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Interface FieldInstruction

All Superinterfaces:: ClassFileElement, CodeElement, Instruction

public sealed interface FieldInstruction extends Instruction

Models a field access instruction in the code array of a Code attribute. Corresponding opcodes have a kind of Opcode.Kind.FIELD_ACCESS. Delivered as a CodeElement when traversing the elements of a CodeModel.

A field access instruction is composite:

FieldInstruction(
    Opcode opcode,
    FieldRefEntry field,
)

Since:

See Also:

Method Summary

Modifier and Type	Method	Description
`FieldRefEntry`	`field()`	Returns the `FieldRefEntry` constant described by this instruction.
`default Utf8Entry`	`name()`	Returns the name of the field.
`static FieldInstruction`	`of(Opcode op, ClassEntry owner, NameAndTypeEntry nameAndType)`	Returns a field access instruction.
`static FieldInstruction`	`of(Opcode op, ClassEntry owner, Utf8Entry name, Utf8Entry type)`	Returns a field access instruction.
`static FieldInstruction`	`of(Opcode op, FieldRefEntry field)`	Returns a field access instruction.
`default ClassEntry`	`owner()`	Returns the class holding the field.
`default Utf8Entry`	`type()`	Returns the field descriptor string of the field.
`default ClassDesc`	`typeSymbol()`	Returns a symbolic descriptor for the type of the field.

Methods declared in interface Instruction

opcode, sizeInBytes

Method Details

field

FieldRefEntry field()

Returns the FieldRefEntry constant described by this instruction.

Returns:: the FieldRefEntry constant described by this instruction

owner

default ClassEntry owner()

Returns the class holding the field.

Returns:: the class holding the field

name

default Utf8Entry name()

Returns the name of the field.

Returns:: the name of the field

type

default Utf8Entry type()

Returns the field descriptor string of the field.

API Note:: A symbolic descriptor for the type of the field is available through typeSymbol().
Returns:: the field descriptor string of the field

typeSymbol

default ClassDesc typeSymbol()

Returns a symbolic descriptor for the type of the field.

Returns:: a symbolic descriptor for the type of the field

of

static FieldInstruction of(Opcode op, FieldRefEntry field)

Returns a field access instruction.

Parameters:: op - the opcode for the specific type of field access instruction, which must be of kind Opcode.Kind.FIELD_ACCESS; field - a constant pool entry describing the field
Returns:: a field access instruction
Throws:: IllegalArgumentException - if the opcode kind is not Opcode.Kind.FIELD_ACCESS.

of

static FieldInstruction of(Opcode op, ClassEntry owner, Utf8Entry name, Utf8Entry type)

Returns a field access instruction.

Parameters:: op - the opcode for the specific type of field access instruction, which must be of kind Opcode.Kind.FIELD_ACCESS; owner - the class holding the field; name - the name of the field; type - the field descriptor
Returns:: a field access instruction
Throws:: IllegalArgumentException - if the opcode kind is not Opcode.Kind.FIELD_ACCESS.

of

static FieldInstruction of(Opcode op, ClassEntry owner, NameAndTypeEntry nameAndType)

Returns a field access instruction.

Parameters:: op - the opcode for the specific type of field access instruction, which must be of kind Opcode.Kind.FIELD_ACCESS; owner - the class holding the field; nameAndType - the name and field descriptor of the field
Returns:: a field access instruction
Throws:: IllegalArgumentException - if the opcode kind is not Opcode.Kind.FIELD_ACCESS.

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