/*
* Copyright (c) 2008, 2010, 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
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*/
package sun.dyn;
import java.dyn.*;
import sun.dyn.empty.Empty;
/**
* 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;
// erased (partially untyped but with primitives) invoker for the outgoing call
private /*lazy*/ MethodHandle erasedInvoker;
/*lazy*/ MethodHandle erasedInvokerWithDrops; // for InvokeGeneric
// 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;
// invoker for an unbound callsite
private /*lazy*/ MethodHandle uninitializedCallSite;
/** 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;
try {
invoker = MethodHandleImpl.IMPL_LOOKUP.findVirtual(MethodHandle.class, "invoke", targetType);
} catch (NoAccessException ex) {
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 erasedInvoker() {
MethodHandle invoker1 = exactInvoker();
MethodHandle invoker = erasedInvoker;
if (invoker != null) return invoker;
MethodType erasedType = targetType.erase();
if (erasedType == targetType.generic())
invoker = genericInvoker();
else
invoker = MethodHandles.convertArguments(invoker1, invokerType(erasedType));
erasedInvoker = 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;
}
private static MethodHandle THROW_UCS = null;
public MethodHandle uninitializedCallSite() {
MethodHandle invoker = uninitializedCallSite;
if (invoker != null) return invoker;
if (targetType.parameterCount() > 0) {
MethodType type0 = targetType.dropParameterTypes(0, targetType.parameterCount());
Invokers invokers0 = MethodTypeImpl.invokers(Access.TOKEN, type0);
invoker = MethodHandles.dropArguments(invokers0.uninitializedCallSite(),
0, targetType.parameterList());
assert(invoker.type().equals(targetType));
uninitializedCallSite = invoker;
return invoker;
}
if (THROW_UCS == null) {
try {
THROW_UCS = MethodHandleImpl.IMPL_LOOKUP
.findStatic(CallSite.class, "uninitializedCallSite",
MethodType.methodType(Empty.class));
} catch (NoAccessException ex) {
throw new RuntimeException(ex);
}
}
invoker = AdapterMethodHandle.makeRetypeRaw(Access.TOKEN, targetType, THROW_UCS);
assert(invoker.type().equals(targetType));
uninitializedCallSite = invoker;
return invoker;
}
public String toString() {
return "Invokers"+targetType;
}
}