CODEWITHSUNDEEP
java
user1100793
user1100793

Reputation: 13

"...cannot be resolved to a variable." Why not?

public int getEntityIndex(String name){ 
    for(int i = 0; i < entities.length; i++){
        if(entities[i].getName().toUpperCase().equals(name.toUpperCase())){
            break;
        }
    }

    return i;
}

This code produces the error: i cannot be resolved to a variable. I'm guessing that variables declared inside the for loop declaration are outside the scope of the remainder of the method, but I was unable to find any information regarding this problem specifically.

After analyzing the code for a while, I am starting to see that using it is a bad idea (what if entities[i] never equals name? The method will return entities.length - 1, even if a match is not found. I think I'll use a while(!found) approach instead.

To clarify, I'm not asking how to fix the issue. I'm asking why this error is occurring.

Thanks!

Upvotes: 0

Views: 326

Answers (8)

Miroslav Siska
Miroslav Siska

Reputation: 401

public int getEntityIndex(String name){ 
    for(int i = 0; i < entities.length; i++){
        if(entities[i].getName().toUpperCase().equals(name.toUpperCase())){
            return i; // If found return [i]
        }
    }
    return -1; //[i] was not found and return = -1;
}

Upvotes: 0

Diego Santamaria
Diego Santamaria

Reputation: 31

You can use another variable to return de value.

public int getEntityIndex(String name){ 
int j = 0;
    for(int i = 0; i < entities.length; i++){
        if(entities[i].getName().toUpperCase().equals(name.toUpperCase())){
            break;
        }
    j++;
    }

return j;}

Upvotes: 0

ParadobC2
ParadobC2

Reputation: 72

The loop and everything is fine, but

return i;

.. i as a variable disappears once it leaves the loop, so the compiler doesn't actually know what to return. Here comes your error message

Upvotes: 0

Francesco Pitzalis
Francesco Pitzalis

Reputation: 2102

You cannot see i outside the for loop.

Try this:

public int getEntityIndex(String name) { 
    for(int i = 0; i < entities.length; i++){
        if(entities[i].getName().toUpperCase().equals(name.toUpperCase())){
            return i;
        }
    }

    return -1;
}

PS: you could also use

entities[i].getName().equalsIgnoreCase(name)

instead of

entities[i].getName().toUpperCase().equals(name.toUpperCase())

Upvotes: 1

giannisf
giannisf

Reputation: 2599

i is declared inside for loop, it's scope is only inside the loop. You cannot return it because its outside of scope.

Upvotes: 0

TangledUpInBlue
TangledUpInBlue

Reputation: 746

In the last line, you return i. The variable i, however, was created inside the scope of a for loop and doesn't exist outside of the for loop where you are trying to return it.

You can return i within the for loop, instead of "break." You would need to return something else at the end.

You could also initialize i outside of the for loop.

Upvotes: 0

Carcigenicate
Carcigenicate

Reputation: 45736

i is only in scope within the for loop. You can't use it outside unless you explicitly extend the scope by either defining i outside of the loop, or assigning it to another variable outside the loop.

Remember, a variable's scope is only within the block that it was defined. You're attempting to return i, but i doesn't exist outside the loop.

Upvotes: 0

Jean Logeart
Jean Logeart

Reputation: 53819

The scope of i is the for loop: i only exists in the for loop.

Therefore, i cannot be used outside of it.

Upvotes: 0

Related Questions