1 /*
   2  * Copyright (c) 2014, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package jdk.vm.ci.meta;
  24 
  25 import java.lang.invoke.MethodHandle;
  26 
  27 /**
  28  * Interface to access the internals of the {@link MethodHandle} implementation of the VM. An
  29  * implementation of this interface is usually required to access non-public classes, methods, and
  30  * fields of {@link MethodHandle}, i.e., data that is not standardized by the Java specification.
  31  */
  32 public interface MethodHandleAccessProvider {
  33 
  34     /**
  35      * Identification for methods defined on the class {@link MethodHandle} that are processed by
  36      * the {@link MethodHandleAccessProvider}.
  37      */
  38     enum IntrinsicMethod {
  39         /** The method {@code MethodHandle.invokeBasic}. */
  40         INVOKE_BASIC,
  41         /** The method {@code MethodHandle.linkToStatic}. */
  42         LINK_TO_STATIC,
  43         /** The method {@code MethodHandle.linkToSpecial}. */
  44         LINK_TO_SPECIAL,
  45         /** The method {@code MethodHandle.linkToVirtual}. */
  46         LINK_TO_VIRTUAL,
  47         /** The method {@code MethodHandle.linkToInterface}. */
  48         LINK_TO_INTERFACE
  49     }
  50 
  51     /**
  52      * Returns the method handle method intrinsic identifier for the provided method, or
  53      * {@code null} if the method is not an intrinsic processed by this interface.
  54      *
  55      * @throws NullPointerException if {@code method} is null
  56      */
  57     IntrinsicMethod lookupMethodHandleIntrinsic(ResolvedJavaMethod method);
  58 
  59     /**
  60      * Resolves the invocation target for an invocation of {@link IntrinsicMethod#INVOKE_BASIC
  61      * MethodHandle.invokeBasic} with the given constant receiver {@link MethodHandle}. Returns
  62      * {@code null} if the invocation target is not available at this time.
  63      * <p>
  64      * The first invocations of a method handle can use an interpreter to lookup the actual invoked
  65      * method; frequently executed method handles can use Java bytecode generation to avoid the
  66      * interpreter overhead. If the parameter forceBytecodeGeneration is set to true, the VM should
  67      * try to generate bytecodes before this method returns.
  68      */
  69     ResolvedJavaMethod resolveInvokeBasicTarget(JavaConstant methodHandle, boolean forceBytecodeGeneration);
  70 
  71     /**
  72      * Resolves the invocation target for an invocation of a {@code MethodHandle.linkTo*} method
  73      * with the given constant member name. The member name is the last parameter of the
  74      * {@code linkTo*} method. Returns {@code null} if the invocation target is not available at
  75      * this time.
  76      */
  77     ResolvedJavaMethod resolveLinkToTarget(JavaConstant memberName);
  78 }