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/OpenJDK 25

Interface CodeTransform

All Superinterfaces:
ClassFileTransform<CodeTransform, CodeElement, CodeBuilder>
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public non-sealed interface CodeTransform extends ClassFileTransform<CodeTransform, CodeElement, CodeBuilder>
A transformation on streams of CodeElement. The stream can come from a CodeModel, or a handler to a CodeBuilder as in CodeBuilder.transforming(CodeTransform, Consumer).

Refer to ClassFileTransform for general guidance and caution around the use of transforms for structures in the class file format.

A code transform can be lifted to a method or a class transform via MethodTransform.transformingCode(CodeTransform) and ClassTransform.transformingMethodBodies(CodeTransform), transforming only the CodeModel within those structures and passing all other elements to the builders.

Since:
24
See Also:

Field Summary

Modifier and Type Field Description
static final CodeTransform ACCEPT_ALL
A code transform that passes all elements to the builder.

Method Summary

Modifier and Type Method Description
default CodeTransform andThen(CodeTransform t)
Chain this transform with another; elements presented to the builder of this transform will become the input to the next transform.
static CodeTransform endHandler(Consumer<CodeBuilder> finisher)
Creates a code transform that passes each element through to the builder, and calls the specified function when transformation is complete.
static CodeTransform ofStateful(Supplier<CodeTransform> supplier)
Creates a stateful code transform from a Supplier.

Methods declared in interface ClassFileTransform

accept, atEnd, atStart

Field Details

ACCEPT_ALL

static final CodeTransform ACCEPT_ALL
A code transform that passes all elements to the builder.

Method Details

ofStateful

static CodeTransform ofStateful(Supplier<CodeTransform> supplier)
Creates a stateful code transform from a Supplier. The supplier will be invoked for each transformation.
Parameters:
supplier - a Supplier that produces a fresh transform object for each traversal
Returns:
the stateful code transform

endHandler

static CodeTransform endHandler(Consumer<CodeBuilder> finisher)
Creates a code transform that passes each element through to the builder, and calls the specified function when transformation is complete.
Parameters:
finisher - the function to call when transformation is complete
Returns:
the code transform

andThen

default CodeTransform andThen(CodeTransform t)
Description copied from interface: ClassFileTransform
Chain this transform with another; elements presented to the builder of this transform will become the input to the next transform.

This method is implemented by the Class-File API. Users usually don't have sufficient access to Class-File API functionalities to override this method correctly for generic downstream transforms.

Specified by:
andThen in interface ClassFileTransform<CodeTransform, CodeElement, CodeBuilder>
Implementation Requirements:
The default implementation returns this code transform chained with another code transform from the argument. Chaining of two transforms requires to involve a chained builder serving as a target builder for this transform and also as a source of elements for the downstream transform.
Parameters:
t - the downstream transform
Returns:
the chained transform

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https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/lang/classfile/CodeTransform.html