Interface ConstantInstruction

All Superinterfaces:

ClassFileElementPREVIEW, CodeElementPREVIEW, InstructionPREVIEW

All Known Subinterfaces:

ConstantInstruction.ArgumentConstantInstructionPREVIEW, ConstantInstruction.IntrinsicConstantInstructionPREVIEW, ConstantInstruction.LoadConstantInstructionPREVIEW

public sealed interface ConstantInstruction
extends InstructionPREVIEW
permits ConstantInstruction.IntrinsicConstantInstructionPREVIEW, ConstantInstruction.ArgumentConstantInstructionPREVIEW, ConstantInstruction.LoadConstantInstructionPREVIEW

ConstantInstruction is a preview API of the Java platform.

Programs can only use ConstantInstruction when preview features are enabled.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

Models a constant-load instruction in the code array of a Code attribute, including "intrinsic constant" instructions (e.g., iconst_0), "argument constant" instructions (e.g., bipush), and "load constant" instructions (e.g., LDC). Corresponding opcodes will have a kind of Opcode.Kind.CONSTANT^PREVIEW. Delivered as a CodeElement^PREVIEW when traversing the elements of a CodeModel^PREVIEW.

Since:

22

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	ConstantInstruction.ArgumentConstantInstructionPREVIEW	Preview. Models an "argument constant" instruction (e.g., bipush).
static interface	ConstantInstruction.IntrinsicConstantInstructionPREVIEW	Preview. Models an "intrinsic constant" instruction (e.g., iconst_0).
static interface	ConstantInstruction.LoadConstantInstructionPREVIEW	Preview. Models a "load constant" instruction (e.g., ldc).

Method Summary

Modifier and Type	Method	Description
ConstantDesc	constantValue()	Returns the constant value.
static ConstantInstruction.ArgumentConstantInstructionPREVIEW	ofArgument(OpcodePREVIEW op, int value)	Returns an argument constant instruction.
static ConstantInstruction.IntrinsicConstantInstructionPREVIEW	ofIntrinsic(OpcodePREVIEW op)	Returns an intrinsic constant instruction.
static ConstantInstruction.LoadConstantInstructionPREVIEW	ofLoad(OpcodePREVIEW op, LoadableConstantEntryPREVIEW constant)	Returns a load constant instruction.
TypeKindPREVIEW	typeKind()	Returns the type of the constant.

Methods declared in interface java.lang.classfile.Instruction^PREVIEW

opcode, sizeInBytes

Method Details

constantValue

ConstantDesc constantValue()

Returns the constant value.

Returns:

the constant value

typeKind

TypeKindPREVIEW typeKind()

Returns the type of the constant.

Returns:

the type of the constant

ofIntrinsic

static ConstantInstruction.IntrinsicConstantInstructionPREVIEW ofIntrinsic(OpcodePREVIEW op)

Returns an intrinsic constant instruction.

Parameters:

op - the opcode for the specific type of intrinsic constant instruction, which must be of kind Opcode.Kind.CONSTANT^PREVIEW

Returns:

an intrinsic constant instruction

Throws:

IllegalArgumentException - if the opcode does not represent a constant with implicit value

ofArgument

static ConstantInstruction.ArgumentConstantInstructionPREVIEW ofArgument(OpcodePREVIEW op,
 int value)

Returns an argument constant instruction.

Parameters:

op - the opcode for the specific type of argument constant instruction, which must be Opcode.BIPUSH^PREVIEW or Opcode.SIPUSH^PREVIEW

value - the constant value

Returns:

an argument constant instruction

Throws:

IllegalArgumentException - if the opcode is not Opcode.BIPUSH^PREVIEW or Opcode.SIPUSH^PREVIEW, or if the constant value is out of range for the opcode

ofLoad

static ConstantInstruction.LoadConstantInstructionPREVIEW ofLoad(OpcodePREVIEW op,
 LoadableConstantEntryPREVIEW constant)

Returns a load constant instruction.

Parameters:

op - the opcode for the specific type of load constant instruction, which must be of kind Opcode.Kind.CONSTANT^PREVIEW

constant - the constant value

Returns:

a load constant instruction

Throws:

IllegalArgumentException - if the opcode is not Opcode.LDC^PREVIEW, Opcode.LDC_W^PREVIEW, or Opcode.LDC2_W^PREVIEW