Interface ConstantPoolBuilder

All Superinterfaces:: ConstantPool, Iterable<PoolEntry>

public sealed interface ConstantPoolBuilder extends ConstantPool

Builder for the constant pool of a class file. Provides read and write access to the constant pool that is being built. Writing is append-only (the index of new entries monotonically increase) and idempotent (entry-bearing methods will return an existing entry if there is a suitable one).

For class file building, an overload of ClassFile::build takes a ConstantPoolBuilder. For class file transformations via ClassFile::transformClass, the ClassFile.ConstantPoolSharingOption controls how the constant pool builder of the resulting class is created.

Alien Constant Pool Entries

In class file building and constant pool building, some constant pool entries supplied may be alien to this constant pool builder of the active class file builder. For example, classEntry(Utf8Entry) may be called with an alien UTF8 entry. Alien entries will be converted to a pool entry in this constant pool builder, reusing equivalent entries or adding new entries if there is none. As a result, all pool entries returned by entry-bearing methods in this constant pool builder belong to this constant pool.

Some ClassFileBuilder methods may have their outputs adjusted if they receive pool entries alien to their constant pools. For example, if an ldc_w instruction with an alien entry is written to a CodeBuilder, the CodeBuilder may emit a functionally equivalent ldc instruction instead, if the converted entry can be encoded in such an instruction.

To avoid the conversion of alien constant pool entries, such as for the accuracy of the generated class file, users can always supply constant pool entries obtained by calling the constant pool builder entry-bearing methods of the constant pools associated with the ClassFileBuilder. Otherwise, the conversions have no impact on the behaviors of the generated class files.

Since:

See Also:

