Models a constant-load instruction in the code array of a Code attribute, including "intrinsic", "argument", and "load" constant instructions. Corresponding opcodes have a kind of Opcode.Kind#CONSTANT. Delivered as a CodeElement when traversing the elements of a CodeModel.

The loaded constant value is symbolically represented as a ConstantDesc:

ConstantInstruction(ConstantDesc constantValue)

Nested and Inner Type Summary

Modifier and Type	Class and Description
public static interface	ConstantInstruction.ArgumentConstantInstruction Models an "argument constant" instruction, which encodes the constant value in the instruction directly.
public static interface	ConstantInstruction.IntrinsicConstantInstruction Models an "intrinsic constant" instruction, which encodes the constant value in its opcode.
public static interface	ConstantInstruction.LoadConstantInstruction Models a "load constant" instruction, which encodes the constant value in the constant pool.

Method Summary

Modifier and Type	Method and Description
public ConstantDesc	Returns: the constant value constantValue() Returns the constant value.
public static ConstantInstruction.ArgumentConstantInstruction	Returns: an argument constant instruction ofArgument(Opcode the opcode for the specific type of argument constant instruction, which must be `Opcode#BIPUSH` or `Opcode#SIPUSH` op, int the constant value value) Returns an argument constant instruction.
public static ConstantInstruction.IntrinsicConstantInstruction	Returns: an intrinsic constant instruction ofIntrinsic(Opcode the opcode for the specific type of intrinsic constant instruction, which must be of kind `Opcode.Kind#CONSTANT` op) Returns an intrinsic constant instruction.
public static ConstantInstruction.LoadConstantInstruction	Returns: a load constant instruction ofLoad(Opcode the opcode for the specific type of load constant instruction, which must be of kind `Opcode.Kind#CONSTANT` op, LoadableConstantEntry the constant value constant) Returns a load constant instruction.
public TypeKind	Returns: the computational type of the constant typeKind() Returns the computational type of the constant.

Inherited from java.lang.classfile.Instruction:: opcode sizeInBytes

Method Detail

constantValue	back to summary
public ConstantDesc constantValue() Returns the constant value. Returns:ConstantDesc the constant value

constantValue

back to summary

public ConstantDesc constantValue()

Returns the constant value.

Returns:ConstantDesc: the constant value

ofArgument back to summary

ofArgument	back to summary
public static ConstantInstruction.ArgumentConstantInstruction ofArgument(Opcode op, int value) Returns an argument constant instruction. `value` must be in the range of `byte`, `[-128, 127]`, for `Opcode#BIPUSH`, and in the range of `short`, `[-32768, 32767]`, for `Opcode#SIPUSH`. Parameters op:Opcode the opcode for the specific type of argument constant instruction, which must be `Opcode#BIPUSH` or `Opcode#SIPUSH` value:int the constant value Returns:ConstantInstruction.ArgumentConstantInstruction an argument constant instruction Exceptions IllegalArgumentException: if the opcode is not `Opcode#BIPUSH` or `Opcode#SIPUSH`, or if the constant value is out of range for the opcode

public static ConstantInstruction.ArgumentConstantInstruction ofArgument(Opcode op, int value)

Returns an argument constant instruction.

value must be in the range of byte, [-128, 127], for Opcode#BIPUSH, and in the range of short, [-32768, 32767], for Opcode#SIPUSH.

Parameters

op:Opcode: the opcode for the specific type of argument constant instruction, which must be Opcode#BIPUSH or Opcode#SIPUSH
value:int: the constant value

Returns:ConstantInstruction.ArgumentConstantInstruction

an argument constant instruction

Exceptions

IllegalArgumentException:: if the opcode is not Opcode#BIPUSH or Opcode#SIPUSH, or if the constant value is out of range for the opcode

ofIntrinsic back to summary

ofIntrinsic	back to summary
public static ConstantInstruction.IntrinsicConstantInstruction ofIntrinsic(Opcode op) Returns an intrinsic constant instruction. Parameters op:Opcode the opcode for the specific type of intrinsic constant instruction, which must be of kind `Opcode.Kind#CONSTANT` Returns:ConstantInstruction.IntrinsicConstantInstruction an intrinsic constant instruction Exceptions IllegalArgumentException: if the opcode does not represent a constant with implicit value

public static ConstantInstruction.IntrinsicConstantInstruction ofIntrinsic(Opcode op)

Returns an intrinsic constant instruction.

