What is Lombok NonNull?
Lombok has always treated multiple annotations usually named @NonNull on a field as a signal to generate a null check if lombok generates an entire method or constructor for you, via e.g. @Data . NonNull on a parameter or logging component results in the null check being inserted at the top of that method.
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What does the javax NonNull annotation do?
@NonNull: The compiler can determine the cases in which a code path can receive a null value, without having to debug a NullPointerException. @ReadOnly – The compiler will flag any attempt to change the object.
What is NonNull?
NonNull() Indicates that the return value of a parameter, field, or method can never be null. This is a marker annotation and has no specific attributes.
What are Lombok annotations?
Lombok is used to reduce boilerplate code for model/data objects, for example you can generate getters and setters for those objects automatically by using Lombok annotations. The easiest way is to use the @Data annotation.
Should I use Lombok NonNull?
Lombok offers the @NonNull annotation which performs the null check and throws an NPE (if not configured differently). The NPE would launch anyway. The only reason here to use the imo annotation is if you want the exception to be something other than an NPE.
What does the @nullable annotation do?
The @Nullable annotation helps you detect: Method calls that may return a null value. Variables (fields, local variables, and parameters), which can be null.
What exception does @NonNull throw?
null pointer exception
The NonNull annotation on the fields will generate a null check for the start of the setter method body and throw a NullPointerException with the appropriate exception message. Making primitive fields @NonNull doesn’t make sense, you’ll get a compiler warning.
How to use Lombok’s non-null annotation in Java?
The Lombok NonNull annotation can be declared on instance fields, methods, and constructor arguments. 1. Lombok @NoNull on fields The NonNull annotation on fields will generate a null check for the start of the setter method body and throw a NullPointerException with the appropriate exception message.
How to generate null check statement in Lombok?
You can use @NonNull in a method or constructor parameter to have lombok generate a null check statement for you. Lombok has always treated various annotations usually called @NonNull on a field as a signal to generate a null check if lombok generates an entire method or constructor for you, via e.g. @Data .
How to use nonnull in Lombok constructor?
You can use @NonNull in a method or constructor parameter to have lombok generate a null check statement for you.
What does the @sneakythrows annotation do in Lombok?
@SneakyThrows is an annotation that could be added to a method that throws a checked exception. This allows you to skip adding the “throws…” clause to the method signature. Any method that then calls this method can use it without having to declare the throws clause, a try and catch, or another @SneakyThrows.