Method Summary

Modifier and Type	Method	Description
`BootstrapMethodEntry`	`bsmEntry(MethodHandleEntry methodReference, List<LoadableConstantEntry> arguments)`	Returns a `BootstrapMethodEntry` referring to a `MethodHandleEntry` and a list of `LoadableConstantEntry`.
`default BootstrapMethodEntry`	`bsmEntry(DirectMethodHandleDesc methodReference, List<ConstantDesc> arguments)`	Returns a `BootstrapMethodEntry` describing the provided bootstrap method and arguments.
`boolean`	`canWriteDirect(ConstantPool constantPool)`	Returns `true` if the index of any entry in the given constant pool refers to the same entry in this builder.
`ClassEntry`	`classEntry(Utf8Entry ne)`	Returns a `ClassEntry` referring to the provided `Utf8Entry`.
`default ClassEntry`	`classEntry(ClassDesc classDesc)`	Returns a `ClassEntry` describing the same reference type as the provided `ClassDesc`.
`ConstantDynamicEntry`	`constantDynamicEntry(BootstrapMethodEntry bootstrapMethodEntry, NameAndTypeEntry nameAndType)`	Returns a `ConstantDynamicEntry` referring to a `BootstrapMethodEntry` and a `NameAndTypeEntry`.
`default ConstantDynamicEntry`	`constantDynamicEntry(DynamicConstantDesc<?> dcd)`	Returns a `ConstantDynamicEntry` describing the dynamic constant as the provided `DynamicConstantDesc`.
`default ConstantValueEntry`	`constantValueEntry(ConstantDesc c)`	Returns a `ConstantValueEntry` describing the provided constant `Integer`, `Long`, `Float`, `Double`, or `String` value.
`DoubleEntry`	`doubleEntry(double value)`	Returns a `DoubleEntry` describing the provided value.
`FieldRefEntry`	`fieldRefEntry(ClassEntry owner, NameAndTypeEntry nameAndType)`	Returns a `FieldRefEntry` referring to a `ClassEntry` and a `NameAndTypeEntry`.
`default FieldRefEntry`	`fieldRefEntry(ClassDesc owner, String name, ClassDesc type)`	Returns a `FieldRefEntry` describing a field of a class.
`FloatEntry`	`floatEntry(float value)`	Returns a `FloatEntry` describing the provided value.
`IntegerEntry`	`intEntry(int value)`	Returns an `IntegerEntry` describing the provided value.
`InterfaceMethodRefEntry`	`interfaceMethodRefEntry(ClassEntry owner, NameAndTypeEntry nameAndType)`	Returns an `InterfaceMethodRefEntry` referring to a `ClassEntry` and a `NameAndTypeEntry`.
`default InterfaceMethodRefEntry`	`interfaceMethodRefEntry(ClassDesc owner, String name, MethodTypeDesc type)`	Returns an `InterfaceMethodRefEntry` describing a method of an interface.
`InvokeDynamicEntry`	`invokeDynamicEntry(BootstrapMethodEntry bootstrapMethodEntry, NameAndTypeEntry nameAndType)`	Returns an `InvokeDynamicEntry` referring to a `BootstrapMethodEntry` and a `NameAndTypeEntry`.
`default InvokeDynamicEntry`	`invokeDynamicEntry(DynamicCallSiteDesc dcsd)`	Returns an `InvokeDynamicEntry` describing the same dynamic call site as the provided `DynamicCallSiteDesc`.
`default LoadableConstantEntry`	`loadableConstantEntry(ConstantDesc c)`	Returns a `LoadableConstantEntry` describing the provided constant value.
`LongEntry`	`longEntry(long value)`	Returns a `LongEntry` describing the provided value.
`MethodHandleEntry`	`methodHandleEntry(int refKind, MemberRefEntry reference)`	Returns a `MethodHandleEntry` encoding a reference kind and referring to a `MemberRefEntry`.
`default MethodHandleEntry`	`methodHandleEntry(DirectMethodHandleDesc descriptor)`	Returns a `MethodHandleEntry` describing the same method handle as the given `DirectMethodHandleDesc`.
`MethodRefEntry`	`methodRefEntry(ClassEntry owner, NameAndTypeEntry nameAndType)`	Returns a `MethodRefEntry` referring to a `ClassEntry` and a `NameAndTypeEntry`.
`default MethodRefEntry`	`methodRefEntry(ClassDesc owner, String name, MethodTypeDesc type)`	Returns a `MethodRefEntry` describing a method of a class.
`MethodTypeEntry`	`methodTypeEntry(Utf8Entry descriptor)`	Returns a `MethodTypeEntry` referring to a `Utf8Entry`.
`MethodTypeEntry`	`methodTypeEntry(MethodTypeDesc descriptor)`	Returns a `MethodTypeEntry` describing the same method type as the provided `MethodTypeDesc`.
`ModuleEntry`	`moduleEntry(Utf8Entry moduleName)`	Returns a `ModuleEntry` referring to the provided `Utf8Entry`.
`default ModuleEntry`	`moduleEntry(ModuleDesc moduleDesc)`	Returns a `ModuleEntry` describing the same module as the provided `ModuleDesc`.
`NameAndTypeEntry`	`nameAndTypeEntry(Utf8Entry nameEntry, Utf8Entry typeEntry)`	Returns a `NameAndTypeEntry` referring to the provided name and type `Utf8Entry`.
`default NameAndTypeEntry`	`nameAndTypeEntry(String name, ClassDesc type)`	Returns a `NameAndTypeEntry` describing the provided unqualified name and field descriptor.
`default NameAndTypeEntry`	`nameAndTypeEntry(String name, MethodTypeDesc type)`	Returns a `NameAndTypeEntry` describing the provided name and method descriptor.
`static ConstantPoolBuilder`	`of()`	Returns a new constant pool builder.
`static ConstantPoolBuilder`	`of(ClassModel classModel)`	Returns a new constant pool builder.
`PackageEntry`	`packageEntry(Utf8Entry nameEntry)`	Returns a `PackageEntry` referring to the provided `Utf8Entry`.
`default PackageEntry`	`packageEntry(PackageDesc packageDesc)`	Returns a `PackageEntry` describing the same package as the provided `PackageDesc`.
`StringEntry`	`stringEntry(Utf8Entry utf8)`	Returns a `StringEntry` referring to a `Utf8Entry`.
`default StringEntry`	`stringEntry(String value)`	Returns a `StringEntry` describing the provided value.
`default Utf8Entry`	`utf8Entry(ClassDesc desc)`	Returns a `Utf8Entry` describing the field descriptor string of the provided `ClassDesc`.
`default Utf8Entry`	`utf8Entry(MethodTypeDesc desc)`	Returns a `Utf8Entry` describing the method descriptor string of the provided `MethodTypeDesc`.
`Utf8Entry`	`utf8Entry(String s)`	Returns a `Utf8Entry` describing the provided `String`.