Parameters

op:Opcode: the opcode for the specific type of intrinsic constant instruction, which must be of kind Opcode.Kind#CONSTANT

Returns:ConstantInstruction.IntrinsicConstantInstruction

an intrinsic constant instruction

Exceptions

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

ofLoad back to summary

ofLoad	back to summary
public static ConstantInstruction.LoadConstantInstruction ofLoad(Opcode op, LoadableConstantEntry constant) Returns a load constant instruction. Parameters op:Opcode the opcode for the specific type of load constant instruction, which must be of kind `Opcode.Kind#CONSTANT` constant:LoadableConstantEntry the constant value Returns:ConstantInstruction.LoadConstantInstruction a load constant instruction Exceptions IllegalArgumentException: if the opcode is not `Opcode#LDC`, `Opcode#LDC_W`, or `Opcode#LDC2_W`

public static ConstantInstruction.LoadConstantInstruction ofLoad(Opcode op, LoadableConstantEntry constant)

Returns a load constant instruction.

Parameters

op:Opcode: the opcode for the specific type of load constant instruction, which must be of kind Opcode.Kind#CONSTANT
constant:LoadableConstantEntry: the constant value

Returns:ConstantInstruction.LoadConstantInstruction

a load constant instruction

Exceptions

IllegalArgumentException:: if the opcode is not Opcode#LDC, Opcode#LDC_W, or Opcode#LDC2_W

typeKind back to summary

typeKind	back to summary
public TypeKind typeKind() Returns the computational type of the constant. This is derived from the `constantValue`. Returns:TypeKind the computational type of the constant

public TypeKind typeKind()

Returns the computational type of the constant. This is derived from the constantValue.

Returns:TypeKind: the computational type of the constant

java.lang.classfile.instruction back to summary

public sealed Interface ConstantInstruction.ArgumentConstantInstruction

Known Direct Implementers: jdk.internal.classfile.impl.AbstractInstruction.BoundArgumentConstantInstruction, jdk.internal.classfile.impl.AbstractInstruction.UnboundArgumentConstantInstruction

Models an "argument constant" instruction, which encodes the constant value in the instruction directly. Includes bipush and sipush instructions.

An argument constant instruction is composite:

ArgumentConstantInstruction(
    Opcode opcode,
    int constantValue
)

where:

opcode must be one of bipush or sipush.
constantValue must be in the range of byte, [-128, 127], for bipush, and in the range of short, [-32768, 32767], for sipush.

Since: 24
See Also: Opcode.Kind#CONSTANT, ConstantInstruction::ofArgument, CodeBuilder::loadConstant(int), CodeBuilder::bipush, CodeBuilder::sipush

Method Summary

Modifier and Type	Method and Description
public Integer	constantValue() Redeclares java.lang.classfile.instruction.ConstantInstruction.constantValue. Returns the constant value.
public default TypeKind	typeKind() Implements java.lang.classfile.instruction.ConstantInstruction.typeKind. Returns the computational type of the constant.

Inherited from java.lang.classfile.instruction.ConstantInstruction:: ofArgument ofIntrinsic ofLoad

Method Detail

constantValue	back to summary
public Integer constantValue() Redeclares java.lang.classfile.instruction.ConstantInstruction.constantValue. Doc from java.lang.classfile.instruction.ConstantInstruction.constantValue. Returns the constant value. Annotations @Override

constantValue

back to summary

public Integer constantValue()

Redeclares java.lang.classfile.instruction.ConstantInstruction.constantValue.

Doc from java.lang.classfile.instruction.ConstantInstruction.constantValue.

Returns the constant value.

