# Interface UnknownAttribute

All Superinterfaces:
  `Attribute<UnknownAttribute>`, `ClassElement`, `ClassFileElement`, `FieldElement`, `MethodElement`

public sealed interface UnknownAttribute extends Attribute<UnknownAttribute>, ClassElement, MethodElement, FieldElement
Models an unknown attribute read from a `class` file. An attribute is unknown if it is not recognized by one of the mappers in `Attributes` and is not recognized by the `ClassFile.AttributesProcessingOption`.

This attribute is not delivered in the traversal of a `CodeModel`.

An unknown attribute may appear anywhere where an attribute may appear, and has an unknown data dependency.

Since:
  24
See Also:
  - `CustomAttribute`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `byte[]`
  `contents()`
  Returns the uninterpreted contents of the attribute payload.

  ### Methods declared in interface java.lang.classfile.Attribute

  `attributeMapper, attributeName`

- ## Method Details

  - ### contents

    byte[] contents()
    Returns the uninterpreted contents of the attribute payload.
    Returns:
      the uninterpreted contents of the attribute payload