Methods declared in interface ConstantPool

bootstrapMethodCount, bootstrapMethodEntry, entryByIndex, entryByIndex, iterator, size

Modifier and Type	Method	Description
`int`	`bootstrapMethodCount()`	Returns the number of entries in the bootstrap method table.
`BootstrapMethodEntry`	`bootstrapMethodEntry(int index)`	Returns the `BootstrapMethodEntry` at the specified index within the bootstrap method table.
`PoolEntry`	`entryByIndex(int index)`	Returns the entry at the specified index.
`<T extends PoolEntry> T`	`entryByIndex(int index, Class<T> cls)`	Returns the entry of a given type at the specified index.
`default Iterator<PoolEntry>`	`iterator()`	Returns an iterator over pool entries.
`int`	`size()`	Returns the exclusive upper bound of the valid indices of this constant pool.

Methods declared in interface Iterable

forEach, spliterator

Modifier and Type	Method	Description
`default void`	`forEach(Consumer<? super PoolEntry> action)`	Performs the given action for each element of the `Iterable` until all elements have been processed or the action throws an exception.
`default Spliterator<PoolEntry>`	`spliterator()`	Creates a `Spliterator` over the elements described by this `Iterable`.

Method Details

of

static ConstantPoolBuilder of(ClassModel classModel)

Returns a new constant pool builder. The new constant pool builder will be pre-populated with the contents of the constant pool associated with the given class model. The index of new entries will start from the size() of the source pool.

Parameters:

classModel - the class to copy from

Returns:

a new constant pool builder

See Also:

of

static ConstantPoolBuilder of()

Returns a new constant pool builder. The new constant pool builder will be empty. The index of new entries will start from 1.

Returns:

a new constant pool builder

See Also:

canWriteDirect

boolean canWriteDirect(ConstantPool constantPool)

Returns true if the index of any entry in the given constant pool refers to the same entry in this builder. This may be because they are the same builder, or because this builder was pre-populated from the given constant pool.

If the constant pool of an entry is not directly writable to this pool, it is alien to this pool, and a ClassFileBuilder associated with this constant pool will convert that alien constant pool entry.

Parameters:

constantPool - the given constant pool

Returns:

true if the index of any entry in the given constant pool refers to the same entry in this builder

See Also:

utf8Entry

Utf8Entry utf8Entry(String s)

Returns a Utf8Entry describing the provided String.

Parameters:

s - the string

Returns:

a Utf8Entry describing the provided String

See Also:

utf8Entry

default Utf8Entry utf8Entry(ClassDesc desc)

Returns a Utf8Entry describing the field descriptor string of the provided ClassDesc.

API Note:: The resulting Utf8Entry is usually not referable by a ClassEntry, which uses internal form of binary names.
Parameters:: desc - the symbolic descriptor for the class
Returns:: a Utf8Entry describing the field descriptor string of the provided ClassDesc

utf8Entry

default Utf8Entry utf8Entry(MethodTypeDesc desc)

Returns a Utf8Entry describing the method descriptor string of the provided MethodTypeDesc.

Parameters:: desc - the symbolic descriptor for the method type
Returns:: a Utf8Entry describing the method descriptor string of the provided MethodTypeDesc

classEntry

ClassEntry classEntry(Utf8Entry ne)

Returns a ClassEntry referring to the provided Utf8Entry. The Utf8Entry describes the internal form of the binary name of a class or interface or the field descriptor string of an array type.

Parameters:

ne - the Utf8Entry

Returns:

a ClassEntry referring to the provided Utf8Entry

See Also:

classEntry

default ClassEntry classEntry(ClassDesc classDesc)

Returns a ClassEntry describing the same reference type as the provided ClassDesc.

Parameters:

classDesc - the symbolic descriptor for the reference type

Returns:

a ClassEntry describing the same reference type as the provided ClassDesc

Throws:

IllegalArgumentException - if classDesc represents a primitive type

See Also:

packageEntry

PackageEntry packageEntry(Utf8Entry nameEntry)

Returns a PackageEntry referring to the provided Utf8Entry. The Utf8Entry describes the internal form of the name of a package.

