Interface ClassBuilder

All Superinterfaces:: ClassFileBuilder<ClassElement, ClassBuilder>, Consumer<ClassElement>

public sealed interface ClassBuilder extends ClassFileBuilder<ClassElement, ClassBuilder>

A builder for a class file. ClassFile provides different build methods that accept handlers to configure such a builder; ClassFile.build(ClassDesc, Consumer) suffices for basic usage, while ClassFile.build(ClassEntry, ConstantPoolBuilder, Consumer) allows fine-grained control over the constant pool.

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

Since:

See Also:

Method Summary

Modifier and Type	Method	Description
`ClassBuilder`	`transformField(FieldModel field, FieldTransform transform)`	Adds a field by transforming a field from another class.
`ClassBuilder`	`transformMethod(MethodModel method, MethodTransform transform)`	Adds a method by transforming a method from another class.
`default ClassBuilder`	`withField(Utf8Entry name, Utf8Entry descriptor, int flags)`	Adds a field, with only access flags.
`ClassBuilder`	`withField(Utf8Entry name, Utf8Entry descriptor, Consumer<? super FieldBuilder> handler)`	Adds a field.
`default ClassBuilder`	`withField(String name, ClassDesc descriptor, int flags)`	Adds a field, with only access flags.
`default ClassBuilder`	`withField(String name, ClassDesc descriptor, Consumer<? super FieldBuilder> handler)`	Adds a field.
`default ClassBuilder`	`withFlags(int flags)`	Sets the access flags of this class.
`default ClassBuilder`	`withFlags(AccessFlag... flags)`	Sets the access flags of this class.
`default ClassBuilder`	`withInterfaces(ClassEntry... interfaces)`	Sets the interfaces of this class.
`default ClassBuilder`	`withInterfaces(List<ClassEntry> interfaces)`	Sets the interfaces of this class.
`default ClassBuilder`	`withInterfaceSymbols(ClassDesc... interfaces)`	Sets the interfaces of this class.
`default ClassBuilder`	`withInterfaceSymbols(List<ClassDesc> interfaces)`	Sets the interfaces of this class.
`ClassBuilder`	`withMethod(Utf8Entry name, Utf8Entry descriptor, int methodFlags, Consumer<? super MethodBuilder> handler)`	Adds a method.
`default ClassBuilder`	`withMethod(String name, MethodTypeDesc descriptor, int methodFlags, Consumer<? super MethodBuilder> handler)`	Adds a method.
`default ClassBuilder`	`withMethodBody(Utf8Entry name, Utf8Entry descriptor, int methodFlags, Consumer<? super CodeBuilder> handler)`	Adds a method, with only access flags and a `CodeModel`.
`default ClassBuilder`	`withMethodBody(String name, MethodTypeDesc descriptor, int methodFlags, Consumer<? super CodeBuilder> handler)`	Adds a method, with only access flags and a `CodeModel`.
`default ClassBuilder`	`withSuperclass(ClassEntry superclassEntry)`	Sets the superclass of this class.
`default ClassBuilder`	`withSuperclass(ClassDesc desc)`	Sets the superclass of this class.
`default ClassBuilder`	`withVersion(int major, int minor)`	Sets the version of this class.

Methods declared in interface ClassFileBuilder

accept, constantPool, transform, with

Methods declared in interface Consumer

andThen

Method Details

withVersion

default ClassBuilder withVersion(int major, int minor)

Sets the version of this class.

Parameters:

major - the major version number

minor - the minor version number

Returns:

this builder

See Also:

withFlags

default ClassBuilder withFlags(int flags)

Sets the access flags of this class.

Parameters:

flags - the access flags, as a bit mask

Returns:

this builder

See Also:

withFlags

default ClassBuilder withFlags(AccessFlag... flags)

Sets the access flags of this class.

Parameters:

flags - the access flags, as flag enums

Returns:

this builder

Throws:

IllegalArgumentException - if any flag cannot be applied to the AccessFlag.Location.CLASS location

See Also:

withSuperclass

default ClassBuilder withSuperclass(ClassEntry superclassEntry)

Sets the superclass of this class.

Parameters:

superclassEntry - the superclass

Returns:

this builder

See Also:

withSuperclass

default ClassBuilder withSuperclass(ClassDesc desc)

Sets the superclass of this class.

Parameters:

desc - the superclass

Returns:

this builder

Throws:

IllegalArgumentException - if desc represents a primitive type

See Also:

withInterfaces

default ClassBuilder withInterfaces(List<ClassEntry> interfaces)

Sets the interfaces of this class.

Parameters:

interfaces - the interfaces

Returns:

this builder

See Also:

withInterfaces

default ClassBuilder withInterfaces(ClassEntry... interfaces)

Sets the interfaces of this class.

