[Solved] Java 8 Optional get
Use .orElse(null) if you want null. The idea of Optional is to force you to explicitly handle the absence of the value. 0 solved Java 8 Optional get
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[Solved] Is there a way to combine Java8 Optional returning a value with printing a message on null?
Use orElseGet: Optional<String> startingOptional = getMyOptional(); String finishingValue = startingOptional.orElseGet(() -> { System.out.println(“value not found”); return “”; }); Using .map(value -> value) is useless: transforming a value into itself doesn’t change anything. solved Is there a way to combine Java8 Optional returning a value with printing a message on null?
[Solved] Java 8 Optional get() method [closed]
loginUser.ifPresent(user -> { user.setLastLogin(new Date()); userService.saveUser(user); }); More elegant. Here’s more to the topic: isPresent() is bad for you. 1 solved Java 8 Optional get() method [closed]
[Solved] Is the implementation of “ based on `fmap` special to Maybe applicative or can it be generalized to other applicatives?
Is the implementation of “ based on `fmap` special to Maybe applicative or can it be generalized to other applicatives? solved Is the implementation of “ based on `fmap` special to Maybe applicative or can it be generalized to other applicatives?
[Solved] swift How to determine if a variable is an optional
As an academic exercise (can it be done vs. should it be done), I came up with this: func isOptional(a: Any) -> Bool { return “\(a.dynamicType)”.hasPrefix(“Swift.Optional”) } Example: let name = “Fred” let oname: String? = “Jones” let age = 37 let oage: Int? = 38 let arr: [Any] = [name, oname, age, oage] for … Read more
[Solved] Error while throwing User defined exception using orElseThrow in java 8 [duplicate]
it should be a supplier: .orElseThrow(() -> new UserNotFoundException(“User doesnt exist in system”)); 0 solved Error while throwing User defined exception using orElseThrow in java 8 [duplicate]
[Solved] Xcode unexpectedly found nil while unwrapping an Optional, but no idea why
Solved it. As the comments pointed out, the problem was that I was not accessing ViewController correctly. In order to access my ViewController outside of the ViewController class, I was creating a new instance of it by ViewController(). I solved it by putting the function inside the class and changing ViewController() part to self.ViewController. This … Read more