Parameters:

nameEntry - the Utf8Entry

Returns:

a PackageEntry referring to the provided Utf8Entry

See Also:

packageEntry

default PackageEntry packageEntry(PackageDesc packageDesc)

Returns a PackageEntry describing the same package as the provided PackageDesc.

Parameters:

packageDesc - the symbolic descriptor for the package

Returns:

a PackageEntry describing the same package as the provided PackageDesc

See Also:

moduleEntry

ModuleEntry moduleEntry(Utf8Entry moduleName)

Returns a ModuleEntry referring to the provided Utf8Entry. The Utf8Entry describes the module name.

Parameters:

moduleName - the constant pool entry describing the module name

Returns:

a ModuleEntry referring to the provided Utf8Entry

See Also:

moduleEntry

default ModuleEntry moduleEntry(ModuleDesc moduleDesc)

Returns a ModuleEntry describing the same module as the provided ModuleDesc.

Parameters:

moduleDesc - the symbolic descriptor for the module

Returns:

a ModuleEntry describing the same module as the provided ModuleDesc

See Also:

nameAndTypeEntry

NameAndTypeEntry nameAndTypeEntry(Utf8Entry nameEntry, Utf8Entry typeEntry)

Returns a NameAndTypeEntry referring to the provided name and type Utf8Entry. The name Utf8Entry describes an unqualified name or the special name "<init>", and the type Utf8Entry describes a field or method descriptor string.

Parameters:

nameEntry - the name Utf8Entry

typeEntry - the type Utf8Entry

Returns:

a NameAndTypeEntry referring to the provided name and type Utf8Entry

See Also:

nameAndTypeEntry

default NameAndTypeEntry nameAndTypeEntry(String name, ClassDesc type)

Returns a NameAndTypeEntry describing the provided unqualified name and field descriptor.

Parameters:: name - the unqualified name; type - the field descriptor
Returns:: a NameAndTypeEntry describing the provided unqualified name and field descriptor

nameAndTypeEntry

default NameAndTypeEntry nameAndTypeEntry(String name, MethodTypeDesc type)

Returns a NameAndTypeEntry describing the provided name and method descriptor. The name can be an unqualified name or the special name "<init>".

Parameters:: name - the unqualified name, or "<init>"; type - the method descriptor
Returns:: a NameAndTypeEntry describing the provided name and method descriptor

fieldRefEntry

FieldRefEntry fieldRefEntry(ClassEntry owner, NameAndTypeEntry nameAndType)

Returns a FieldRefEntry referring to a ClassEntry and a NameAndTypeEntry. The ClassEntry describes a class or interface that has this field as a member, and the


NameAndTypeEntry

describes the unqualified name and the field descriptor for this field.

Parameters:

owner - the ClassEntry

nameAndType - the NameAndTypeEntry

Returns:

a FieldRefEntry referring to a ClassEntry and a NameAndTypeEntry

See Also:

fieldRefEntry

default FieldRefEntry fieldRefEntry(ClassDesc owner, String name, ClassDesc type)

Returns a FieldRefEntry describing a field of a class.

Parameters:

owner - the class or interface the field is a member of

name - the unqualified name of the field

type - the field descriptor

Returns:

a FieldRefEntry describing a field of a class

Throws:

IllegalArgumentException - if owner represents a primitive type

See Also:

methodRefEntry

MethodRefEntry methodRefEntry(ClassEntry owner, NameAndTypeEntry nameAndType)

Returns a MethodRefEntry referring to a ClassEntry and a NameAndTypeEntry. The ClassEntry describes a class that has this method as a member, and the NameAndTypeEntry describes the unqualified name or the special name "<init>" and the method descriptor for this method.

Parameters:

owner - the ClassEntry

nameAndType - the NameAndTypeEntry

Returns:

a MethodRefEntry referring to a ClassEntry and a NameAndTypeEntry

See Also:

methodRefEntry

default MethodRefEntry methodRefEntry(ClassDesc owner, String name, MethodTypeDesc type)

Returns a MethodRefEntry describing a method of a class.

