Java 16
I wish Java had something similar to Properties in Delphi.<p><a href="http://docwiki.embarcadero.com/RADStudio/Sydney/en/Properties_(Delphi)" rel="nofollow">http://docwiki.embarcadero.com/RADStudio/Sydney/en/Propertie...</a><p>You can have Get and Set methods for properties or even allow direct access to the variable itself.<p>type
    TCompass = class(TControl)
      private
         FHeading: THeading;
         procedure SetHeading(Value: THeading);
      published
         property Heading: THeading read FHeading write SetHeading;
         ...
     end;<p>Also, properties can be indexed.<p>type
    TRectangle = class
      private
        FCoordinates: array[0..3] of Longint;
        function GetCoordinate(Index: Integer): Longint;
        procedure SetCoordinate(Index: Integer; Value: Longint);
      public
        property Left: Longint index 0  read GetCoordinate 
                                        write SetCoordinate;
        property Top: Longint index 1   read GetCoordinate 
                                        write SetCoordinate;
        property Right: Longint index 2 read GetCoordinate
                                        write SetCoordinate;
        property Bottom: Longint index 3 read GetCoordinate
                                         write SetCoordinate;
        property Coordinates[Index: Integer]: Longint 
                                        read GetCoordinate
                                        write SetCoordinate;
        ...
    end;<p>Properties can also have "property pages" which can show specific user interfaces for viewing/setting these properties.<p><a href="https://www.delphipower.xyz/guide_8/adding_a_property_page.html" rel="nofollow">https://www.delphipower.xyz/guide_8/adding_a_property_page.h...</a><p>I have yet to see anything of this sophistication in Java or for that matter in any other component framework.