Product Version = NetBeans IDE 8.0 (Build 201403101706)
Operating System = Windows 8 version 6.2 running on amd64
Java; VM; Vendor = 1.8.0
Runtime = Java HotSpot(TM) 64-Bit Server VM 25.0-b70

Consider this class (imply an import for java.util.concurrent.Callable):

class MissingThrowsDeclarationWhenConvertingLambdaExpressionToAnonymousInnerClass {
    void bug() {
        java.util.concurrent.Callable<String> c = () -> {
            throw new Exception();
        };
    }
}

It compiles fine because Callable<V>'s method is declared as: V call() throws Exception;

NetBeans suggests "Use anonymous inner class" which results in:

class MissingThrowsDeclarationWhenConvertingLambdaExpressionToAnonymousInnerClass {
    void bug() {
        Callable<String> c = new Callable<String>() {
            public String call() {
                throw new Exception(); // "unreported exception Exception; must be caught or declared to be thrown"
            }
        };
    }
}

It does not add a throws declaration, therefore resulting in a compiler error.