jdk/src/share/classes/java/dyn/VolatileCallSite.java
changeset 8823 7cd28219a1e4
parent 8717 f75a1efb1412
parent 8822 8145ab9f5f86
child 8824 0762fa26f813
child 9033 a88f5656f05d
--- a/jdk/src/share/classes/java/dyn/VolatileCallSite.java	Wed Jul 05 17:38:31 2017 +0200
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,111 +0,0 @@
-/*
- * Copyright (c) 2010, 2011, 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.dyn;
-
-import java.util.List;
-
-/**
- * A {@code VolatileCallSite} is a {@link CallSite} whose target acts like a volatile variable.
- * An {@code invokedynamic} instruction linked to a {@code VolatileCallSite} sees updates
- * to its call site target immediately, even if the update occurs in another thread.
- * There may be a performance penalty for such tight coupling between threads.
- * <p>
- * Unlike {@code MutableCallSite}, there is no
- * {@linkplain MutableCallSite#syncAll syncAll operation} on volatile
- * call sites, since every write to a volatile variable is implicitly
- * synchronized with reader threads.
- * <p>
- * In other respects, a {@code VolatileCallSite} is interchangeable
- * with {@code MutableCallSite}.
- * @see MutableCallSite
- * @author John Rose, JSR 292 EG
- */
-public class VolatileCallSite extends CallSite {
-    /**
-     * Creates a call site with a volatile binding to its target.
-     * The initial target is set to a method handle
-     * of the given type which will throw an {@code IllegalStateException} if called.
-     * @param type the method type that this call site will have
-     * @throws NullPointerException if the proposed type is null
-     */
-    public VolatileCallSite(MethodType type) {
-        super(type);
-    }
-
-    /**
-     * Creates a call site with a volatile binding to its target.
-     * The target is set to the given value.
-     * @param target the method handle that will be the initial target of the call site
-     * @throws NullPointerException if the proposed target is null
-     */
-    public VolatileCallSite(MethodHandle target) {
-        super(target);
-    }
-
-    /**
-     * Returns the target method of the call site, which behaves
-     * like a {@code volatile} field of the {@code VolatileCallSite}.
-     * <p>
-     * The interactions of {@code getTarget} with memory are the same
-     * as of a read from a {@code volatile} field.
-     * <p>
-     * In particular, the current thread is required to issue a fresh
-     * read of the target from memory, and must not fail to see
-     * a recent update to the target by another thread.
-     *
-     * @return the linkage state of this call site, a method handle which can change over time
-     * @see #setTarget
-     */
-    @Override public final MethodHandle getTarget() {
-        return getTargetVolatile();
-    }
-
-    /**
-     * Updates the target method of this call site, as a volatile variable.
-     * The type of the new target must agree with the type of the old target.
-     * <p>
-     * The interactions with memory are the same as of a write to a volatile field.
-     * In particular, any threads is guaranteed to see the updated target
-     * the next time it calls {@code getTarget}.
-     * @param newTarget the new target
-     * @throws NullPointerException if the proposed new target is null
-     * @throws WrongMethodTypeException if the proposed new target
-     *         has a method type that differs from the previous target
-     * @see #getTarget
-     */
-    @Override public void setTarget(MethodHandle newTarget) {
-        checkTargetChange(getTargetVolatile(), newTarget);
-        setTargetVolatile(newTarget);
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public final MethodHandle dynamicInvoker() {
-        return makeDynamicInvoker();
-    }
-}