我是初学者。我必须实现一种根据给定比较器查找流的最小和最大元素的方法。如果流不包含任何元素,请调用:
minMaxConsumer.accept(null, null);
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我无法调用:
minMaxConsumer.accept(test.min(order), test.max(order));
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码:
public static <T> void findMinMax(
Stream<? extends T> stream,
Comparator<? super T> order,
BiConsumer<? super T, ? super T> minMaxConsumer) {
Stream<T> test = Stream.concat(Stream.empty(),stream);
if(test.count()==0)
{
minMaxConsumer.accept(null, null);
}
else
{
minMaxConsumer.accept(test.min(order), test.max(order));
}
}
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错误:
Compilation error
Main.java:12: error: incompatible types: Optional<T> cannot be converted to CAP#1
minMaxConsumer.accept(test.min(order), test.max(order));
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