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

Modifier and Type	Method	Description
`default void`	`accept(ClassElement e)`	Integrates the member element into the structure being built.
`ConstantPoolBuilder`	`constantPool()`	Returns the constant pool builder associated with this builder.
`default ClassBuilder`	`transform(CompoundElement<ClassElement> model, ClassFileTransform<?, ClassElement, ClassBuilder> transform)`	Applies a transform to a compound structure, directing results to this builder.
`ClassBuilder`	`with(ClassElement e)`	Integrates the member element into the structure being built.

Methods declared in interface Consumer

andThen

Modifier and Type	Method	Description
`default Consumer<ClassElement>`	`andThen(Consumer<? super ClassElement> after)`	Returns a composed `Consumer` that performs, in sequence, this operation followed by the `after` operation.

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

Throws:

IllegalArgumentException - if major or minor is not u2; minor may be

-1

to indicate 65535

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

Throws:

IllegalArgumentException - if flags is not u2

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

Throws:

IllegalArgumentException - if the number of interfaces exceeds the limit of u2

See Also:

withInterfaces

default ClassBuilder withInterfaces(ClassEntry... interfaces)

Sets the interfaces of this class.

Parameters:

interfaces - the interfaces

Returns:

this builder

Throws:

IllegalArgumentException - if the number of interfaces exceeds the limit of u2

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 of interfaces is primitive, or if the number of interfaces exceeds the limit of u2

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 of interfaces is primitive, or if the number of interfaces exceeds the limit of u2

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

Throws:

IllegalArgumentException - if flags is not u2

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

Throws:

IllegalArgumentException - if flags is not u2

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

Throws:

IllegalArgumentException - if methodFlags is not u2

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

Throws:

IllegalArgumentException - if methodFlags is not u2

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

Throws:

IllegalArgumentException - if methodFlags is not u2

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

Throws:

IllegalArgumentException - if methodFlags is not u2

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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