# Class CustomAttribute<T extends CustomAttribute<T>>

java.lang.Object
java.lang.classfile.CustomAttribute<T>

Type Parameters:
  `T` - the custom attribute type

All Implemented Interfaces:
  `Attribute<T>, ClassElement, ClassFileElement, CodeElement, FieldElement, MethodElement`

public abstract non-sealed class CustomAttribute<T extends CustomAttribute<T>> extends Object implements Attribute<T>, CodeElement, ClassElement, MethodElement, FieldElement
Models a user-defined attribute in a `class` file. API models for user-defined attributes should extend this class. A user-defined attribute should also have an `AttributeMapper` defined, which will be returned by `attributeMapper()`, and registered to the `ClassFile.AttributeMapperOption` so the user-defined attributes can be read.

Accessor methods on user-defined attributes read from `class` files may throw `IllegalArgumentException` if the attribute model is lazily evaluated, and the evaluation encounters malformed `class` file format for the attribute.

Since:
  24
See Also:
  - `java.lang.classfile.attribute`

## Constructor Summary

Constructors
Modifier
Constructor
Description
`protected`
`CustomAttribute(AttributeMapper<T> mapper)`
Constructor for subclasses to call.

## Method Summary

Modifier and Type
Method
Description
`final AttributeMapper<T>`
`attributeMapper()`
Returns the `AttributeMapper` associated with this attribute.
`Utf8Entry`
`attributeName()`
Returns the name of the attribute.

### Methods declared in class Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

## Constructor Details

### CustomAttribute

protected CustomAttribute(AttributeMapper<T> mapper)
Constructor for subclasses to call.

Parameters:
  `mapper` - the attribute mapper

## Method Details

### attributeMapper

public final AttributeMapper<T> attributeMapper()
Description copied from interface: `Attribute`
Returns the `AttributeMapper` associated with this attribute.

Specified by:
  `attributeMapper` in interface `Attribute<T extends CustomAttribute<T>>`
Returns:
  the `AttributeMapper` associated with this attribute

### attributeName

public Utf8Entry attributeName()
Returns the name of the attribute. The string value of the name is equivalent to the value of `attributeMapper().name()`.

If this attribute is read from a `class` file, this method returns the `Utf8Entry` indicating the attribute name in the `class` file.

Specified by:
  `attributeName` in interface `Attribute<T extends CustomAttribute<T>>`
Implementation Requirements:
  The default implementation returns a `Utf8Entry` suitable for writing only, which may be unbound. Subclasses representing attributes read from `class` files must override this method.
Returns:
  the name of the attribute
See Also:
  - `AttributeMapper.readAttribute(AttributedElement, ClassReader, int)`