Can I Use Constant Arrays or Strings as Annotation Parameters in Java?

Using Constant Values in Annotation Parameters

Annotating classes with constant values can streamline code, but Java presents challenges in this regard. Annotations are resolved at compile time, potentially prohibiting the use of constant arrays or Strings in annotation parameters.

To address this, Java only allows compile constants, which include primitives and Strings. Annotations must adhere to the following constant expression requirements:

• Literals of primitive or String types
• Casts to these types
• Parentheses around constant expressions
• References to constant variables (simple or qualified)

Unfortunately, this means that using an array constant like FieldValues.FIELD1 within an annotation is not possible. Despite its appearance as a constant, an array in Java is not protected from modification, rendering it unsuitable for constant expressions.

Therefore, in Java, it is not possible to directly supply a constant array or String constant as an annotation parameter. Developers must specify the values explicitly within the annotation definition.

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