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java - Using enum values with J/Link


How can I pass enum values to a function when using J/Link? What is the correct syntax for typing an enum value?



For example, call normalize() using NFC from here.



Answer



Enumeration value names are accessible using LoadJavaClass to load the enum class. However, this particular case is complicated by the fact that the enum class Form is an inner member of the class Normalizer. To load it, we must reference Form by its so-called binary name:


LoadJavaClass["java.text.Normalizer$Form"];

Now we can reference the enum values directly in a call to Normalizer.normalize():


LoadJavaClass["java.text.Normalizer"];

Normalizer`normalize[
MakeJavaObject@FromCharacterCode[{65, 769}],

Normalizer$Form`NFC] // ToCharacterCode

(* {193} *)

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