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Interface StoreInstruction

All Superinterfaces:: ClassFileElement, CodeElement, Instruction

public sealed interface StoreInstruction extends Instruction

Models a local variable store instruction in the code array of a Code attribute. Corresponding opcodes have a kind of Opcode.Kind.STORE. Delivered as a CodeElement when traversing the elements of a CodeModel.

A local variable store instruction is composite:

StoreInstruction(
    TypeKind typeKind,
    int slot
)

where TypeKind is computational, and slot is within [0, 65535].

astore series of instructions, or reference type store instructions, can also operate on the returnAddress type from discontinued jump subroutine instructions.

Since:

See Also:

Method Summary

Modifier and Type	Method	Description
`static StoreInstruction`	`of(Opcode op, int slot)`	Returns a local variable store instruction.
`static StoreInstruction`	`of(TypeKind kind, int slot)`	Returns a local variable store instruction.
`int`	`slot()`	Returns the local variable slot to store to.
`TypeKind`	`typeKind()`	Returns the computational type of the value to be stored.

Methods declared in interface Instruction

opcode, sizeInBytes

Method Details

slot

int slot()

Returns the local variable slot to store to. The value is within [0, 65535].

Returns:: the local variable slot to store to

typeKind

TypeKind typeKind()

Returns the computational type of the value to be stored. The reference type store instructions also operate on the returnAddress type, which does not apply to reference type load instructions.

Returns:: the computational type of the value to be stored

of

static StoreInstruction of(TypeKind kind, int slot)

Returns a local variable store instruction. kind is converted to its computational type. slot must be within [0, 65535].

Parameters:: kind - the type of the value to be stored; slot - the local variable slot to store to
Returns:: a local variable store instruction
Throws:: IllegalArgumentException - if kind is void or slot is out of range

of

static StoreInstruction of(Opcode op, int slot)

Returns a local variable store instruction.

The range of slot is restricted by the op and its size:

If op has size 1, slot must be exactly the slot value implied by the opcode.
If op has size 2, slot must be within [0, 255].
If op has size 4, slot must be within [0, 65535].

API Note:: The explicit op argument allows creating wide or regular store instructions when the slot can be encoded with more optimized store instructions.
Parameters:: op - the opcode for the specific type of store instruction, which must be of kind Opcode.Kind.STORE; slot - the local variable slot to store to
Returns:: a local variable store instruction
Throws:: IllegalArgumentException - if the opcode kind is not Opcode.Kind.STORE or slot is out of range

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https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/lang/classfile/instruction/StoreInstruction.html