Module io.smallrye.classfile

Package io.smallrye.classfile.attribute

Interface StackMapFrameInfo

public sealed interface StackMapFrameInfo

Models a stack map frame in a StackMapTable attribute (JVMS ). A stack map frame must appear at the beginning of each basic block in a method (JVMS ).

API Note:

In general, a stack map frame should be defined for each target of a BranchInstruction, or unreachable code right after an unconditional branch instruction like goto. The automatic stack map generation cannot handle unreachable code right after an unconditional jump; The ClassFile.DeadCodeOption allows substituting such code, or advanced users can provide their own stack maps for dead code.

Since:

24

See Also:

• StackMapTableAttribute.entries()

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	StackMapFrameInfo.ObjectVerificationTypeInfo	A stack value for an object type.
static enum	StackMapFrameInfo.SimpleVerificationTypeInfo	A simple stack value.
static interface	StackMapFrameInfo.UninitializedVerificationTypeInfo	An uninitialized stack value.
static interface	StackMapFrameInfo.VerificationTypeInfo	The type of a stack or local variable value.

Method Summary

Modifier and Type	Method	Description
int	frameType()	Returns the raw u1 frame_type.
List<StackMapFrameInfo.VerificationTypeInfo>	locals()	Returns the expanded local variable types.
static StackMapFrameInfo	of(Label target, List<StackMapFrameInfo.VerificationTypeInfo> locals, List<StackMapFrameInfo.VerificationTypeInfo> stack)	Returns a new stack map frame.
List<StackMapFrameInfo.VerificationTypeInfo>	stack()	Returns the expanded operand stack types.
Label	target()	Returns the frame target label.

Method Details

frameType

int frameType()

Returns the raw u1 frame_type.

Returns:

the raw u1 frame_type

target

Label target()

Returns the frame target label.

Returns:

the frame target label

locals

List<StackMapFrameInfo.VerificationTypeInfo> locals()

Returns the expanded local variable types.

Returns:

the expanded local variable types

stack

List<StackMapFrameInfo.VerificationTypeInfo> stack()

Returns the expanded operand stack types.

Returns:

the expanded operand stack types

of

static StackMapFrameInfo of(Label target,
 List<StackMapFrameInfo.VerificationTypeInfo> locals,
 List<StackMapFrameInfo.VerificationTypeInfo> stack)

Returns a new stack map frame.

Parameters:

target - the location of the frame

locals - the complete list of frame locals

stack - the complete frame stack

Returns:

a new stack map frame

Throws:

IllegalArgumentException - if the number of types in locals or stack exceeds the limit of u2