Optimizing code for more clearness and efficiency

Question

This code works fine, but I need to simplify it for more clearness and hopefully more efficiency:

int i = 0;

if (p.cap()) n++;
if (p.creditcard()) n++;
if (p.email()) n++;
[...]
if (p.price()) n++;
if (p.url()) n++;
if (p.zip()) n++;

if (n == 0) p.standard();

As the code says, I need to call multiple methods (I don't know the finite number of them). Every p. ()* method returns a boolean value, and n is incremented only if the value returned is true. If n==0 (this happens when EVERY method called returns false) then I need to call p.standard() .

How can I write a more clear and efficient code? I tried with the or condition , something like this:

if (!( p.cap() || p.email() || p.isbn() || p.number() || p.phone() ||
       p.price() || p.time() || p.url() || p.zip() || p.creditcard()
    )) {
        p.standard();
}

But obviously it didn't work properly (example: if p.cap() returns true the other methods are not called).

I need to call every method.

Answer 1

You did not specify if every method has to be called, but it seems you want to call them all regardless of individual results. So use the simple or operator: | (not the short circuit or ||).

if (!( p.cap() | p.email() | p.isbn() | p.number() | p.phone() |
   p.price() | p.time() | p.url() | p.zip() | p.creditcard()
    )) {
        p.standard();
}

Answer 2

With some boilerplate, you could abstract this into some sort of validator interface:

interface Validator {
    boolean validate(Foo p);
}

Validator[] validators = new Validator[] {
    new Validator() { boolean validate(Foo p) {return p.cap();} },
    new Validator() { boolean validate(Foo p) {return p.creditcard ();} },
    new Validator() { boolean validate(Foo p) {return p.email();} },
    // …
}

public int validateAll(Foo p, Validator[] validators) {
    int valid = 0;
    for (Validator v : validators) {
        if (v.validate(p)) valid++;
    }
    return valid;
}

if (validateAll(p, validators)) p.standard();

This is a net increase in code, but it has the advantage of communicating "run all these checks on p " clearly, and the list of checks is extensible.

(I admit this might easily be a solution that's way too heavy for your needs.)

Answer 3

really hard to do here - not enough context...

but make a new method on the p object that returns the value you are looking for... then call it from the place where all this code is now.

something like

int n = p.getPopulatedColumns();

then inside that method, it doesnt matter that much what the implementation is - because the reader will know the intent.

Answer 4

There is another quite elegant solution IMO.

Create a validate method like this:

public static int validate(boolean ... booleans) {
    int n = 0;
    for (boolean b : booleans) {
        if (b) n++;
    }
    return n;
}

Then you can call this method like this:

int n = validate(p.cap(), p.creditcard(), p.email());
if (n == 0) p.standard();

Since the validate method takes the booleans as variadics you can add as many (or as few) arguments as you want.

Or maybe you can simplify to return a boolean if all arguments are false:

public static boolean validate(boolean ... booleans) {
    int n = 0;
    for (boolean b : booleans) {
        if (b) n++;
    }
    return 0 == n;
}

That all depends on if you need the n variable later on or not.