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Enum Class ClassFile.DeadCodeOption

java.lang.Object

java.lang.Enum<ClassFile.DeadCodeOption>

java.lang.classfile.ClassFile.DeadCodeOption

All Implemented Interfaces:: Serializable, ClassFile.Option, Comparable<ClassFile.DeadCodeOption>, Constable

Enclosing interface:: ClassFile

public static enum ClassFile.DeadCodeOption extends Enum<ClassFile.DeadCodeOption> implements ClassFile.Option

The option describing whether to patch out unreachable code for stack map generation. The default is PATCH_DEAD_CODE to automatically patch unreachable code and generate a valid stack map entry for the patched code.

The stack map generation process may fail when it encounters unreachable code and KEEP_DEAD_CODE is set. In such cases, users should set ClassFile.StackMapsOption.DROP_STACK_MAPS and provide their own stack maps that passes verification (JVMS 4.10.1).

See Java Virtual Machine Specification:

4.10.1 Verification by Type Checking

Since:

See Also:

Nested Class Summary

Nested classes/interfaces declared in class Enum

Enum.EnumDesc<E>

Enum Constant Summary

Enum Constant	Description
`KEEP_DEAD_CODE`	Keep the unreachable code for the accuracy of the generated `class` file.
`PATCH_DEAD_CODE`	Patch unreachable code with dummy code, and generate valid dummy stack map entries.

Method Summary

Modifier and Type	Method	Description
`static ClassFile.DeadCodeOption`	`valueOf(String name)`	Returns the enum constant of this class with the specified name.
`static ClassFile.DeadCodeOption[]`	`values()`	Returns an array containing the constants of this enum class, in the order they are declared.

Methods declared in class Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods declared in class Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

PATCH_DEAD_CODE

public static final ClassFile.DeadCodeOption PATCH_DEAD_CODE

Patch unreachable code with dummy code, and generate valid dummy stack map entries. This ensures the generated code can pass verification (JVMS 4.10.1).

KEEP_DEAD_CODE

public static final ClassFile.DeadCodeOption KEEP_DEAD_CODE

Keep the unreachable code for the accuracy of the generated


class

file. Users should set ClassFile.StackMapsOption.DROP_STACK_MAPS to prevent stack map generation from running and provide their own StackMapTableAttribute to a CodeBuilder.

Method Details

values

public static ClassFile.DeadCodeOption[] values()

Returns an array containing the constants of this enum class, in the order they are declared.

Returns:: an array containing the constants of this enum class, in the order they are declared

valueOf

public static ClassFile.DeadCodeOption valueOf(String name)

Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)

Parameters:: name - the name of the enum constant to be returned.
Returns:: the enum constant with the specified name
Throws:: IllegalArgumentException - if this enum class has no constant with the specified name; NullPointerException - if the argument is null

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