| /* |
| * Copyright (c) 2014, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.lang.invoke; |
| |
| import jdk.internal.HotSpotIntrinsicCandidate; |
| import jdk.internal.util.Preconditions; |
| import jdk.internal.vm.annotation.ForceInline; |
| import jdk.internal.vm.annotation.Stable; |
| |
| import java.lang.reflect.Method; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.function.BiFunction; |
| import java.util.function.Function; |
| |
| import static java.lang.invoke.MethodHandleStatics.UNSAFE; |
| import static java.lang.invoke.MethodHandleStatics.newInternalError; |
| |
| /** |
| * A VarHandle is a dynamically strongly typed reference to a variable, or to a |
| * parametrically-defined family of variables, including static fields, |
| * non-static fields, array elements, or components of an off-heap data |
| * structure. Access to such variables is supported under various |
| * <em>access modes</em>, including plain read/write access, volatile |
| * read/write access, and compare-and-swap. |
| * |
| * <p>VarHandles are immutable and have no visible state. VarHandles cannot be |
| * subclassed by the user. |
| * |
| * <p>A VarHandle has: |
| * <ul> |
| * <li>a {@link #varType variable type} T, the type of every variable referenced |
| * by this VarHandle; and |
| * <li>a list of {@link #coordinateTypes coordinate types} |
| * {@code CT1, CT2, ..., CTn}, the types of <em>coordinate expressions</em> that |
| * jointly locate a variable referenced by this VarHandle. |
| * </ul> |
| * Variable and coordinate types may be primitive or reference, and are |
| * represented by {@code Class} objects. The list of coordinate types may be |
| * empty. |
| * |
| * <p>Factory methods that produce or {@link java.lang.invoke.MethodHandles.Lookup |
| * lookup} VarHandle instances document the supported variable type and the list |
| * of coordinate types. |
| * |
| * <p>Each access mode is associated with one <em>access mode method</em>, a |
| * <a href="MethodHandle.html#sigpoly">signature polymorphic</a> method named |
| * for the access mode. When an access mode method is invoked on a VarHandle |
| * instance, the initial arguments to the invocation are coordinate expressions |
| * that indicate in precisely which object the variable is to be accessed. |
| * Trailing arguments to the invocation represent values of importance to the |
| * access mode. For example, the various compare-and-set or compare-and-exchange |
| * access modes require two trailing arguments for the variable's expected value |
| * and new value. |
| * |
| * <p>The arity and types of arguments to the invocation of an access mode |
| * method are not checked statically. Instead, each access mode method |
| * specifies an {@link #accessModeType(AccessMode) access mode type}, |
| * represented as an instance of {@link MethodType}, that serves as a kind of |
| * method signature against which the arguments are checked dynamically. An |
| * access mode type gives formal parameter types in terms of the coordinate |
| * types of a VarHandle instance and the types for values of importance to the |
| * access mode. An access mode type also gives a return type, often in terms of |
| * the variable type of a VarHandle instance. When an access mode method is |
| * invoked on a VarHandle instance, the symbolic type descriptor at the |
| * call site, the run time types of arguments to the invocation, and the run |
| * time type of the return value, must <a href="#invoke">match</a> the types |
| * given in the access mode type. A runtime exception will be thrown if the |
| * match fails. |
| * |
| * For example, the access mode method {@link #compareAndSet} specifies that if |
| * its receiver is a VarHandle instance with coordinate types |
| * {@code CT1, ..., CTn} and variable type {@code T}, then its access mode type |
| * is {@code (CT1 c1, ..., CTn cn, T expectedValue, T newValue)boolean}. |
| * Suppose that a VarHandle instance can access array elements, and that its |
| * coordinate types are {@code String[]} and {@code int} while its variable type |
| * is {@code String}. The access mode type for {@code compareAndSet} on this |
| * VarHandle instance would be |
| * {@code (String[] c1, int c2, String expectedValue, String newValue)boolean}. |
| * Such a VarHandle instance may produced by the |
| * {@link MethodHandles#arrayElementVarHandle(Class) array factory method} and |
| * access array elements as follows: |
| * <pre> {@code |
| * String[] sa = ... |
| * VarHandle avh = MethodHandles.arrayElementVarHandle(String[].class); |
| * boolean r = avh.compareAndSet(sa, 10, "expected", "new"); |
| * }</pre> |
| * |
| * <p>Access modes control atomicity and consistency properties. |
| * <em>Plain</em> read ({@code get}) and write ({@code set}) |
| * accesses are guaranteed to be bitwise atomic only for references |
| * and for primitive values of at most 32 bits, and impose no observable |
| * ordering constraints with respect to threads other than the |
| * executing thread. <em>Opaque</em> operations are bitwise atomic and |
| * coherently ordered with respect to accesses to the same variable. |
| * In addition to obeying Opaque properties, <em>Acquire</em> mode |
| * reads and their subsequent accesses are ordered after matching |
| * <em>Release</em> mode writes and their previous accesses. In |
| * addition to obeying Acquire and Release properties, all |
| * <em>Volatile</em> operations are totally ordered with respect to |
| * each other. |
| * |
| * <p>Access modes are grouped into the following categories: |
| * <ul> |
| * <li>read access modes that get the value of a variable under specified |
| * memory ordering effects. |
| * The set of corresponding access mode methods belonging to this group |
| * consists of the methods |
| * {@link #get get}, |
| * {@link #getVolatile getVolatile}, |
| * {@link #getAcquire getAcquire}, |
| * {@link #getOpaque getOpaque}. |
| * <li>write access modes that set the value of a variable under specified |
| * memory ordering effects. |
| * The set of corresponding access mode methods belonging to this group |
| * consists of the methods |
| * {@link #set set}, |
| * {@link #setVolatile setVolatile}, |
| * {@link #setRelease setRelease}, |
| * {@link #setOpaque setOpaque}. |
| * <li>atomic update access modes that, for example, atomically compare and set |
| * the value of a variable under specified memory ordering effects. |
| * The set of corresponding access mode methods belonging to this group |
| * consists of the methods |
| * {@link #compareAndSet compareAndSet}, |
| * {@link #weakCompareAndSetPlain weakCompareAndSetPlain}, |
| * {@link #weakCompareAndSet weakCompareAndSet}, |
| * {@link #weakCompareAndSetAcquire weakCompareAndSetAcquire}, |
| * {@link #weakCompareAndSetRelease weakCompareAndSetRelease}, |
| * {@link #compareAndExchangeAcquire compareAndExchangeAcquire}, |
| * {@link #compareAndExchange compareAndExchange}, |
| * {@link #compareAndExchangeRelease compareAndExchangeRelease}, |
| * {@link #getAndSet getAndSet}, |
| * {@link #getAndSetAcquire getAndSetAcquire}, |
| * {@link #getAndSetRelease getAndSetRelease}. |
| * <li>numeric atomic update access modes that, for example, atomically get and |
| * set with addition the value of a variable under specified memory ordering |
| * effects. |
| * The set of corresponding access mode methods belonging to this group |
| * consists of the methods |
| * {@link #getAndAdd getAndAdd}, |
| * {@link #getAndAddAcquire getAndAddAcquire}, |
| * {@link #getAndAddRelease getAndAddRelease}, |
| * <li>bitwise atomic update access modes that, for example, atomically get and |
| * bitwise OR the value of a variable under specified memory ordering |
| * effects. |
| * The set of corresponding access mode methods belonging to this group |
| * consists of the methods |
| * {@link #getAndBitwiseOr getAndBitwiseOr}, |
| * {@link #getAndBitwiseOrAcquire getAndBitwiseOrAcquire}, |
| * {@link #getAndBitwiseOrRelease getAndBitwiseOrRelease}, |
| * {@link #getAndBitwiseAnd getAndBitwiseAnd}, |
| * {@link #getAndBitwiseAndAcquire getAndBitwiseAndAcquire}, |
| * {@link #getAndBitwiseAndRelease getAndBitwiseAndRelease}, |
| * {@link #getAndBitwiseXor getAndBitwiseXor}, |
| * {@link #getAndBitwiseXorAcquire getAndBitwiseXorAcquire}, |
| * {@link #getAndBitwiseXorRelease getAndBitwiseXorRelease}. |
| * </ul> |
| * |
| * <p>Factory methods that produce or {@link java.lang.invoke.MethodHandles.Lookup |
| * lookup} VarHandle instances document the set of access modes that are |
| * supported, which may also include documenting restrictions based on the |
| * variable type and whether a variable is read-only. If an access mode is not |
| * supported then the corresponding access mode method will on invocation throw |
| * an {@code UnsupportedOperationException}. Factory methods should document |
| * any additional undeclared exceptions that may be thrown by access mode |
| * methods. |
| * The {@link #get get} access mode is supported for all |
| * VarHandle instances and the corresponding method never throws |
| * {@code UnsupportedOperationException}. |
| * If a VarHandle references a read-only variable (for example a {@code final} |
| * field) then write, atomic update, numeric atomic update, and bitwise atomic |
| * update access modes are not supported and corresponding methods throw |
| * {@code UnsupportedOperationException}. |
| * Read/write access modes (if supported), with the exception of |
| * {@code get} and {@code set}, provide atomic access for |
| * reference types and all primitive types. |
| * Unless stated otherwise in the documentation of a factory method, the access |
| * modes {@code get} and {@code set} (if supported) provide atomic access for |
| * reference types and all primitives types, with the exception of {@code long} |
| * and {@code double} on 32-bit platforms. |
| * |
| * <p>Access modes will override any memory ordering effects specified at |
| * the declaration site of a variable. For example, a VarHandle accessing a |
| * a field using the {@code get} access mode will access the field as |
| * specified <em>by its access mode</em> even if that field is declared |
| * {@code volatile}. When mixed access is performed extreme care should be |
| * taken since the Java Memory Model may permit surprising results. |
| * |
| * <p>In addition to supporting access to variables under various access modes, |
| * a set of static methods, referred to as memory fence methods, is also |
| * provided for fine-grained control of memory ordering. |
| * |
| * The Java Language Specification permits other threads to observe operations |
| * as if they were executed in orders different than are apparent in program |
| * source code, subject to constraints arising, for example, from the use of |
| * locks, {@code volatile} fields or VarHandles. The static methods, |
| * {@link #fullFence fullFence}, {@link #acquireFence acquireFence}, |
| * {@link #releaseFence releaseFence}, {@link #loadLoadFence loadLoadFence} and |
| * {@link #storeStoreFence storeStoreFence}, can also be used to impose |
| * constraints. Their specifications, as is the case for certain access modes, |
| * are phrased in terms of the lack of "reorderings" -- observable ordering |
| * effects that might otherwise occur if the fence was not present. More |
| * precise phrasing of the specification of access mode methods and memory fence |
| * methods may accompany future updates of the Java Language Specification. |
| * |
| * <h1>Compiling invocation of access mode methods</h1> |
| * A Java method call expression naming an access mode method can invoke a |
| * VarHandle from Java source code. From the viewpoint of source code, these |
| * methods can take any arguments and their polymorphic result (if expressed) |
| * can be cast to any return type. Formally this is accomplished by giving the |
| * access mode methods variable arity {@code Object} arguments and |
| * {@code Object} return types (if the return type is polymorphic), but they |
| * have an additional quality called <em>signature polymorphism</em> which |
| * connects this freedom of invocation directly to the JVM execution stack. |
| * <p> |
| * As is usual with virtual methods, source-level calls to access mode methods |
| * compile to an {@code invokevirtual} instruction. More unusually, the |
| * compiler must record the actual argument types, and may not perform method |
| * invocation conversions on the arguments. Instead, it must generate |
| * instructions to push them on the stack according to their own unconverted |
| * types. The VarHandle object itself will be pushed on the stack before the |
| * arguments. The compiler then generates an {@code invokevirtual} instruction |
| * that invokes the access mode method with a symbolic type descriptor which |
| * describes the argument and return types. |
| * <p> |
| * To issue a complete symbolic type descriptor, the compiler must also |
| * determine the return type (if polymorphic). This is based on a cast on the |
| * method invocation expression, if there is one, or else {@code Object} if the |
| * invocation is an expression, or else {@code void} if the invocation is a |
| * statement. The cast may be to a primitive type (but not {@code void}). |
| * <p> |
| * As a corner case, an uncasted {@code null} argument is given a symbolic type |
| * descriptor of {@code java.lang.Void}. The ambiguity with the type |
| * {@code Void} is harmless, since there are no references of type {@code Void} |
| * except the null reference. |
| * |
| * |
| * <h1><a id="invoke">Performing invocation of access mode methods</a></h1> |
| * The first time an {@code invokevirtual} instruction is executed it is linked |
| * by symbolically resolving the names in the instruction and verifying that |
| * the method call is statically legal. This also holds for calls to access mode |
| * methods. In this case, the symbolic type descriptor emitted by the compiler |
| * is checked for correct syntax, and names it contains are resolved. Thus, an |
| * {@code invokevirtual} instruction which invokes an access mode method will |
| * always link, as long as the symbolic type descriptor is syntactically |
| * well-formed and the types exist. |
| * <p> |
| * When the {@code invokevirtual} is executed after linking, the receiving |
| * VarHandle's access mode type is first checked by the JVM to ensure that it |
| * matches the symbolic type descriptor. If the type |
| * match fails, it means that the access mode method which the caller is |
| * invoking is not present on the individual VarHandle being invoked. |
| * |
| * <p> |
| * Invocation of an access mode method behaves as if an invocation of |
| * {@link MethodHandle#invoke}, where the receiving method handle accepts the |
| * VarHandle instance as the leading argument. More specifically, the |
| * following, where {@code {access-mode}} corresponds to the access mode method |
| * name: |
| * <pre> {@code |
| * VarHandle vh = .. |
| * R r = (R) vh.{access-mode}(p1, p2, ..., pN); |
| * }</pre> |
| * behaves as if: |
| * <pre> {@code |
| * VarHandle vh = .. |
| * VarHandle.AccessMode am = VarHandle.AccessMode.valueFromMethodName("{access-mode}"); |
| * MethodHandle mh = MethodHandles.varHandleExactInvoker( |
| * am, |
| * vh.accessModeType(am)); |
| * |
| * R r = (R) mh.invoke(vh, p1, p2, ..., pN) |
| * }</pre> |
| * (modulo access mode methods do not declare throwing of {@code Throwable}). |
| * This is equivalent to: |
| * <pre> {@code |
| * MethodHandle mh = MethodHandles.lookup().findVirtual( |
| * VarHandle.class, |
| * "{access-mode}", |
| * MethodType.methodType(R, p1, p2, ..., pN)); |
| * |
| * R r = (R) mh.invokeExact(vh, p1, p2, ..., pN) |
| * }</pre> |
| * where the desired method type is the symbolic type descriptor and a |
| * {@link MethodHandle#invokeExact} is performed, since before invocation of the |
| * target, the handle will apply reference casts as necessary and box, unbox, or |
| * widen primitive values, as if by {@link MethodHandle#asType asType} (see also |
| * {@link MethodHandles#varHandleInvoker}). |
| * |
| * More concisely, such behaviour is equivalent to: |
| * <pre> {@code |
| * VarHandle vh = .. |
| * VarHandle.AccessMode am = VarHandle.AccessMode.valueFromMethodName("{access-mode}"); |
| * MethodHandle mh = vh.toMethodHandle(am); |
| * |
| * R r = (R) mh.invoke(p1, p2, ..., pN) |
| * }</pre> |
| * Where, in this case, the method handle is bound to the VarHandle instance. |
| * |
| * |
| * <h1>Invocation checking</h1> |
| * In typical programs, VarHandle access mode type matching will usually |
| * succeed. But if a match fails, the JVM will throw a |
| * {@link WrongMethodTypeException}. |
| * <p> |
| * Thus, an access mode type mismatch which might show up as a linkage error |
| * in a statically typed program can show up as a dynamic |
| * {@code WrongMethodTypeException} in a program which uses VarHandles. |
| * <p> |
| * Because access mode types contain "live" {@code Class} objects, method type |
| * matching takes into account both type names and class loaders. |
| * Thus, even if a VarHandle {@code VH} is created in one class loader |
| * {@code L1} and used in another {@code L2}, VarHandle access mode method |
| * calls are type-safe, because the caller's symbolic type descriptor, as |
| * resolved in {@code L2}, is matched against the original callee method's |
| * symbolic type descriptor, as resolved in {@code L1}. The resolution in |
| * {@code L1} happens when {@code VH} is created and its access mode types are |
| * assigned, while the resolution in {@code L2} happens when the |
| * {@code invokevirtual} instruction is linked. |
| * <p> |
| * Apart from type descriptor checks, a VarHandles's capability to |
| * access it's variables is unrestricted. |
| * If a VarHandle is formed on a non-public variable by a class that has access |
| * to that variable, the resulting VarHandle can be used in any place by any |
| * caller who receives a reference to it. |
| * <p> |
| * Unlike with the Core Reflection API, where access is checked every time a |
| * reflective method is invoked, VarHandle access checking is performed |
| * <a href="MethodHandles.Lookup.html#access">when the VarHandle is |
| * created</a>. |
| * Thus, VarHandles to non-public variables, or to variables in non-public |
| * classes, should generally be kept secret. They should not be passed to |
| * untrusted code unless their use from the untrusted code would be harmless. |
| * |
| * |
| * <h1>VarHandle creation</h1> |
| * Java code can create a VarHandle that directly accesses any field that is |
| * accessible to that code. This is done via a reflective, capability-based |
| * API called {@link java.lang.invoke.MethodHandles.Lookup |
| * MethodHandles.Lookup}. |
| * For example, a VarHandle for a non-static field can be obtained |
| * from {@link java.lang.invoke.MethodHandles.Lookup#findVarHandle |
| * Lookup.findVarHandle}. |
| * There is also a conversion method from Core Reflection API objects, |
| * {@link java.lang.invoke.MethodHandles.Lookup#unreflectVarHandle |
| * Lookup.unreflectVarHandle}. |
| * <p> |
| * Access to protected field members is restricted to receivers only of the |
| * accessing class, or one of its subclasses, and the accessing class must in |
| * turn be a subclass (or package sibling) of the protected member's defining |
| * class. If a VarHandle refers to a protected non-static field of a declaring |
| * class outside the current package, the receiver argument will be narrowed to |
| * the type of the accessing class. |
| * |
| * <h1>Interoperation between VarHandles and the Core Reflection API</h1> |
| * Using factory methods in the {@link java.lang.invoke.MethodHandles.Lookup |
| * Lookup} API, any field represented by a Core Reflection API object |
| * can be converted to a behaviorally equivalent VarHandle. |
| * For example, a reflective {@link java.lang.reflect.Field Field} can |
| * be converted to a VarHandle using |
| * {@link java.lang.invoke.MethodHandles.Lookup#unreflectVarHandle |
| * Lookup.unreflectVarHandle}. |
| * The resulting VarHandles generally provide more direct and efficient |
| * access to the underlying fields. |
| * <p> |
| * As a special case, when the Core Reflection API is used to view the |
| * signature polymorphic access mode methods in this class, they appear as |
| * ordinary non-polymorphic methods. Their reflective appearance, as viewed by |
| * {@link java.lang.Class#getDeclaredMethod Class.getDeclaredMethod}, |
| * is unaffected by their special status in this API. |
| * For example, {@link java.lang.reflect.Method#getModifiers |
| * Method.getModifiers} |
| * will report exactly those modifier bits required for any similarly |
| * declared method, including in this case {@code native} and {@code varargs} |
| * bits. |
| * <p> |
| * As with any reflected method, these methods (when reflected) may be invoked |
| * directly via {@link java.lang.reflect.Method#invoke java.lang.reflect.Method.invoke}, |
| * via JNI, or indirectly via |
| * {@link java.lang.invoke.MethodHandles.Lookup#unreflect Lookup.unreflect}. |
| * However, such reflective calls do not result in access mode method |
| * invocations. Such a call, if passed the required argument (a single one, of |
| * type {@code Object[]}), will ignore the argument and will throw an |
| * {@code UnsupportedOperationException}. |
| * <p> |
| * Since {@code invokevirtual} instructions can natively invoke VarHandle |
| * access mode methods under any symbolic type descriptor, this reflective view |
| * conflicts with the normal presentation of these methods via bytecodes. |
| * Thus, these native methods, when reflectively viewed by |
| * {@code Class.getDeclaredMethod}, may be regarded as placeholders only. |
| * <p> |
| * In order to obtain an invoker method for a particular access mode type, |
| * use {@link java.lang.invoke.MethodHandles#varHandleExactInvoker} or |
| * {@link java.lang.invoke.MethodHandles#varHandleInvoker}. The |
| * {@link java.lang.invoke.MethodHandles.Lookup#findVirtual Lookup.findVirtual} |
| * API is also able to return a method handle to call an access mode method for |
| * any specified access mode type and is equivalent in behaviour to |
| * {@link java.lang.invoke.MethodHandles#varHandleInvoker}. |
| * |
| * <h1>Interoperation between VarHandles and Java generics</h1> |
| * A VarHandle can be obtained for a variable, such as a a field, which is |
| * declared with Java generic types. As with the Core Reflection API, the |
| * VarHandle's variable type will be constructed from the erasure of the |
| * source-level type. When a VarHandle access mode method is invoked, the |
| * types |
| * of its arguments or the return value cast type may be generic types or type |
| * instances. If this occurs, the compiler will replace those types by their |
| * erasures when it constructs the symbolic type descriptor for the |
| * {@code invokevirtual} instruction. |
| * |
| * @see MethodHandle |
| * @see MethodHandles |
| * @see MethodType |
| * @since 9 |
| */ |
| public abstract class VarHandle { |
| final VarForm vform; |
| |
| VarHandle(VarForm vform) { |
| this.vform = vform; |
| } |
| |
| RuntimeException unsupported() { |
| return new UnsupportedOperationException(); |
| } |
| |
| // Plain accessors |
| |
| /** |
| * Returns the value of a variable, with memory semantics of reading as |
| * if the variable was declared non-{@code volatile}. Commonly referred to |
| * as plain read access. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code get} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET)} on this VarHandle. |
| * |
| * <p>This access mode is supported by all VarHandle instances and never |
| * throws {@code UnsupportedOperationException}. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the value of the |
| * variable |
| * , statically represented using {@code Object}. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object get(Object... args); |
| |
| /** |
| * Sets the value of a variable to the {@code newValue}, with memory |
| * semantics of setting as if the variable was declared non-{@code volatile} |
| * and non-{@code final}. Commonly referred to as plain write access. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)void} |
| * |
| * <p>The symbolic type descriptor at the call site of {@code set} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.SET)} on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| void set(Object... args); |
| |
| |
| // Volatile accessors |
| |
| /** |
| * Returns the value of a variable, with memory semantics of reading as if |
| * the variable was declared {@code volatile}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getVolatile} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_VOLATILE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the value of the |
| * variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getVolatile(Object... args); |
| |
| /** |
| * Sets the value of a variable to the {@code newValue}, with memory |
| * semantics of setting as if the variable was declared {@code volatile}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)void}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code setVolatile} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.SET_VOLATILE)} on this |
| * VarHandle. |
| * |
| * @apiNote |
| * Ignoring the many semantic differences from C and C++, this method has |
| * memory ordering effects compatible with {@code memory_order_seq_cst}. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| void setVolatile(Object... args); |
| |
| |
| /** |
| * Returns the value of a variable, accessed in program order, but with no |
| * assurance of memory ordering effects with respect to other threads. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getOpaque} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_OPAQUE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the value of the |
| * variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getOpaque(Object... args); |
| |
| /** |
| * Sets the value of a variable to the {@code newValue}, in program order, |
| * but with no assurance of memory ordering effects with respect to other |
| * threads. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)void}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code setOpaque} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.SET_OPAQUE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| void setOpaque(Object... args); |
| |
| |
| // Lazy accessors |
| |
| /** |
| * Returns the value of a variable, and ensures that subsequent loads and |
| * stores are not reordered before this access. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_ACQUIRE)} on this |
| * VarHandle. |
| * |
| * @apiNote |
| * Ignoring the many semantic differences from C and C++, this method has |
| * memory ordering effects compatible with {@code memory_order_acquire} |
| * ordering. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the value of the |
| * variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAcquire(Object... args); |
| |
| /** |
| * Sets the value of a variable to the {@code newValue}, and ensures that |
| * prior loads and stores are not reordered after this access. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)void}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code setRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.SET_RELEASE)} on this |
| * VarHandle. |
| * |
| * @apiNote |
| * Ignoring the many semantic differences from C and C++, this method has |
| * memory ordering effects compatible with {@code memory_order_release} |
| * ordering. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| void setRelease(Object... args); |
| |
| |
| // Compare and set accessors |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #setVolatile} if the variable's current value, |
| * referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)boolean}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * compareAndSet} must match the access mode type that is the result of |
| * calling {@code accessModeType(VarHandle.AccessMode.COMPARE_AND_SET)} on |
| * this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return {@code true} if successful, otherwise {@code false} if the |
| * witness value was not the same as the {@code expectedValue}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| boolean compareAndSet(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #setVolatile} if the variable's current value, |
| * referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * compareAndExchange} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.COMPARE_AND_EXCHANGE)} |
| * on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the witness value, which |
| * will be the same as the {@code expectedValue} if successful |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type is not |
| * compatible with the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type is compatible with the |
| * caller's symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object compareAndExchange(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #set} if the variable's current value, |
| * referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * compareAndExchangeAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.COMPARE_AND_EXCHANGE_ACQUIRE)} on |
| * this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the witness value, which |
| * will be the same as the {@code expectedValue} if successful |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #set(Object...) |
| * @see #getAcquire(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object compareAndExchangeAcquire(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #setRelease} if the variable's current value, |
| * referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * compareAndExchangeRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.COMPARE_AND_EXCHANGE_RELEASE)} |
| * on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the witness value, which |
| * will be the same as the {@code expectedValue} if successful |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setRelease(Object...) |
| * @see #get(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object compareAndExchangeRelease(Object... args); |
| |
| // Weak (spurious failures allowed) |
| |
| /** |
| * Possibly atomically sets the value of a variable to the {@code newValue} |
| * with the semantics of {@link #set} if the variable's current value, |
| * referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>This operation may fail spuriously (typically, due to memory |
| * contention) even if the witness value does match the expected value. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)boolean}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * weakCompareAndSetPlain} must match the access mode type that is the result of |
| * calling {@code accessModeType(VarHandle.AccessMode.WEAK_COMPARE_AND_SET_PLAIN)} |
| * on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return {@code true} if successful, otherwise {@code false} if the |
| * witness value was not the same as the {@code expectedValue} or if this |
| * operation spuriously failed. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #set(Object...) |
| * @see #get(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| boolean weakCompareAndSetPlain(Object... args); |
| |
| /** |
| * Possibly atomically sets the value of a variable to the {@code newValue} |
| * with the memory semantics of {@link #setVolatile} if the variable's |
| * current value, referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>This operation may fail spuriously (typically, due to memory |
| * contention) even if the witness value does match the expected value. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)boolean}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * weakCompareAndSet} must match the access mode type that is the |
| * result of calling {@code accessModeType(VarHandle.AccessMode.WEAK_COMPARE_AND_SET)} |
| * on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return {@code true} if successful, otherwise {@code false} if the |
| * witness value was not the same as the {@code expectedValue} or if this |
| * operation spuriously failed. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| boolean weakCompareAndSet(Object... args); |
| |
| /** |
| * Possibly atomically sets the value of a variable to the {@code newValue} |
| * with the semantics of {@link #set} if the variable's current value, |
| * referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>This operation may fail spuriously (typically, due to memory |
| * contention) even if the witness value does match the expected value. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)boolean}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * weakCompareAndSetAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.WEAK_COMPARE_AND_SET_ACQUIRE)} |
| * on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return {@code true} if successful, otherwise {@code false} if the |
| * witness value was not the same as the {@code expectedValue} or if this |
| * operation spuriously failed. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #set(Object...) |
| * @see #getAcquire(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| boolean weakCompareAndSetAcquire(Object... args); |
| |
| /** |
| * Possibly atomically sets the value of a variable to the {@code newValue} |
| * with the semantics of {@link #setRelease} if the variable's current |
| * value, referred to as the <em>witness value</em>, {@code ==} the |
| * {@code expectedValue}, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>This operation may fail spuriously (typically, due to memory |
| * contention) even if the witness value does match the expected value. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)boolean}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code |
| * weakCompareAndSetRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.WEAK_COMPARE_AND_SET_RELEASE)} |
| * on this VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T expectedValue, T newValue)} |
| * , statically represented using varargs. |
| * @return {@code true} if successful, otherwise {@code false} if the |
| * witness value was not the same as the {@code expectedValue} or if this |
| * operation spuriously failed. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setRelease(Object...) |
| * @see #get(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| boolean weakCompareAndSetRelease(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #setVolatile} and returns the variable's |
| * previous value, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndSet} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_SET)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndSet(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #set} and returns the variable's |
| * previous value, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndSetAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_SET_ACQUIRE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndSetAcquire(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the {@code newValue} with the |
| * memory semantics of {@link #setRelease} and returns the variable's |
| * previous value, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T newValue)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndSetRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_SET_RELEASE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T newValue)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndSetRelease(Object... args); |
| |
| // Primitive adders |
| // Throw UnsupportedOperationException for refs |
| |
| /** |
| * Atomically adds the {@code value} to the current value of a variable with |
| * the memory semantics of {@link #setVolatile}, and returns the variable's |
| * previous value, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T value)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndAdd} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_ADD)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T value)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndAdd(Object... args); |
| |
| /** |
| * Atomically adds the {@code value} to the current value of a variable with |
| * the memory semantics of {@link #set}, and returns the variable's |
| * previous value, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T value)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndAddAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_ADD_ACQUIRE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T value)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndAddAcquire(Object... args); |
| |
| /** |
| * Atomically adds the {@code value} to the current value of a variable with |
| * the memory semantics of {@link #setRelease}, and returns the variable's |
| * previous value, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T value)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndAddRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_ADD_RELEASE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T value)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndAddRelease(Object... args); |
| |
| |
| // Bitwise operations |
| // Throw UnsupportedOperationException for refs |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise OR between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #setVolatile} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical OR is performed instead of a bitwise OR. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseOr} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_OR)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseOr(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise OR between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #set} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical OR is performed instead of a bitwise OR. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseOrAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_OR_ACQUIRE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #set(Object...) |
| * @see #getAcquire(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseOrAcquire(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise OR between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #setRelease} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical OR is performed instead of a bitwise OR. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseOrRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_OR_RELEASE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setRelease(Object...) |
| * @see #get(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseOrRelease(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise AND between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #setVolatile} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical AND is performed instead of a bitwise AND. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseAnd} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_AND)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseAnd(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise AND between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #set} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical AND is performed instead of a bitwise AND. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseAndAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_AND_ACQUIRE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #set(Object...) |
| * @see #getAcquire(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseAndAcquire(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise AND between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #setRelease} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical AND is performed instead of a bitwise AND. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseAndRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_AND_RELEASE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setRelease(Object...) |
| * @see #get(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseAndRelease(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise XOR between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #setVolatile} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #getVolatile}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical XOR is performed instead of a bitwise XOR. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseXor} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_XOR)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setVolatile(Object...) |
| * @see #getVolatile(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseXor(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise XOR between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #set} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #getAcquire}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical XOR is performed instead of a bitwise XOR. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseXorAcquire} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_XOR_ACQUIRE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #set(Object...) |
| * @see #getAcquire(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseXorAcquire(Object... args); |
| |
| /** |
| * Atomically sets the value of a variable to the result of |
| * bitwise XOR between the variable's current value and the {@code mask} |
| * with the memory semantics of {@link #setRelease} and returns the |
| * variable's previous value, as accessed with the memory semantics of |
| * {@link #get}. |
| * |
| * <p>If the variable type is the non-integral {@code boolean} type then a |
| * logical XOR is performed instead of a bitwise XOR. |
| * |
| * <p>The method signature is of the form {@code (CT1 ct1, ..., CTn ctn, T mask)T}. |
| * |
| * <p>The symbolic type descriptor at the call site of {@code getAndBitwiseXorRelease} |
| * must match the access mode type that is the result of calling |
| * {@code accessModeType(VarHandle.AccessMode.GET_AND_BITWISE_XOR_RELEASE)} on this |
| * VarHandle. |
| * |
| * @param args the signature-polymorphic parameter list of the form |
| * {@code (CT1 ct1, ..., CTn ctn, T mask)} |
| * , statically represented using varargs. |
| * @return the signature-polymorphic result that is the previous value of |
| * the variable |
| * , statically represented using {@code Object}. |
| * @throws UnsupportedOperationException if the access mode is unsupported |
| * for this VarHandle. |
| * @throws WrongMethodTypeException if the access mode type does not |
| * match the caller's symbolic type descriptor. |
| * @throws ClassCastException if the access mode type matches the caller's |
| * symbolic type descriptor, but a reference cast fails. |
| * @see #setRelease(Object...) |
| * @see #get(Object...) |
| */ |
| public final native |
| @MethodHandle.PolymorphicSignature |
| @HotSpotIntrinsicCandidate |
| Object getAndBitwiseXorRelease(Object... args); |
| |
| |
| enum AccessType { |
| GET(Object.class), |
| SET(void.class), |
| COMPARE_AND_SWAP(boolean.class), |
| COMPARE_AND_EXCHANGE(Object.class), |
| GET_AND_UPDATE(Object.class); |
| |
| final Class<?> returnType; |
| final boolean isMonomorphicInReturnType; |
| |
| AccessType(Class<?> returnType) { |
| this.returnType = returnType; |
| isMonomorphicInReturnType = returnType != Object.class; |
| } |
| |
| MethodType accessModeType(Class<?> receiver, Class<?> value, |
| Class<?>... intermediate) { |
| Class<?>[] ps; |
| int i; |
| switch (this) { |
| case GET: |
| ps = allocateParameters(0, receiver, intermediate); |
| fillParameters(ps, receiver, intermediate); |
| return MethodType.methodType(value, ps); |
| case SET: |
| ps = allocateParameters(1, receiver, intermediate); |
| i = fillParameters(ps, receiver, intermediate); |
| ps[i] = value; |
| return MethodType.methodType(void.class, ps); |
| case COMPARE_AND_SWAP: |
| ps = allocateParameters(2, receiver, intermediate); |
| i = fillParameters(ps, receiver, intermediate); |
| ps[i++] = value; |
| ps[i] = value; |
| return MethodType.methodType(boolean.class, ps); |
| case COMPARE_AND_EXCHANGE: |
| ps = allocateParameters(2, receiver, intermediate); |
| i = fillParameters(ps, receiver, intermediate); |
| ps[i++] = value; |
| ps[i] = value; |
| return MethodType.methodType(value, ps); |
| case GET_AND_UPDATE: |
| ps = allocateParameters(1, receiver, intermediate); |
| i = fillParameters(ps, receiver, intermediate); |
| ps[i] = value; |
| return MethodType.methodType(value, ps); |
| default: |
| throw new InternalError("Unknown AccessType"); |
| } |
| } |
| |
| private static Class<?>[] allocateParameters(int values, |
| Class<?> receiver, Class<?>... intermediate) { |
| int size = ((receiver != null) ? 1 : 0) + intermediate.length + values; |
| return new Class<?>[size]; |
| } |
| |
| private static int fillParameters(Class<?>[] ps, |
| Class<?> receiver, Class<?>... intermediate) { |
| int i = 0; |
| if (receiver != null) |
| ps[i++] = receiver; |
| for (int j = 0; j < intermediate.length; j++) |
| ps[i++] = intermediate[j]; |
| return i; |
| } |
| } |
| |
| /** |
| * The set of access modes that specify how a variable, referenced by a |
| * VarHandle, is accessed. |
| */ |
| public enum AccessMode { |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#get VarHandle.get} |
| */ |
| GET("get", AccessType.GET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#set VarHandle.set} |
| */ |
| SET("set", AccessType.SET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getVolatile VarHandle.getVolatile} |
| */ |
| GET_VOLATILE("getVolatile", AccessType.GET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#setVolatile VarHandle.setVolatile} |
| */ |
| SET_VOLATILE("setVolatile", AccessType.SET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAcquire VarHandle.getAcquire} |
| */ |
| GET_ACQUIRE("getAcquire", AccessType.GET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#setRelease VarHandle.setRelease} |
| */ |
| SET_RELEASE("setRelease", AccessType.SET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getOpaque VarHandle.getOpaque} |
| */ |
| GET_OPAQUE("getOpaque", AccessType.GET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#setOpaque VarHandle.setOpaque} |
| */ |
| SET_OPAQUE("setOpaque", AccessType.SET), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#compareAndSet VarHandle.compareAndSet} |
| */ |
| COMPARE_AND_SET("compareAndSet", AccessType.COMPARE_AND_SWAP), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#compareAndExchange VarHandle.compareAndExchange} |
| */ |
| COMPARE_AND_EXCHANGE("compareAndExchange", AccessType.COMPARE_AND_EXCHANGE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#compareAndExchangeAcquire VarHandle.compareAndExchangeAcquire} |
| */ |
| COMPARE_AND_EXCHANGE_ACQUIRE("compareAndExchangeAcquire", AccessType.COMPARE_AND_EXCHANGE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#compareAndExchangeRelease VarHandle.compareAndExchangeRelease} |
| */ |
| COMPARE_AND_EXCHANGE_RELEASE("compareAndExchangeRelease", AccessType.COMPARE_AND_EXCHANGE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#weakCompareAndSetPlain VarHandle.weakCompareAndSetPlain} |
| */ |
| WEAK_COMPARE_AND_SET_PLAIN("weakCompareAndSetPlain", AccessType.COMPARE_AND_SWAP), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#weakCompareAndSet VarHandle.weakCompareAndSet} |
| */ |
| WEAK_COMPARE_AND_SET("weakCompareAndSet", AccessType.COMPARE_AND_SWAP), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#weakCompareAndSetAcquire VarHandle.weakCompareAndSetAcquire} |
| */ |
| WEAK_COMPARE_AND_SET_ACQUIRE("weakCompareAndSetAcquire", AccessType.COMPARE_AND_SWAP), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#weakCompareAndSetRelease VarHandle.weakCompareAndSetRelease} |
| */ |
| WEAK_COMPARE_AND_SET_RELEASE("weakCompareAndSetRelease", AccessType.COMPARE_AND_SWAP), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndSet VarHandle.getAndSet} |
| */ |
| GET_AND_SET("getAndSet", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndSetAcquire VarHandle.getAndSetAcquire} |
| */ |
| GET_AND_SET_ACQUIRE("getAndSetAcquire", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndSetRelease VarHandle.getAndSetRelease} |
| */ |
| GET_AND_SET_RELEASE("getAndSetRelease", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndAdd VarHandle.getAndAdd} |
| */ |
| GET_AND_ADD("getAndAdd", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndAddAcquire VarHandle.getAndAddAcquire} |
| */ |
| GET_AND_ADD_ACQUIRE("getAndAddAcquire", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndAddRelease VarHandle.getAndAddRelease} |
| */ |
| GET_AND_ADD_RELEASE("getAndAddRelease", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseOr VarHandle.getAndBitwiseOr} |
| */ |
| GET_AND_BITWISE_OR("getAndBitwiseOr", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseOrRelease VarHandle.getAndBitwiseOrRelease} |
| */ |
| GET_AND_BITWISE_OR_RELEASE("getAndBitwiseOrRelease", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseOrAcquire VarHandle.getAndBitwiseOrAcquire} |
| */ |
| GET_AND_BITWISE_OR_ACQUIRE("getAndBitwiseOrAcquire", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseAnd VarHandle.getAndBitwiseAnd} |
| */ |
| GET_AND_BITWISE_AND("getAndBitwiseAnd", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseAndRelease VarHandle.getAndBitwiseAndRelease} |
| */ |
| GET_AND_BITWISE_AND_RELEASE("getAndBitwiseAndRelease", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseAndAcquire VarHandle.getAndBitwiseAndAcquire} |
| */ |
| GET_AND_BITWISE_AND_ACQUIRE("getAndBitwiseAndAcquire", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseXor VarHandle.getAndBitwiseXor} |
| */ |
| GET_AND_BITWISE_XOR("getAndBitwiseXor", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseXorRelease VarHandle.getAndBitwiseXorRelease} |
| */ |
| GET_AND_BITWISE_XOR_RELEASE("getAndBitwiseXorRelease", AccessType.GET_AND_UPDATE), |
| /** |
| * The access mode whose access is specified by the corresponding |
| * method |
| * {@link VarHandle#getAndBitwiseXorAcquire VarHandle.getAndBitwiseXorAcquire} |
| */ |
| GET_AND_BITWISE_XOR_ACQUIRE("getAndBitwiseXorAcquire", AccessType.GET_AND_UPDATE), |
| ; |
| |
| static final Map<String, AccessMode> methodNameToAccessMode; |
| static { |
| // Initial capacity of # values is sufficient to avoid resizes |
| // for the smallest table size (32) |
| methodNameToAccessMode = new HashMap<>(AccessMode.values().length); |
| for (AccessMode am : AccessMode.values()) { |
| methodNameToAccessMode.put(am.methodName, am); |
| } |
| } |
| |
| final String methodName; |
| final AccessType at; |
| |
| AccessMode(final String methodName, AccessType at) { |
| this.methodName = methodName; |
| this.at = at; |
| } |
| |
| /** |
| * Returns the {@code VarHandle} signature-polymorphic method name |
| * associated with this {@code AccessMode} value. |
| * |
| * @return the signature-polymorphic method name |
| * @see #valueFromMethodName |
| */ |
| public String methodName() { |
| return methodName; |
| } |
| |
| /** |
| * Returns the {@code AccessMode} value associated with the specified |
| * {@code VarHandle} signature-polymorphic method name. |
| * |
| * @param methodName the signature-polymorphic method name |
| * @return the {@code AccessMode} value |
| * @throws IllegalArgumentException if there is no {@code AccessMode} |
| * value associated with method name (indicating the method |
| * name does not correspond to a {@code VarHandle} |
| * signature-polymorphic method name). |
| * @see #methodName() |
| */ |
| public static AccessMode valueFromMethodName(String methodName) { |
| AccessMode am = methodNameToAccessMode.get(methodName); |
| if (am != null) return am; |
| throw new IllegalArgumentException("No AccessMode value for method name " + methodName); |
| } |
| |
| @ForceInline |
| static MemberName getMemberName(int ordinal, VarForm vform) { |
| return vform.memberName_table[ordinal]; |
| } |
| } |
| |
| static final class AccessDescriptor { |
| final MethodType symbolicMethodTypeErased; |
| final MethodType symbolicMethodTypeInvoker; |
| final Class<?> returnType; |
| final int type; |
| final int mode; |
| |
| public AccessDescriptor(MethodType symbolicMethodType, int type, int mode) { |
| this.symbolicMethodTypeErased = symbolicMethodType.erase(); |
| this.symbolicMethodTypeInvoker = symbolicMethodType.insertParameterTypes(0, VarHandle.class); |
| this.returnType = symbolicMethodType.returnType(); |
| this.type = type; |
| this.mode = mode; |
| } |
| } |
| |
| /** |
| * Returns the variable type of variables referenced by this VarHandle. |
| * |
| * @return the variable type of variables referenced by this VarHandle |
| */ |
| public final Class<?> varType() { |
| MethodType typeSet = accessModeType(AccessMode.SET); |
| return typeSet.parameterType(typeSet.parameterCount() - 1); |
| } |
| |
| /** |
| * Returns the coordinate types for this VarHandle. |
| * |
| * @return the coordinate types for this VarHandle. The returned |
| * list is unmodifiable |
| */ |
| public final List<Class<?>> coordinateTypes() { |
| MethodType typeGet = accessModeType(AccessMode.GET); |
| return typeGet.parameterList(); |
| } |
| |
| /** |
| * Obtains the access mode type for this VarHandle and a given access mode. |
| * |
| * <p>The access mode type's parameter types will consist of a prefix that |
| * is the coordinate types of this VarHandle followed by further |
| * types as defined by the access mode method. |
| * The access mode type's return type is defined by the return type of the |
| * access mode method. |
| * |
| * @param accessMode the access mode, corresponding to the |
| * signature-polymorphic method of the same name |
| * @return the access mode type for the given access mode |
| */ |
| public final MethodType accessModeType(AccessMode accessMode) { |
| TypesAndInvokers tis = getTypesAndInvokers(); |
| MethodType mt = tis.methodType_table[accessMode.at.ordinal()]; |
| if (mt == null) { |
| mt = tis.methodType_table[accessMode.at.ordinal()] = |
| accessModeTypeUncached(accessMode); |
| } |
| return mt; |
| } |
| abstract MethodType accessModeTypeUncached(AccessMode accessMode); |
| |
| /** |
| * Returns {@code true} if the given access mode is supported, otherwise |
| * {@code false}. |
| * |
| * <p>The return of a {@code false} value for a given access mode indicates |
| * that an {@code UnsupportedOperationException} is thrown on invocation |
| * of the corresponding access mode method. |
| * |
| * @param accessMode the access mode, corresponding to the |
| * signature-polymorphic method of the same name |
| * @return {@code true} if the given access mode is supported, otherwise |
| * {@code false}. |
| */ |
| public final boolean isAccessModeSupported(AccessMode accessMode) { |
| return AccessMode.getMemberName(accessMode.ordinal(), vform) != null; |
| } |
| |
| /** |
| * Obtains a method handle bound to this VarHandle and the given access |
| * mode. |
| * |
| * @apiNote This method, for a VarHandle {@code vh} and access mode |
| * {@code {access-mode}}, returns a method handle that is equivalent to |
| * method handle {@code bmh} in the following code (though it may be more |
| * efficient): |
| * <pre>{@code |
| * MethodHandle mh = MethodHandles.varHandleExactInvoker( |
| * vh.accessModeType(VarHandle.AccessMode.{access-mode})); |
| * |
| * MethodHandle bmh = mh.bindTo(vh); |
| * }</pre> |
| * |
| * @param accessMode the access mode, corresponding to the |
| * signature-polymorphic method of the same name |
| * @return a method handle bound to this VarHandle and the given access mode |
| */ |
| public final MethodHandle toMethodHandle(AccessMode accessMode) { |
| MemberName mn = AccessMode.getMemberName(accessMode.ordinal(), vform); |
| if (mn != null) { |
| MethodHandle mh = getMethodHandle(accessMode.ordinal()); |
| return mh.bindTo(this); |
| } |
| else { |
| // Ensure an UnsupportedOperationException is thrown |
| return MethodHandles.varHandleInvoker(accessMode, accessModeType(accessMode)). |
| bindTo(this); |
| } |
| } |
| |
| @Stable |
| TypesAndInvokers typesAndInvokers; |
| |
| static class TypesAndInvokers { |
| final @Stable |
| MethodType[] methodType_table = |
| new MethodType[VarHandle.AccessType.values().length]; |
| |
| final @Stable |
| MethodHandle[] methodHandle_table = |
| new MethodHandle[AccessMode.values().length]; |
| } |
| |
| @ForceInline |
| private final TypesAndInvokers getTypesAndInvokers() { |
| TypesAndInvokers tis = typesAndInvokers; |
| if (tis == null) { |
| tis = typesAndInvokers = new TypesAndInvokers(); |
| } |
| return tis; |
| } |
| |
| @ForceInline |
| final MethodHandle getMethodHandle(int mode) { |
| TypesAndInvokers tis = getTypesAndInvokers(); |
| MethodHandle mh = tis.methodHandle_table[mode]; |
| if (mh == null) { |
| mh = tis.methodHandle_table[mode] = getMethodHandleUncached(mode); |
| } |
| return mh; |
| } |
| private final MethodHandle getMethodHandleUncached(int mode) { |
| MethodType mt = accessModeType(AccessMode.values()[mode]). |
| insertParameterTypes(0, VarHandle.class); |
| MemberName mn = vform.getMemberName(mode); |
| DirectMethodHandle dmh = DirectMethodHandle.make(mn); |
| // Such a method handle must not be publically exposed directly |
| // otherwise it can be cracked, it must be transformed or rebound |
| // before exposure |
| MethodHandle mh = dmh.copyWith(mt, dmh.form); |
| assert mh.type().erase() == mn.getMethodType().erase(); |
| return mh; |
| } |
| |
| |
| /*non-public*/ |
| final void updateVarForm(VarForm newVForm) { |
| if (vform == newVForm) return; |
| UNSAFE.putObject(this, VFORM_OFFSET, newVForm); |
| UNSAFE.fullFence(); |
| } |
| |
| static final BiFunction<String, List<Integer>, ArrayIndexOutOfBoundsException> |
| AIOOBE_SUPPLIER = Preconditions.outOfBoundsExceptionFormatter( |
| new Function<String, ArrayIndexOutOfBoundsException>() { |
| @Override |
| public ArrayIndexOutOfBoundsException apply(String s) { |
| return new ArrayIndexOutOfBoundsException(s); |
| } |
| }); |
| |
| private static final long VFORM_OFFSET; |
| |
| static { |
| VFORM_OFFSET = UNSAFE.objectFieldOffset(VarHandle.class, "vform"); |
| |
| // The VarHandleGuards must be initialized to ensure correct |
| // compilation of the guard methods |
| UNSAFE.ensureClassInitialized(VarHandleGuards.class); |
| } |
| |
| |
| // Fence methods |
| |
| /** |
| * Ensures that loads and stores before the fence will not be reordered |
| * with |
| * loads and stores after the fence. |
| * |
| * @apiNote Ignoring the many semantic differences from C and C++, this |
| * method has memory ordering effects compatible with |
| * {@code atomic_thread_fence(memory_order_seq_cst)} |
| */ |
| @ForceInline |
| public static void fullFence() { |
| UNSAFE.fullFence(); |
| } |
| |
| /** |
| * Ensures that loads before the fence will not be reordered with loads and |
| * stores after the fence. |
| * |
| * @apiNote Ignoring the many semantic differences from C and C++, this |
| * method has memory ordering effects compatible with |
| * {@code atomic_thread_fence(memory_order_acquire)} |
| */ |
| @ForceInline |
| public static void acquireFence() { |
| UNSAFE.loadFence(); |
| } |
| |
| /** |
| * Ensures that loads and stores before the fence will not be |
| * reordered with stores after the fence. |
| * |
| * @apiNote Ignoring the many semantic differences from C and C++, this |
| * method has memory ordering effects compatible with |
| * {@code atomic_thread_fence(memory_order_release)} |
| */ |
| @ForceInline |
| public static void releaseFence() { |
| UNSAFE.storeFence(); |
| } |
| |
| /** |
| * Ensures that loads before the fence will not be reordered with |
| * loads after the fence. |
| */ |
| @ForceInline |
| public static void loadLoadFence() { |
| UNSAFE.loadLoadFence(); |
| } |
| |
| /** |
| * Ensures that stores before the fence will not be reordered with |
| * stores after the fence. |
| */ |
| @ForceInline |
| public static void storeStoreFence() { |
| UNSAFE.storeStoreFence(); |
| } |
| } |