Given a lambda expression that simply returns its input, the editor hints that this parameter is unused.

Given the following example the `collect` method returns a `Collectors.toMap` mapper who returns the input string for the key, the editor will warn that `str' is unused, which in fact it is.

    Map<String, Integer> stringLengths
            = Collections.<String>emptySet().stream()
            .collect(Collectors.toMap(
                            str -> str,
                            str -> str.length()
                    ));

Changing this to an explicit return within a lambda block will prevent the warning.

    Map<String, Integer> stringLengths
            = Collections.<String>emptySet().stream()
            .collect(Collectors.toMap(
                            str -> { return str; },
                            str -> str.length()
                    ));

IMHO any input parameter to a lambda expression should be excluded from this rule as sometimes you may not use one of the input parameters.



Product Version: NetBeans IDE Dev (Build 201401280001)
Java: 1.7.0_51; Java HotSpot(TM) 64-Bit Server VM 24.51-b03
Runtime: Java(TM) SE Runtime Environment 1.7.0_51-b13
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