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Interface MethodTransform

All Superinterfaces:: ClassFileTransform<MethodTransform, MethodElement, MethodBuilder>

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 MethodTransform extends ClassFileTransform<MethodTransform, MethodElement, MethodBuilder>

A transformation on streams of MethodElement.

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

A method transform can be lifted to a class transform via ClassTransform.transformingMethods(MethodTransform), transforming only the MethodModel among the class members and passing all other elements to the builders.

Since:

See Also:

Field Summary

Modifier and Type	Field	Description
`static final MethodTransform`	`ACCEPT_ALL`	A method transform that passes all elements to the builder.

Method Summary

Modifier and Type	Method	Description
`default MethodTransform`	`andThen(MethodTransform t)`	Chain this transform with another; elements presented to the builder of this transform will become the input to the next transform.
`static MethodTransform`	`dropping(Predicate<MethodElement> filter)`	Creates a method transform that passes each element through to the builder, except for those that the supplied `Predicate` is true for.
`static MethodTransform`	`endHandler(Consumer<MethodBuilder> finisher)`	Creates a method transform that passes each element through to the builder, and calls the specified function when transformation is complete.
`static MethodTransform`	`ofStateful(Supplier<MethodTransform> supplier)`	Creates a stateful method transform from a `Supplier`.
`static MethodTransform`	`transformingCode(CodeTransform xform)`	Creates a method transform that transforms `CodeModel` elements with the supplied code transform, passing every other element through to the builder.

Methods declared in interface ClassFileTransform

accept, atEnd, atStart

Field Details

ACCEPT_ALL

static final MethodTransform ACCEPT_ALL

A method transform that passes all elements to the builder.

Method Details

ofStateful

static MethodTransform ofStateful(Supplier<MethodTransform> supplier)

Creates a stateful method 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 method transform

endHandler

static MethodTransform endHandler(Consumer<MethodBuilder> finisher)

Creates a method 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 method transform

dropping

static MethodTransform dropping(Predicate<MethodElement> filter)

Creates a method transform that passes each element through to the builder, except for those that the supplied Predicate is true for.

Parameters:: filter - the predicate that determines which elements to drop
Returns:: the method transform

transformingCode

static MethodTransform transformingCode(CodeTransform xform)

Creates a method transform that transforms CodeModel elements with the supplied code transform, passing every other element through to the builder.

Parameters:: xform - the method transform
Returns:: the class transform

andThen

default MethodTransform andThen(MethodTransform 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<MethodTransform, MethodElement, MethodBuilder>
Implementation Requirements:: The default implementation returns this method transform chained with another method 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/MethodTransform.html