Product Version: NetBeans IDE Dev (Build 201606020002)
Java: 1.8.0_92; Java HotSpot(TM) 64-Bit Server VM 25.92-b14
Runtime: Java(TM) SE Runtime Environment 1.8.0_92-b14
System: Windows 10 version 10.0 running on amd64; Cp1252; en_CA (nb)
User directory: C:\Users\Gili\AppData\Roaming\NetBeans\dev
Cache directory: C:\Users\Gili\AppData\Local\NetBeans\Cache\dev

1. Create a new Maven project containing the following code:

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import java.util.List;
import java.util.function.BiConsumer;
import java.util.function.BinaryOperator;
import java.util.function.Supplier;
import java.util.stream.Collector;

public class Main {

    public static class Parent<T, A, R> {

        private final Supplier<A> supplier = null;
    }

    public static class Child<T, A extends List<T>, R extends List<T>>
            extends Parent<T, A, R> {

        public void run() {
            BiConsumer<A, T> accumulator = (list, element) -> {
                list.add(element);
            };
            BinaryOperator<A> combiner = (left, right) -> {
                left.addAll(right);
                return left;
            };

            Collector.of(supplier, accumulator, combiner);
        }
    }
}
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2. Netbeans highlights the last line with a compiler error.
3. When the mouse hovers over the compiler error, the following tooltip is displayed:

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no suitable method found for of(Supplier<A#1>,BiConsumer<A#2,T#1>,BinaryOperator<A#2>)
<followed by 20 confusing lines>
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4. But in fact, javac reports the following errors:

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Main.java:[28,26] supplier has private access in com.mycompany.misleadinggenericerror.Main.Parent

Main.java:[28,22] no suitable method found for of(java.util.function.Supplier<A>,java.util.function.BiConsumer<A,T>,java.util.function.BinaryOperator<A>)
<followed by 20 confusing lines>
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5. The second error message is extremely cryptic and leads to hours of confusion. The first error message is perfectly clear.

The fact that Netbeans lists the second error message and completely omits the first is extremely bad. Prioritizing accordingly.