Interface ConstantInstruction

All Superinterfaces:: ClassFileElement, CodeElement, Instruction

All Known Subinterfaces:: ConstantInstruction.ArgumentConstantInstruction, ConstantInstruction.IntrinsicConstantInstruction, ConstantInstruction.LoadConstantInstruction

public sealed interface ConstantInstruction extends Instruction permits ConstantInstruction.IntrinsicConstantInstruction, ConstantInstruction.ArgumentConstantInstruction, ConstantInstruction.LoadConstantInstruction

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)

Sealed Class Hierarchy Graph:

Since:

See Also:

Nested Class Summary

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

Method Summary

Modifier and Type	Method	Description
`ConstantDesc`	`constantValue()`	Returns the constant value.
`static ConstantInstruction.ArgumentConstantInstruction`	`ofArgument(Opcode op, int value)`	Returns an argument constant instruction.
`static ConstantInstruction.IntrinsicConstantInstruction`	`ofIntrinsic(Opcode op)`	Returns an intrinsic constant instruction.
`static ConstantInstruction.LoadConstantInstruction`	`ofLoad(Opcode op, LoadableConstantEntry constant)`	Returns a load constant instruction.
`TypeKind`	`typeKind()`	Returns the computational type of the constant.

Methods declared in interface Instruction

opcode, sizeInBytes

Modifier and Type	Method	Description
`Opcode`	`opcode()`	Returns the operation of this instruction.
`int`	`sizeInBytes()`	Returns the size in bytes of this instruction.

Method Details

constantValue

ConstantDesc constantValue()

Returns the constant value.

Returns:: the constant value

typeKind

TypeKind typeKind()

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

Returns:: the computational type of the constant

ofIntrinsic

static ConstantInstruction.IntrinsicConstantInstruction ofIntrinsic(Opcode 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
Returns:: an intrinsic constant instruction
Throws:: IllegalArgumentException - if the opcode does not represent a constant with implicit value

ofArgument

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 - the opcode for the specific type of argument constant instruction, which must be Opcode.BIPUSH or Opcode.SIPUSH; value - the constant value
Returns:: an argument constant instruction
Throws:: IllegalArgumentException - if the opcode is not Opcode.BIPUSH or Opcode.SIPUSH, or if the constant value is out of range for the opcode

ofLoad

static ConstantInstruction.LoadConstantInstruction ofLoad(Opcode op, LoadableConstantEntry 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; constant - the constant value
Returns:: a load constant instruction
Throws:: IllegalArgumentException - if the opcode is not Opcode.LDC, Opcode.LDC_W, or Opcode.LDC2_W

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