java - What is the default for Optional data members in lombok using @Builder? -

suppose have class such :

@builder class anidentifier {     @nonnull //to indicate required builder     private string mandatoryidpart;      private optional<string> optionalidpart1;     private optional<string> optionalidpart2; } 

when client creates object using builder generated lombok class , not set optional parts, set to? client have pass value wrapped in optional or value builder optional parts?

here's tried out :

public static void main(string[] args) {     anidentifier id = anidentifier.builder().mandatoryidpart("added")                        .optionalidpart1(optional.of("abs")).build(); //line 1     id.optionalidpart2.ispresent(); //line2 } 

firstly line2 generated npe optionalidpart2 set null not optional.empty()
secondly line1, setting optional value required putting string in optional, lombok doesn't take care of that.

so use constructor such annotation:

@builder public anidentifier(@nonnull string mandatoryidpart, string optionalidpart1, string optionalidpart2) {     this.mandatoryidpart = mandatoryidpart;     this.optionalidpart1 = optional.ofnullable(optionalidpart1);     this.optionalidpart2 = optional.ofnullable(optionalidpart2); }