Parameters:

owner - the class the method is a member of

name - the unqualified name, or special name "<init>", of the method

type - the method descriptor

Returns:

a MethodRefEntry describing a method of a class

Throws:

IllegalArgumentException - if owner represents a primitive type

See Also:

interfaceMethodRefEntry

InterfaceMethodRefEntry interfaceMethodRefEntry(ClassEntry owner, NameAndTypeEntry nameAndType)

Returns an InterfaceMethodRefEntry referring to a ClassEntry and a NameAndTypeEntry. The ClassEntry describes an interface that has this method as a member, and the


NameAndTypeEntry

describes the unqualified name and the method descriptor for this method.

Parameters:

owner - the ClassEntry

nameAndType - the NameAndTypeEntry

Returns:

an InterfaceMethodRefEntry referring to a ClassEntry and a NameAndTypeEntry

See Also:

interfaceMethodRefEntry

default InterfaceMethodRefEntry interfaceMethodRefEntry(ClassDesc owner, String name, MethodTypeDesc type)

Returns an InterfaceMethodRefEntry describing a method of an interface.

Parameters:

owner - the interface the method is a member of

name - the unqualified name of the method

type - the method descriptor

Returns:

an InterfaceMethodRefEntry describing a method of an interface

Throws:

IllegalArgumentException - if owner represents a primitive type

See Also:

methodTypeEntry

MethodTypeEntry methodTypeEntry(MethodTypeDesc descriptor)

Returns a MethodTypeEntry describing the same method type as the provided MethodTypeDesc.

Parameters:

descriptor - the symbolic descriptor of the method type

Returns:

a MethodTypeEntry describing the same method type as the provided MethodTypeDesc

See Also:

methodTypeEntry

MethodTypeEntry methodTypeEntry(Utf8Entry descriptor)

Returns a MethodTypeEntry referring to a Utf8Entry. The Utf8Entry represents a method descriptor string.

Parameters:

descriptor - the Utf8Entry

Returns:

a MethodTypeEntry referring to a Utf8Entry

See Also:

methodHandleEntry

default MethodHandleEntry methodHandleEntry(DirectMethodHandleDesc descriptor)

Returns a MethodHandleEntry describing the same method handle as the given DirectMethodHandleDesc.

Parameters:

descriptor - the symbolic descriptor of the method handle

Returns:

a MethodHandleEntry describing the same method handle as the given DirectMethodHandleDesc

See Also:

methodHandleEntry

MethodHandleEntry methodHandleEntry(int refKind, MemberRefEntry reference)

Returns a MethodHandleEntry encoding a reference kind and referring to a MemberRefEntry. The reference kind is in [1, 9], and the MemberRefEntry is subject to various restrictions based on the reference kind (JVMS Â§4.4.8).

Parameters:

refKind - the reference kind of the method handle

reference - the MemberRefEntry

Returns:

a MethodHandleEntry encoding a reference kind and referring to a MemberRefEntry

Throws:

IllegalArgumentException - if refKind is not u1

See Also:

invokeDynamicEntry

default InvokeDynamicEntry invokeDynamicEntry(DynamicCallSiteDesc dcsd)

Returns an InvokeDynamicEntry describing the same dynamic call site as the provided DynamicCallSiteDesc.

Parameters:

dcsd - the symbolic descriptor of the dynamic call site

Returns:

an InvokeDynamicEntry describing the same dynamic call site as the provided DynamicCallSiteDesc

See Also:

invokeDynamicEntry

InvokeDynamicEntry invokeDynamicEntry(BootstrapMethodEntry bootstrapMethodEntry, NameAndTypeEntry nameAndType)

Returns an InvokeDynamicEntry referring to a BootstrapMethodEntry and a NameAndTypeEntry. The BootstrapMethodEntry describes the bootstrap method and its invocation arguments in addition to the name and type, and the NameAndTypeEntry a name and a method descriptor.

Parameters:

bootstrapMethodEntry - the BootstrapMethodEntry

nameAndType - the NameAndTypeEntry

Returns:

an InvokeDynamicEntry referring to a BootstrapMethodEntry and a NameAndTypeEntry

See Also:

constantDynamicEntry

default ConstantDynamicEntry constantDynamicEntry(DynamicConstantDesc<?> dcd)

Returns a ConstantDynamicEntry describing the dynamic constant as the provided DynamicConstantDesc.