Parameters:

interfaces - the interfaces

Returns:

this builder

See Also:

withInterfaceSymbols

default ClassBuilder withInterfaceSymbols(List<ClassDesc> interfaces)

Sets the interfaces of this class.

Parameters:

interfaces - the interfaces

Returns:

this builder

Throws:

IllegalArgumentException - if any element of interfaces is primitive

See Also:

withInterfaceSymbols

default ClassBuilder withInterfaceSymbols(ClassDesc... interfaces)

Sets the interfaces of this class.

Parameters:

interfaces - the interfaces

Returns:

this builder

Throws:

IllegalArgumentException - if any element of interfaces is primitive

See Also:

withField

ClassBuilder withField(Utf8Entry name, Utf8Entry descriptor, Consumer<? super FieldBuilder> handler)

Adds a field.

Parameters:

name - the field name

descriptor - the field descriptor string

handler - handler to supply the contents of the field

Returns:

this builder

See Also:

withField

default ClassBuilder withField(Utf8Entry name, Utf8Entry descriptor, int flags)

Adds a field, with only access flags.

Parameters:

name - the field name

descriptor - the field descriptor string

flags - the access flags for this field, as a bit mask

Returns:

this builder

See Also:

withField

default ClassBuilder withField(String name, ClassDesc descriptor, Consumer<? super FieldBuilder> handler)

Adds a field.

Parameters:

name - the field name

descriptor - the symbolic field descriptor

handler - handler to supply the contents of the field

Returns:

this builder

See Also:

withField

default ClassBuilder withField(String name, ClassDesc descriptor, int flags)

Adds a field, with only access flags.

Parameters:

name - the field name

descriptor - the symbolic field descriptor

flags - the access flags for this field, as a bit mask

Returns:

this builder

See Also:

transformField

ClassBuilder transformField(FieldModel field, FieldTransform transform)

Adds a field by transforming a field from another class.

This method behaves as if:

withField(field.fieldName(), field.fieldType(),
          fb -> fb.transform(field, transform))

Parameters:

field - the field to be transformed

transform - the transform to apply to the field

Returns:

this builder

See Also:

withMethod

ClassBuilder withMethod(Utf8Entry name, Utf8Entry descriptor, int methodFlags, Consumer<? super MethodBuilder> handler)

Adds a method. The bit for ACC_STATIC flag cannot be modified by the handler later, and must be set through methodFlags.

Parameters:

name - the method name

descriptor - the method descriptor

methodFlags - the access flags as a bit mask, with the


       ACC_STATIC

bit definitely set

handler - handler to supply the contents of the method

Returns:

this builder

See Also:

withMethodBody

default ClassBuilder withMethodBody(Utf8Entry name, Utf8Entry descriptor, int methodFlags, Consumer<? super CodeBuilder> handler)

Adds a method, with only access flags and a CodeModel. The bit for ACC_STATIC flag cannot be modified by the handler later, and must be set through methodFlags.

This method behaves as if:

withMethod(name, descriptor, methodFlags, mb -> mb.withCode(handler))

Parameters:

name - the method name

descriptor - the method descriptor

methodFlags - the access flags as a bit mask, with the


       ACC_STATIC

bit definitely set

handler - handler to supply the contents of the method body

Returns:

this builder

See Also:

withMethod

default ClassBuilder withMethod(String name, MethodTypeDesc descriptor, int methodFlags, Consumer<? super MethodBuilder> handler)

Adds a method. The bit for ACC_STATIC flag cannot be modified by the handler, and must be set through methodFlags.

Parameters:

name - the method name

descriptor - the method descriptor

methodFlags - the access flags as a bit mask, with the


       ACC_STATIC

bit definitely set

handler - handler to supply the contents of the method

Returns:

this builder

See Also:

withMethodBody

default ClassBuilder withMethodBody(String name, MethodTypeDesc descriptor, int methodFlags, Consumer<? super CodeBuilder> handler)

Adds a method, with only access flags and a CodeModel. The bit for ACC_STATIC flag cannot be modified by the handler, and must be set through methodFlags.

This method behaves as if:

withMethod(name, descriptor, methodFlags, mb -> mb.withCode(handler))

Parameters:

name - the method name

descriptor - the method descriptor

methodFlags - the access flags as a bit mask, with the


       ACC_STATIC

bit definitely set

handler - handler to supply the contents of the method body

Returns:

this builder

See Also:

transformMethod

ClassBuilder transformMethod(MethodModel method, MethodTransform transform)

Adds a method by transforming a method from another class. The transform cannot modify the ACC_STATIC flag of the original method.

This method behaves as if:

withMethod(method.methodName(), method.methodType(), method.flags().flagMask(),
           mb -> mb.transform(method, transform))

Parameters:

method - the method to be transformed

transform - the transform to apply to the method

Returns:

this builder

See Also:

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