Detect if player clicks with item such as stick or blaze rod?

how would I detect if player clicks with item such as stick or blaze rod?

I suppose this would use scoreboards?

I also can not use comparators or such, it will all be hooked up to a clock, although there can be commands which are only commenced once at the beginning.

the reason I cant use comparators is because I am creating a one command creation in a generator.

so far I have stared at a wall and tried to think of something.

You can do right click and left click detection, luckily, and 1.9 makes this easier than ever!

Prerequisites:

/scoreboard objectives add rClick stat.talkedToVillager
/scoreboard objectives add holdingBlazeRod dummy
/summon Villager ~ ~ ~ {CustomName:"ClickNpc",ActiveEffects:[{id:14b,Duration:10000,Amplifier:0}],Silent:1b,Offers:{}}

Put this in a clock:

/tp @e[type=Villager,name=ClickNpc] @p
/scoreboard players set @a holdingBlazeRod 0
/scoreboad players set @a holdingBlazeRod 1 {SelectedItem:{id:minecraft:blaze_rod}}

Type this in front of the command you want to execute when blaze rod is right clicked:

/execute @a[score_holdingBlazeRod_min=1,score_rClick_min=1] ~ ~ ~ ...

Done!