Instanceof syntax error?

I have an exercise which relates to "instanceof" and I am not quite sure how to use it. This is what I came up with: 

for(int i = 4; i < 6; i++){
    int availSupply = part[i].stockLevel+part[i].getAvailForAssembly();
    if(availSupply instanceof Integer){
        System.out.println("Total number of items that can be supplied for "+ part[i].getID()+"(" + part[i].getName() + ": "+ availSupply);
    }
}

The code looks fine to me, however it came up with an error:

Multiple markers at this line

Incompatible conditional operand types int and Integer at:  if(availSupply instanceof Integer){

I do not know what I did wrong, it is the only error that showed up.

Jon Skeet
people
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You can't use instanceof with an expression of a primitive type, as you're doing here with availSupply. An int can't be anything else, after all.

If getAvailForAssembly() is already declared to return int, then you don't need your if statement at all - just unconditionally execute the body. If it returns Integer, you should probably use:

Integer availSupply = ...;
if (availSupply != null) {
    ...
}

people

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