OpenJDK 27 · jdk.internal.reflect.MethodHandleAccessorFactory

Modifier and Type	Class and Description
pack-priv static class	MethodHandleAccessorFactory.LazyStaticHolder

Modifier and Type	Field and Description
private static final int	MAX_JVM_ARITY
private static final ReflectionFactory	reflectionFactory
pack-priv static final int	SPECIALIZED_PARAM_COUNT
private static final Unsafe	UNSAFE

Access	Constructor and Description
pack-priv	MethodHandleAccessorFactory()

Method Summary

Modifier and Type	Method and Description
private static boolean	constructorInSuperclass(Class<?> decl, Constructor<?> ctor)
pack-priv static void	ensureClassInitialized(Class<?> defc) Ensures the given class is initialized.
private static MethodHandle	findCallerSensitiveAdapter(Method method) Finds the method handle of a caller-sensitive adapter for the given caller-sensitive method.
private static MethodHandle	getDirectMethod(Method method, boolean callerSensitive)
public static boolean	Returns: `true` if this method is signature polymorphic isSignaturePolymorphicMethod(Method the method to check method) Signature-polymorphic methods.
private static MethodHandle	makeConstructorHandle(MethodHandle ctor)
pack-priv static MethodHandle	Returns: transformed dmh to be used as a target in direct method accessors makeSpecializedTarget(MethodHandle DirectMethodHandle dmh, boolean whether given dmh represents static method or not isStatic, boolean whether given dmh represents a method with an additional caller Class parameter hasCallerParameter) Transform the given dmh to a specialized target method handle.
pack-priv static MethodHandle	makeTarget(MethodHandle dmh, boolean isStatic, boolean hasCallerParameter) Transforms the given dmh into a target method handle with the method type `(Object, Object[])Object` or `(Object, Class, Object[])Object`
pack-priv static ConstructorAccessorImpl	newConstructorAccessor(Constructor<?> ctor) Creates a ConstructorAccessor for the given reflected constructor.
pack-priv static FieldAccessorImpl	newFieldAccessor(Field field, boolean isReadOnly) Creates a FieldAccessor for the given reflected field.
pack-priv static MethodAccessorImpl	newMethodAccessor(Method method, boolean callerSensitive) Creates a MethodAccessor for the given reflected method.
pack-priv static ConstructorAccessorImpl	Returns: an accessible constructor newSerializableConstructorAccessor(Class<?> the class to instantiate decl, Constructor<?> the constructor to call ctor) Creates a ConstructorAccessor that is capable of creating instances of the given class and instantiated by the given constructor.
private static int	slotCount(Executable member)
pack-priv static MethodType	specializedMethodType(boolean isStatic, boolean hasCallerParameter, int paramCount)
pack-priv static MethodType	specializedMethodTypeForConstructor(int paramCount)
private static boolean	useNativeAccessor(Executable member)

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

MAX_JVM_ARITY	back to summary
private static final int MAX_JVM_ARITY

reflectionFactory	back to summary
private static final ReflectionFactory reflectionFactory

SPECIALIZED_PARAM_COUNT	back to summary
pack-priv static final int SPECIALIZED_PARAM_COUNT

UNSAFE	back to summary
private static final Unsafe UNSAFE

MethodHandleAccessorFactory	back to summary
pack-priv MethodHandleAccessorFactory()

Method Detail

constructorInSuperclass	back to summary
private static boolean constructorInSuperclass(Class<?> decl, Constructor<?> ctor)

ensureClassInitialized	back to summary
pack-priv static void ensureClassInitialized(Class<?> defc) Ensures the given class is initialized. If this is called from , this method returns but defc's class initialization is not completed.

findCallerSensitiveAdapter back to summary

findCallerSensitiveAdapter	back to summary
private static MethodHandle findCallerSensitiveAdapter(Method method) throws IllegalAccessException Finds the method handle of a caller-sensitive adapter for the given caller-sensitive method. It has the same name as the given method with a trailing caller class parameter. See Also `CallerSensitiveAdapter`

private static MethodHandle findCallerSensitiveAdapter(Method method) throws IllegalAccessException

Finds the method handle of a caller-sensitive adapter for the given caller-sensitive method. It has the same name as the given method with a trailing caller class parameter.

