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Gp 155/random field comparator/completed #137

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Stanislav-Zabramnyi
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@tboychuk tboychuk left a comment

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Please take a look at my comments. Thanks


public RandomFieldComparator(Class<T> targetType) {
Objects.requireNonNull(targetType);
this.targetType = targetType;
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It makes sense to do this.targetType = Objects.requireNonNull(targetType); or even
this.targetType = requireNonNull(targetType);

var field1 = (Comparable) fieldToCompare.get(o1);
var field2 = (Comparable) fieldToCompare.get(o2);

return Comparator.<Comparable>nullsLast(Comparator.naturalOrder()).compare(field1, field2);
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I'd move comparator into a local variable to make this line cleaner.

Objects.requireNonNull(o1);
Objects.requireNonNull(o2);
fieldToCompare.setAccessible(true);

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You user Comparable as raw type (without specifying a generic type), while you can actually provide a type argument and use it property. Both field values have the same type, so you need to create a helper method for compiler to catch that type.

@Override
    public int compare(T o1, T o2) {
        Objects.requireNonNull(o1);
        Objects.requireNonNull(o2);
        return compareFieldValues(o1, o2);
    }

    @SneakyThrows
    @SuppressWarnings("unchecked")
    private <U extends Comparable<? super U>> int compareFieldValues(T o1, T o2) {
        field.setAccessible(true);
        var value1 = (U) field.get(o1);
        var value2 = (U) field.get(o2);
        Comparator<U> comparator = Comparator.nullsLast(Comparator.naturalOrder());
        return comparator.compare(value1, value2);
    }

What I like about helper method is that you can put @SneakyThrows and well as @SuppressWarnings there, which makes method compare clean and simple. 🤷🏻‍♂️

@Stanislav-Zabramnyi Stanislav-Zabramnyi merged commit ee914af into completed Aug 12, 2022
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2 participants