Parameters:

dcd - the symbolic descriptor of the constant

Returns:

a ConstantDynamicEntry describing the dynamic constant as the provided DynamicConstantDesc

See Also:

constantDynamicEntry

ConstantDynamicEntry constantDynamicEntry(BootstrapMethodEntry bootstrapMethodEntry, NameAndTypeEntry nameAndType)

Returns a ConstantDynamicEntry referring to a BootstrapMethodEntry and a NameAndTypeEntry. The BootstrapMethodEntry describes the bootstrap method and its invocation arguments in addition to the name and type, and the NameAndTypeEntry a name and a field descriptor.

Parameters:

bootstrapMethodEntry - the BootstrapMethodEntry

nameAndType - the NameAndTypeEntry

Returns:

a ConstantDynamicEntry referring to a BootstrapMethodEntry and a NameAndTypeEntry

See Also:

intEntry

IntegerEntry intEntry(int value)

Returns an IntegerEntry describing the provided value.

Parameters:

value - the value

Returns:

an IntegerEntry describing the provided value

See Also:

floatEntry

FloatEntry floatEntry(float value)

Returns a FloatEntry describing the provided value.

All NaN values of the float may or may not be collapsed into a single "canonical" NaN value.

Parameters:

value - the value

Returns:

a FloatEntry describing the provided value

See Also:

longEntry

LongEntry longEntry(long value)

Returns a LongEntry describing the provided value.

Parameters:

value - the value

Returns:

a LongEntry describing the provided value

See Also:

doubleEntry

DoubleEntry doubleEntry(double value)

Returns a DoubleEntry describing the provided value.

All NaN values of the double may or may not be collapsed into a single "canonical" NaN value.

Parameters:

value - the value

Returns:

a DoubleEntry describing the provided value

See Also:

stringEntry

StringEntry stringEntry(Utf8Entry utf8)

Returns a StringEntry referring to a Utf8Entry. The Utf8Entry describes the string value.

Parameters:

utf8 - the Utf8Entry

Returns:

a StringEntry referring to a Utf8Entry

See Also:

stringEntry

default StringEntry stringEntry(String value)

Returns a StringEntry describing the provided value.

Parameters:

value - the value

Returns:

a StringEntry describing the provided value

See Also:

constantValueEntry

default ConstantValueEntry constantValueEntry(ConstantDesc c)

Returns a ConstantValueEntry describing the provided constant Integer, Long, Float, Double, or String value.

Parameters:

c - the provided constant value

Returns:

a ConstantValueEntry describing the provided constant Integer, Long, Float, Double, or String value

Throws:

IllegalArgumentException - if the value is not one of


        Integer

, Long, Float, Double, or


        String

See Also:

loadableConstantEntry

default LoadableConstantEntry loadableConstantEntry(ConstantDesc c)

Returns a LoadableConstantEntry describing the provided constant value.

Parameters:: c - the nominal descriptor for the constant
Returns:: a LoadableConstantEntry describing the provided constant value

bsmEntry

default BootstrapMethodEntry bsmEntry(DirectMethodHandleDesc methodReference, List<ConstantDesc> arguments)

Returns a BootstrapMethodEntry describing the provided bootstrap method and arguments.

Parameters:: methodReference - the bootstrap method; arguments - the arguments
Returns:: a BootstrapMethodEntry describing the provided bootstrap method and arguments
Throws:: IllegalArgumentException - if the number of arguments exceeds the limit of u2

bsmEntry

BootstrapMethodEntry bsmEntry(MethodHandleEntry methodReference, List<LoadableConstantEntry> arguments)

Returns a BootstrapMethodEntry referring to a MethodHandleEntry and a list of LoadableConstantEntry. The MethodHandleEntry is the bootstrap method, and the list of LoadableConstantEntry is the arguments.

Parameters:

methodReference - the MethodHandleEntry

arguments - the list of LoadableConstantEntry

Returns:

a BootstrapMethodEntry referring to a MethodHandleEntry and a list of LoadableConstantEntry

Throws:

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

See Also:

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