Annotations

@Override

typeKind back to summary

typeKind	back to summary
public default TypeKind typeKind() Implements java.lang.classfile.instruction.ConstantInstruction.typeKind. Doc from java.lang.classfile.instruction.ConstantInstruction.typeKind. Returns the computational type of the constant. This is derived from the `constantValue`. Annotations @Override

public default TypeKind typeKind()

Implements java.lang.classfile.instruction.ConstantInstruction.typeKind.

Doc from java.lang.classfile.instruction.ConstantInstruction.typeKind.

Returns the computational type of the constant. This is derived from the constantValue.

Annotations

@Override

java.lang.classfile.instruction back to summary

public sealed Interface ConstantInstruction.IntrinsicConstantInstruction

Known Direct Implementers: jdk.internal.classfile.impl.AbstractInstruction.UnboundIntrinsicConstantInstruction

Models an "intrinsic constant" instruction, which encodes the constant value in its opcode. Examples include aconst_null and iconst_0.

An intrinsic constant instruction is composite:

IntrinsicConstantInstruction(Opcode opcode)

where:

opcode: Must be of the constant kind and have a fixed size of 1.

Since: 24
See Also: Opcode.Kind#CONSTANT, ConstantInstruction::ofIntrinsic

Method Summary

Modifier and Type	Method and Description
public default TypeKind	typeKind() Implements java.lang.classfile.instruction.ConstantInstruction.typeKind. Returns the computational type of the constant.

Inherited from java.lang.classfile.instruction.ConstantInstruction:: constantValue ofArgument ofIntrinsic ofLoad

Method Detail

typeKind back to summary

typeKind	back to summary
public default TypeKind typeKind() Implements java.lang.classfile.instruction.ConstantInstruction.typeKind. Doc from java.lang.classfile.instruction.ConstantInstruction.typeKind. Returns the computational type of the constant. This is derived from the `constantValue`. Annotations @Override

public default TypeKind typeKind()

Implements java.lang.classfile.instruction.ConstantInstruction.typeKind.

Doc from java.lang.classfile.instruction.ConstantInstruction.typeKind.

Returns the computational type of the constant. This is derived from the constantValue.

Annotations

@Override

java.lang.classfile.instruction back to summary

public sealed Interface ConstantInstruction.LoadConstantInstruction

Known Direct Implementers: jdk.internal.classfile.impl.AbstractInstruction.BoundLoadConstantInstruction, jdk.internal.classfile.impl.AbstractInstruction.UnboundLoadConstantInstruction

Models a "load constant" instruction, which encodes the constant value in the constant pool. Includes ldc and ldc_w, and ldc2_w instructions.

A load constant instruction is composite:

LoadConstantInstruction(LoadableConstantEntry constantEntry)

A "load constant" instruction can load any constant value supported by other constant-load instructions. However, other instructions are usually more optimized, avoiding extra constant pool entries and being smaller.

Since: 24
See Also: Opcode.Kind#CONSTANT, ConstantInstruction::ofLoad, CodeBuilder::ldc

Method Summary

Modifier and Type	Method and Description
public LoadableConstantEntry	Returns: the constant value constantEntry() Returns the constant value.
public default TypeKind	typeKind() Implements java.lang.classfile.instruction.ConstantInstruction.typeKind. Returns the computational type of the constant.

Inherited from java.lang.classfile.instruction.ConstantInstruction:: constantValue ofArgument ofIntrinsic ofLoad

Method Detail

constantEntry	back to summary
public LoadableConstantEntry constantEntry() Returns the constant value. Returns:LoadableConstantEntry the constant value

constantEntry

back to summary

public LoadableConstantEntry constantEntry()

Returns the constant value.

Returns:LoadableConstantEntry: the constant value

typeKind back to summary

typeKind	back to summary
public default TypeKind typeKind() Implements java.lang.classfile.instruction.ConstantInstruction.typeKind. Doc from java.lang.classfile.instruction.ConstantInstruction.typeKind. Returns the computational type of the constant. This is derived from the `constantValue`. Annotations @Override

public default TypeKind typeKind()

Implements java.lang.classfile.instruction.ConstantInstruction.typeKind.

Doc from java.lang.classfile.instruction.ConstantInstruction.typeKind.

Returns the computational type of the constant. This is derived from the constantValue.

Annotations

@Override