Module java.base

Package java.lang.classfile^PREVIEW

Interface AttributeMapper<A>

Type Parameters:

A - the attribute type

public interface AttributeMapper<A>

AttributeMapper is a preview API of the Java platform.

Programs can only use AttributeMapper when preview features are enabled.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

Bidirectional mapper between the classfile representation of an attribute and how that attribute is modeled in the API. The attribute mapper is used to parse the classfile representation into a model, and to write the model representation back to a classfile. For each standard attribute, there is a predefined attribute mapper defined in Attributes^PREVIEW. For nonstandard attributes, clients can define their own AttributeMapper^PREVIEW. Classes that model nonstandard attributes should extend CustomAttribute^PREVIEW.

Since:

22

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static enum	AttributeMapper.AttributeStabilityPREVIEW	Preview. Attribute stability indicator

Method Summary

Modifier and Type	Method	Description
default boolean	allowMultiple()	Returns whether this attribute may appear more than once in a given location.
String	name()	Returns the name of the attribute.
A	readAttribute(AttributedElementPREVIEW enclosing, ClassReaderPREVIEW cf, int pos)	Create an AttributePREVIEW instance from a classfile.
AttributeMapper.AttributeStabilityPREVIEW	stability()	Returns attribute stability indicator.
void	writeAttribute(BufWriterPREVIEW buf, A attr)	Write an AttributePREVIEW instance to a classfile.

Method Details

name

String name()

Returns the name of the attribute.

Returns:

the name of the attribute

readAttribute

A readAttribute(AttributedElementPREVIEW enclosing,
 ClassReaderPREVIEW cf,
 int pos)

Create an Attribute^PREVIEW instance from a classfile.

Parameters:

enclosing - The class, method, field, or code attribute in which this attribute appears

cf - The ClassReader^PREVIEW describing the classfile to read from

pos - The offset into the classfile at which the attribute starts

Returns:

the new attribute

writeAttribute

void writeAttribute(BufWriterPREVIEW buf,
 A attr)

Write an Attribute^PREVIEW instance to a classfile.

Parameters:

buf - The BufWriter^PREVIEW to which the attribute should be written

attr - The attribute to write

allowMultiple

default boolean allowMultiple()

Returns whether this attribute may appear more than once in a given location.

Implementation Requirements:

The default implementation returns false

Returns:

whether this attribute may appear more than once in a given location

stability

AttributeMapper.AttributeStabilityPREVIEW stability()

Returns attribute stability indicator.

Returns:

attribute stability indicator