See Also: CallerSensitiveAdapter

getDirectMethod	back to summary
private static MethodHandle getDirectMethod(Method method, boolean callerSensitive) throws IllegalAccessException

isSignaturePolymorphicMethod back to summary

isSignaturePolymorphicMethod	back to summary
public static boolean isSignaturePolymorphicMethod(Method method) Signature-polymorphic methods. Lookup has special rules for these methods, but core reflection must observe them as they are declared, and reflective invocation must invoke the native method stubs that throw UOE. Parameters method:Method the method to check Returns:boolean `true` if this method is signature polymorphic Java Language Specification 15.12.3 Compile-Time Step 3: Is the Chosen Method Appropriate? Java Virtual Machine Specification 2.9.3 Signature Polymorphic Methods

public static boolean isSignaturePolymorphicMethod(Method method)

Signature-polymorphic methods. Lookup has special rules for these methods, but core reflection must observe them as they are declared, and reflective invocation must invoke the native method stubs that throw UOE.

Parameters

method:Method: the method to check

Returns:boolean

true if this method is signature polymorphic

Java Language Specification

15.12.3 Compile-Time Step 3: Is the Chosen Method Appropriate?

Java Virtual Machine Specification

2.9.3 Signature Polymorphic Methods

makeConstructorHandle	back to summary
private static MethodHandle makeConstructorHandle(MethodHandle ctor)

makeSpecializedTarget back to summary

makeSpecializedTarget	back to summary
pack-priv static MethodHandle makeSpecializedTarget(MethodHandle dmh, boolean isStatic, boolean hasCallerParameter) Transform the given dmh to a specialized target method handle. If `hasCallerParameter` parameter is true, transform the method handle of this method type: `(Object, Object[], Class)Object` for the default case. If `hasCallerParameter` parameter is false, transform the method handle of this method type: `(Object, Object[])Object` for the default case. If the number of formal arguments is small, use a method type specialized the number of formal arguments is 0, 1, and 2, for example, the method type of a static method with one argument can be: `(Object)Object` If it's a static method, there is no leading Object parameter. API Note This implementation avoids using MethodHandles::catchException to help cold startup performance since this combination is very costly to setup. Parameters dmh:MethodHandle DirectMethodHandle isStatic:boolean whether given dmh represents static method or not hasCallerParameter:boolean whether given dmh represents a method with an additional caller Class parameter Returns:MethodHandle transformed dmh to be used as a target in direct method accessors

pack-priv static MethodHandle makeSpecializedTarget(MethodHandle dmh, boolean isStatic, boolean hasCallerParameter)

Transform the given dmh to a specialized target method handle. If hasCallerParameter parameter is true, transform the method handle of this method type: (Object, Object[], Class)Object for the default case. If hasCallerParameter parameter is false, transform the method handle of this method type: (Object, Object[])Object for the default case. If the number of formal arguments is small, use a method type specialized the number of formal arguments is 0, 1, and 2, for example, the method type of a static method with one argument can be: (Object)Object If it's a static method, there is no leading Object parameter.

API Note

This implementation avoids using MethodHandles::catchException to help cold startup performance since this combination is very costly to setup.

