| /* |
| * Copyright (c) 2008, 2009, 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 sun.dyn; |
| |
| import java.dyn.MethodHandle; |
| import java.dyn.MethodHandles; |
| import java.dyn.MethodType; |
| |
| |
| /** |
| * Construction and caching of often-used invokers. |
| * @author jrose |
| */ |
| public class Invokers { |
| // exact type (sans leading taget MH) for the outgoing call |
| private final MethodType targetType; |
| |
| // exact invoker for the outgoing call |
| private /*lazy*/ MethodHandle exactInvoker; |
| |
| // generic (untyped) invoker for the outgoing call |
| private /*lazy*/ MethodHandle genericInvoker; |
| |
| // generic (untyped) invoker for the outgoing call; accepts a single Object[] |
| private final /*lazy*/ MethodHandle[] varargsInvokers; |
| |
| /** Compute and cache information common to all collecting adapters |
| * that implement members of the erasure-family of the given erased type. |
| */ |
| public Invokers(Access token, MethodType targetType) { |
| Access.check(token); |
| this.targetType = targetType; |
| this.varargsInvokers = new MethodHandle[targetType.parameterCount()+1]; |
| } |
| |
| public static MethodType invokerType(MethodType targetType) { |
| return targetType.insertParameterTypes(0, MethodHandle.class); |
| } |
| |
| public MethodHandle exactInvoker() { |
| MethodHandle invoker = exactInvoker; |
| if (invoker != null) return invoker; |
| invoker = MethodHandleImpl.IMPL_LOOKUP.findVirtual(MethodHandle.class, "invoke", targetType); |
| if (invoker == null) throw new InternalError("JVM cannot find invoker for "+targetType); |
| assert(invokerType(targetType) == invoker.type()); |
| exactInvoker = invoker; |
| return invoker; |
| } |
| |
| public MethodHandle genericInvoker() { |
| MethodHandle invoker1 = exactInvoker(); |
| MethodHandle invoker = genericInvoker; |
| if (invoker != null) return invoker; |
| MethodType genericType = targetType.generic(); |
| invoker = MethodHandles.convertArguments(invoker1, invokerType(genericType)); |
| genericInvoker = invoker; |
| return invoker; |
| } |
| |
| public MethodHandle varargsInvoker(int objectArgCount) { |
| MethodHandle vaInvoker = varargsInvokers[objectArgCount]; |
| if (vaInvoker != null) return vaInvoker; |
| MethodHandle gInvoker = genericInvoker(); |
| MethodType vaType = MethodType.genericMethodType(objectArgCount, true); |
| vaInvoker = MethodHandles.spreadArguments(gInvoker, invokerType(vaType)); |
| varargsInvokers[objectArgCount] = vaInvoker; |
| return vaInvoker; |
| } |
| |
| public String toString() { |
| return "Invokers"+targetType; |
| } |
| } |