## Uses of Class
java.lang.invoke.MethodHandle

- Packages that use MethodHandle
  Package | Description
  --- | ---
  java.lang.invoke | The `java.lang.invoke` package contains dynamic language support provided directly by the Java core class libraries and virtual machine.

- - ### Uses of MethodHandle in java.lang.invoke

    Methods in java.lang.invoke that return MethodHandle
    Modifier and Type | Method and Description
    --- | ---
    `static MethodHandle` | MethodHandles.`arrayElementGetter(Class<?> arrayClass)` Produces a method handle giving read access to elements of an array.
    `static MethodHandle` | MethodHandles.`arrayElementSetter(Class<?> arrayClass)` Produces a method handle giving write access to elements of an array.
    `MethodHandle` | MethodHandle.`asCollector(Class<?> arrayType, int arrayLength)` Makes an array-collecting method handle, which accepts a given number of trailing positional arguments and collects them into an array argument.
    `MethodHandle` | MethodHandle.`asFixedArity()` Makes a fixed arity method handle which is otherwise equivalent to the the current method handle.
    `MethodHandle` | MethodHandle.`asSpreader(Class<?> arrayType, int arrayLength)` Makes an array-spreading method handle, which accepts a trailing array argument and spreads its elements as positional arguments.
    `MethodHandle` | MethodHandle.`asType(MethodType newType)` Produces an adapter method handle which adapts the type of the current method handle to a new type.
    `MethodHandle` | MethodHandle.`asVarargsCollector(Class<?> arrayType)` Makes a variable arity adapter which is able to accept any number of trailing positional arguments and collect them into an array argument.
    `MethodHandle` | MethodHandles.Lookup.`bind(Object receiver, String name, MethodType type)` Produces an early-bound method handle for a non-static method.
    `MethodHandle` | MethodHandle.`bindTo(Object x)` Binds a value `x` to the first argument of a method handle, without invoking it.
    `static MethodHandle` | MethodHandles.`catchException(MethodHandle target, Class<? extends Throwable> exType, MethodHandle handler)` Makes a method handle which adapts a target method handle, by running it inside an exception handler.
    `static MethodHandle` | MethodHandles.`constant(Class<?> type, Object value)` Produces a method handle of the requested return type which returns the given constant value every time it is invoked.
    `static MethodHandle` | MethodHandles.`dropArguments(MethodHandle target, int pos, Class<?>... valueTypes)` Produces a method handle which will discard some dummy arguments before calling some other specified target method handle.
    `static MethodHandle` | MethodHandles.`dropArguments(MethodHandle target, int pos, List<Class<?>> valueTypes)` Produces a method handle which will discard some dummy arguments before calling some other specified target method handle.
    `MethodHandle` | VolatileCallSite.`dynamicInvoker()` Produces a method handle equivalent to an invokedynamic instruction which has been linked to this call site.
    `MethodHandle` | MutableCallSite.`dynamicInvoker()` Produces a method handle equivalent to an invokedynamic instruction which has been linked to this call site.
    `MethodHandle` | ConstantCallSite.`dynamicInvoker()` Returns this call site's permanent target.
    `abstract MethodHandle` | CallSite.`dynamicInvoker()` Produces a method handle equivalent to an invokedynamic instruction which has been linked to this call site.
    `static MethodHandle` | MethodHandles.`exactInvoker(MethodType type)` Produces a special invoker method handle which can be used to invoke any method handle of the given type, as if by `invokeExact`.
    `static MethodHandle` | MethodHandles.`explicitCastArguments(MethodHandle target, MethodType newType)` Produces a method handle which adapts the type of the given method handle to a new type by pairwise argument and return type conversion.
    `static MethodHandle` | MethodHandles.`filterArguments(MethodHandle target, int pos, MethodHandle... filters)` Adapts a target method handle by pre-processing one or more of its arguments, each with its own unary filter function, and then calling the target with each pre-processed argument replaced by the result of its corresponding filter function.
    `static MethodHandle` | MethodHandles.`filterReturnValue(MethodHandle target, MethodHandle filter)` Adapts a target method handle by post-processing its return value (if any) with a filter (another method handle).
    `MethodHandle` | MethodHandles.Lookup.`findConstructor(Class<?> refc, MethodType type)` Produces a method handle which creates an object and initializes it, using the constructor of the specified type.
    `MethodHandle` | MethodHandles.Lookup.`findGetter(Class<?> refc, String name, Class<?> type)` Produces a method handle giving read access to a non-static field.
    `MethodHandle` | MethodHandles.Lookup.`findSetter(Class<?> refc, String name, Class<?> type)` Produces a method handle giving write access to a non-static field.
    `MethodHandle` | MethodHandles.Lookup.`findSpecial(Class<?> refc, String name, MethodType type, Class<?> specialCaller)` Produces an early-bound method handle for a virtual method, as if called from an `invokespecial` instruction from `caller`.
    `MethodHandle` | MethodHandles.Lookup.`findStatic(Class<?> refc, String name, MethodType type)` Produces a method handle for a static method.
    `MethodHandle` | MethodHandles.Lookup.`findStaticGetter(Class<?> refc, String name, Class<?> type)` Produces a method handle giving read access to a static field.
    `MethodHandle` | MethodHandles.Lookup.`findStaticSetter(Class<?> refc, String name, Class<?> type)` Produces a method handle giving write access to a static field.
    `MethodHandle` | MethodHandles.Lookup.`findVirtual(Class<?> refc, String name, MethodType type)` Produces a method handle for a virtual method.
    `static MethodHandle` | MethodHandles.`foldArguments(MethodHandle target, MethodHandle combiner)` Adapts a target method handle by pre-processing some of its arguments, and then calling the target with the result of the pre-processing, inserted into the original sequence of arguments.
    `MethodHandle` | VolatileCallSite.`getTarget()` Returns the target method of the call site, which behaves like a `volatile` field of the `VolatileCallSite`.
    `MethodHandle` | MutableCallSite.`getTarget()` Returns the target method of the call site, which behaves like a normal field of the `MutableCallSite`.
    `MethodHandle` | ConstantCallSite.`getTarget()` Returns the target method of the call site, which behaves like a `final` field of the `ConstantCallSite`.
    `abstract MethodHandle` | CallSite.`getTarget()` Returns the target method of the call site, according to the behavior defined by this call site's specific class.
    `MethodHandle` | SwitchPoint.`guardWithTest(MethodHandle target, MethodHandle fallback)` Returns a method handle which always delegates either to the target or the fallback.
    `static MethodHandle` | MethodHandles.`guardWithTest(MethodHandle test, MethodHandle target, MethodHandle fallback)` Makes a method handle which adapts a target method handle, by guarding it with a test, a boolean-valued method handle.
    `static MethodHandle` | MethodHandles.`identity(Class<?> type)` Produces a method handle which returns its sole argument when invoked.
    `static MethodHandle` | MethodHandles.`insertArguments(MethodHandle target, int pos, Object... values)` Provides a target method handle with one or more bound arguments in advance of the method handle's invocation.
    `static MethodHandle` | MethodHandles.`invoker(MethodType type)` Produces a special invoker method handle which can be used to invoke any method handle compatible with the given type, as if by `invoke`.
    `static MethodHandle` | MethodHandles.`permuteArguments(MethodHandle target, MethodType newType, int... reorder)` Produces a method handle which adapts the calling sequence of the given method handle to a new type, by reordering the arguments.
    `static MethodHandle` | MethodHandles.`spreadInvoker(MethodType type, int leadingArgCount)` Produces a method handle which will invoke any method handle of the given `type`, with a given number of trailing arguments replaced by a single trailing `Object[]` array.
    `static MethodHandle` | MethodHandles.`throwException(Class<?> returnType, Class<? extends Throwable> exType)` Produces a method handle which will throw exceptions of the given `exType`.
    `MethodHandle` | MethodHandles.Lookup.`unreflect(Method m)` Makes a direct method handle to m, if the lookup class has permission.
    `MethodHandle` | MethodHandles.Lookup.`unreflectConstructor(Constructor c)` Produces a method handle for a reflected constructor.
    `MethodHandle` | MethodHandles.Lookup.`unreflectGetter(Field f)` Produces a method handle giving read access to a reflected field.
    `MethodHandle` | MethodHandles.Lookup.`unreflectSetter(Field f)` Produces a method handle giving write access to a reflected field.
    `MethodHandle` | MethodHandles.Lookup.`unreflectSpecial(Method m, Class<?> specialCaller)` Produces a method handle for a reflected method.
    `static MethodHandle` | MethodHandleProxies.`wrapperInstanceTarget(Object x)` Produces or recovers a target method handle which is behaviorally equivalent to the unique method of this wrapper instance.

    Methods in java.lang.invoke with parameters of type MethodHandle
    Modifier and Type | Method and Description
    --- | ---
    `static <T> T` | MethodHandleProxies.`asInterfaceInstance(Class<T> intfc, MethodHandle target)` Produces an instance of the given single-method interface which redirects its calls to the given method handle.
    `static MethodHandle` | MethodHandles.`catchException(MethodHandle target, Class<? extends Throwable> exType, MethodHandle handler)` Makes a method handle which adapts a target method handle, by running it inside an exception handler.
    `static MethodHandle` | MethodHandles.`dropArguments(MethodHandle target, int pos, Class<?>... valueTypes)` Produces a method handle which will discard some dummy arguments before calling some other specified target method handle.
    `static MethodHandle` | MethodHandles.`dropArguments(MethodHandle target, int pos, List<Class<?>> valueTypes)` Produces a method handle which will discard some dummy arguments before calling some other specified target method handle.
    `static MethodHandle` | MethodHandles.`explicitCastArguments(MethodHandle target, MethodType newType)` Produces a method handle which adapts the type of the given method handle to a new type by pairwise argument and return type conversion.
    `static MethodHandle` | MethodHandles.`filterArguments(MethodHandle target, int pos, MethodHandle... filters)` Adapts a target method handle by pre-processing one or more of its arguments, each with its own unary filter function, and then calling the target with each pre-processed argument replaced by the result of its corresponding filter function.
    `static MethodHandle` | MethodHandles.`filterArguments(MethodHandle target, int pos, MethodHandle... filters)` Adapts a target method handle by pre-processing one or more of its arguments, each with its own unary filter function, and then calling the target with each pre-processed argument replaced by the result of its corresponding filter function.
    `static MethodHandle` | MethodHandles.`filterReturnValue(MethodHandle target, MethodHandle filter)` Adapts a target method handle by post-processing its return value (if any) with a filter (another method handle).
    `static MethodHandle` | MethodHandles.`foldArguments(MethodHandle target, MethodHandle combiner)` Adapts a target method handle by pre-processing some of its arguments, and then calling the target with the result of the pre-processing, inserted into the original sequence of arguments.
    `MethodHandle` | SwitchPoint.`guardWithTest(MethodHandle target, MethodHandle fallback)` Returns a method handle which always delegates either to the target or the fallback.
    `static MethodHandle` | MethodHandles.`guardWithTest(MethodHandle test, MethodHandle target, MethodHandle fallback)` Makes a method handle which adapts a target method handle, by guarding it with a test, a boolean-valued method handle.
    `static MethodHandle` | MethodHandles.`insertArguments(MethodHandle target, int pos, Object... values)` Provides a target method handle with one or more bound arguments in advance of the method handle's invocation.
    `static MethodHandle` | MethodHandles.`permuteArguments(MethodHandle target, MethodType newType, int... reorder)` Produces a method handle which adapts the calling sequence of the given method handle to a new type, by reordering the arguments.
    `void` | VolatileCallSite.`setTarget(MethodHandle newTarget)` Updates the target method of this call site, as a volatile variable.
    `void` | MutableCallSite.`setTarget(MethodHandle newTarget)` Updates the target method of this call site, as a normal variable.
    `void` | ConstantCallSite.`setTarget(MethodHandle ignore)` Always throws an `UnsupportedOperationException`.
    `abstract void` | CallSite.`setTarget(MethodHandle newTarget)` Updates the target method of this call site, according to the behavior defined by this call site's specific class.

    Constructors in java.lang.invoke with parameters of type MethodHandle
    Constructor and Description
    `ConstantCallSite(MethodHandle target)` Creates a call site with a permanent target.
    `ConstantCallSite(MethodType targetType, MethodHandle createTargetHook)` Creates a call site with a permanent target, possibly bound to the call site itself.
    `MutableCallSite(MethodHandle target)` Creates a call site object with an initial target method handle.
    `VolatileCallSite(MethodHandle target)` Creates a call site with a volatile binding to its target.

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