Parameters

dmh:MethodHandle: DirectMethodHandle
isStatic:boolean: whether given dmh represents static method or not
hasCallerParameter:boolean: whether given dmh represents a method with an additional caller Class parameter

Returns:MethodHandle

transformed dmh to be used as a target in direct method accessors

makeTarget	back to summary
pack-priv static MethodHandle makeTarget(MethodHandle dmh, boolean isStatic, boolean hasCallerParameter) Transforms the given dmh into a target method handle with the method type `(Object, Object[])Object` or `(Object, Class, Object[])Object`

newConstructorAccessor	back to summary
pack-priv static ConstructorAccessorImpl newConstructorAccessor(Constructor<?> ctor) Creates a ConstructorAccessor for the given reflected constructor. If a given constructor is called before the java.lang.invoke initialization, it will use the native VM reflection support. Otherwise, it will use the direct method handle of the given constructor.

newFieldAccessor	back to summary
pack-priv static FieldAccessorImpl newFieldAccessor(Field field, boolean isReadOnly) Creates a FieldAccessor for the given reflected field. Limitation: Field access via core reflection is only supported after java.lang.invoke completes initialization. java.lang.invoke initialization starts soon after System::initPhase1 and method handles are ready for use when initPhase2 begins. During early VM startup (initPhase1), fields can be accessed directly from the VM or through JNI.

newFieldAccessor

back to summary

pack-priv static FieldAccessorImpl newFieldAccessor(Field field, boolean isReadOnly)

Creates a FieldAccessor for the given reflected field. Limitation: Field access via core reflection is only supported after java.lang.invoke completes initialization. java.lang.invoke initialization starts soon after System::initPhase1 and method handles are ready for use when initPhase2 begins. During early VM startup (initPhase1), fields can be accessed directly from the VM or through JNI.

newMethodAccessor back to summary

newMethodAccessor	back to summary
pack-priv static MethodAccessorImpl newMethodAccessor(Method method, boolean callerSensitive) Creates a MethodAccessor for the given reflected method. If the given method is called before the java.lang.invoke initialization or the given method is a native method, it will use the native VM reflection support. If the given method is a caller-sensitive method and the corresponding caller-sensitive adapter with the caller class parameter is present, it will use the method handle of the caller-sensitive adapter. Otherwise, it will use the direct method handle of the given method. See Also `CallerSensitive`, `CallerSensitiveAdapter`

pack-priv static MethodAccessorImpl newMethodAccessor(Method method, boolean callerSensitive)

Creates a MethodAccessor for the given reflected method. If the given method is called before the java.lang.invoke initialization or the given method is a native method, it will use the native VM reflection support. If the given method is a caller-sensitive method and the corresponding caller-sensitive adapter with the caller class parameter is present, it will use the method handle of the caller-sensitive adapter. Otherwise, it will use the direct method handle of the given method.

See Also: CallerSensitive, CallerSensitiveAdapter

newSerializableConstructorAccessor	back to summary
pack-priv static ConstructorAccessorImpl newSerializableConstructorAccessor(Class<?> decl, Constructor<?> ctor) Creates a ConstructorAccessor that is capable of creating instances of the given class and instantiated by the given constructor. Parameters decl:Class<?> the class to instantiate ctor:Constructor<?> the constructor to call Returns:ConstructorAccessorImpl an accessible constructor

newSerializableConstructorAccessor

back to summary

pack-priv static ConstructorAccessorImpl newSerializableConstructorAccessor(Class<?> decl, Constructor<?> ctor)

Creates a ConstructorAccessor that is capable of creating instances of the given class and instantiated by the given constructor.

Parameters

decl:Class<?>: the class to instantiate
ctor:Constructor<?>: the constructor to call

Returns:ConstructorAccessorImpl

an accessible constructor

slotCount	back to summary
private static int slotCount(Executable member)

specializedMethodType	back to summary
pack-priv static MethodType specializedMethodType(boolean isStatic, boolean hasCallerParameter, int paramCount)

specializedMethodTypeForConstructor	back to summary
pack-priv static MethodType specializedMethodTypeForConstructor(int paramCount)

useNativeAccessor	back to summary
private static boolean useNativeAccessor(Executable member)

pack-priv final Class MethodHandleAccessorFactory

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail

pack-priv Class MethodHandleAccessorFactory.LazyStaticHolder

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail