation like an enderman.