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Can a constructor return null?
It’s not possible for a constructor to return null , and even if an exception would be thrown from the constructor, the next line won’t be called. From section 15.9. 4 of the JLS: The value of a class instance creation expression is a reference to the newly created object of the specified class.
How do I return a null string?
To fix this use an if statement! static String concatAll(Object[] things) { if(things == null) { return null; } …continue code…. This will first check things for a null value BEFORE executing code that could throw an exception. Calling a method on a null object causes a NullPointerException .
What should I return instead of null?
you can usually simply return an empty object instead of null , and it will work fine, without special handling. In these cases, there’s usually no need for the caller to explicitly handle the empty case.
Is returning null bad?
Returning Null is Bad Practice The FirstOrDefault method silently returns null if no order is found in the database. Getting a null value is an ambiguous for caller, because it doesn’t say whether the null is returned due to the bug or due to the fact that the order was not found in the database.
Can a constructor return a value?
Does constructor return any value? There are no “return value” statements in the constructor, but the constructor returns the current class instance. We can write ‘return’ inside a constructor. Like methods, we can overload constructors for creating objects in different ways.
Why returning null is bad?
This is a violation of DRY principle. Getting a null value is an ambiguous for caller, because it doesn’t say whether the null is returned due to the bug or due to the fact that the order was not found in the database. Returning null is definitely not a domain-driven design approach.
Is isEmpty null safe?
6 Answers. No, absolutely not – because if acct is null, it won’t even get to isEmpty it will immediately throw a NullPointerException .
Why return null is bad?
Returning null Creates More Work A function that returns a null reference achieves neither goal. Returning null is like throwing a time bomb into the software. Other code must a guard against null with if and else statements. These extra statements add more complexity to the software.