--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.dynalink/share/classes/jdk/dynalink/linker/support/DefaultInternalObjectFilter.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,189 @@
+/*
+ * Copyright (c) 2015, 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.
+ */
+
+/*
+ * This file is available under and governed by the GNU General Public
+ * License version 2 only, as published by the Free Software Foundation.
+ * However, the following notice accompanied the original version of this
+ * file, and Oracle licenses the original version of this file under the BSD
+ * license:
+ */
+/*
+ Copyright 2009-2015 Attila Szegedi
+
+ Licensed under both the Apache License, Version 2.0 (the "Apache License")
+ and the BSD License (the "BSD License"), with licensee being free to
+ choose either of the two at their discretion.
+
+ You may not use this file except in compliance with either the Apache
+ License or the BSD License.
+
+ If you choose to use this file in compliance with the Apache License, the
+ following notice applies to you:
+
+ You may obtain a copy of the Apache License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+ implied. See the License for the specific language governing
+ permissions and limitations under the License.
+
+ If you choose to use this file in compliance with the BSD License, the
+ following notice applies to you:
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are
+ met:
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in the
+ documentation and/or other materials provided with the distribution.
+ * Neither the name of the copyright holder nor the names of
+ contributors may be used to endorse or promote products derived from
+ this software without specific prior written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+ PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
+ BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
+ BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+package jdk.dynalink.linker.support;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import jdk.dynalink.DynamicLinkerFactory;
+import jdk.dynalink.linker.MethodHandleTransformer;
+
+/**
+ * Default implementation for a
+ * {@link DynamicLinkerFactory#setInternalObjectsFilter(MethodHandleTransformer)}
+ * that delegates to a pair of filtering method handles. It takes a method
+ * handle of {@code Object(Object)} type for filtering parameter values and
+ * another one of the same type for filtering return values. It applies them as
+ * parameter and return value filters on method handles passed to its
+ * {@link #transform(MethodHandle)} method, on those parameters and return values
+ * that are declared to have type {@link Object}. Also handles
+ * {@link MethodHandle#isVarargsCollector() method handles that support variable
+ * arity calls} with a last {@code Object[]} parameter. You can broadly think of
+ * the parameter filter as being a wrapping method for exposing internal runtime
+ * objects wrapped into an adapter with some public interface, and the return
+ * value filter as being its inverse unwrapping method.
+ */
+public class DefaultInternalObjectFilter implements MethodHandleTransformer {
+ private static final MethodHandle FILTER_VARARGS = new Lookup(MethodHandles.lookup()).findStatic(
+ DefaultInternalObjectFilter.class, "filterVarArgs", MethodType.methodType(Object[].class, MethodHandle.class, Object[].class));
+
+ private final MethodHandle parameterFilter;
+ private final MethodHandle returnFilter;
+ private final MethodHandle varArgFilter;
+
+ /**
+ * Creates a new filter.
+ * @param parameterFilter the filter for method parameters. Must be of type
+ * {@code Object(Object)}, or {@code null}.
+ * @param returnFilter the filter for return values. Must be of type
+ * {@code Object(Object)}, or {@code null}.
+ * @throws IllegalArgumentException if one or both filters are not of the
+ * expected type.
+ */
+ public DefaultInternalObjectFilter(final MethodHandle parameterFilter, final MethodHandle returnFilter) {
+ this.parameterFilter = checkHandle(parameterFilter, "parameterFilter");
+ this.returnFilter = checkHandle(returnFilter, "returnFilter");
+ this.varArgFilter = parameterFilter == null ? null : FILTER_VARARGS.bindTo(parameterFilter);
+ }
+
+ @Override
+ public MethodHandle transform(final MethodHandle target) {
+ assert target != null;
+ MethodHandle[] filters = null;
+ final MethodType type = target.type();
+ final boolean isVarArg = target.isVarargsCollector();
+ final int paramCount = type.parameterCount();
+ final MethodHandle paramsFiltered;
+ // Filter parameters
+ if (parameterFilter != null) {
+ int firstFilter = -1;
+ // Ignore receiver, start from argument 1
+ for(int i = 1; i < paramCount; ++i) {
+ final Class<?> paramType = type.parameterType(i);
+ final boolean filterVarArg = isVarArg && i == paramCount - 1 && paramType == Object[].class;
+ if (filterVarArg || paramType == Object.class) {
+ if (filters == null) {
+ firstFilter = i;
+ filters = new MethodHandle[paramCount - firstFilter];
+ }
+ filters[i - firstFilter] = filterVarArg ? varArgFilter : parameterFilter;
+ }
+ }
+ paramsFiltered = filters != null ? MethodHandles.filterArguments(target, firstFilter, filters) : target;
+ } else {
+ paramsFiltered = target;
+ }
+ // Filter return value if needed
+ final MethodHandle returnFiltered = returnFilter != null && type.returnType() == Object.class ? MethodHandles.filterReturnValue(paramsFiltered, returnFilter) : paramsFiltered;
+ // Preserve varargs collector state
+ return isVarArg && !returnFiltered.isVarargsCollector() ? returnFiltered.asVarargsCollector(type.parameterType(paramCount - 1)) : returnFiltered;
+
+ }
+
+ private static MethodHandle checkHandle(final MethodHandle handle, final String handleKind) {
+ if (handle != null) {
+ final MethodType objectObjectType = MethodType.methodType(Object.class, Object.class);
+ if (!handle.type().equals(objectObjectType)) {
+ throw new IllegalArgumentException("Method type for " + handleKind + " must be " + objectObjectType);
+ }
+ }
+ return handle;
+ }
+
+ @SuppressWarnings("unused")
+ private static Object[] filterVarArgs(final MethodHandle parameterFilter, final Object[] args) throws Throwable {
+ Object[] newArgs = null;
+ for(int i = 0; i < args.length; ++i) {
+ final Object arg = args[i];
+ final Object newArg = parameterFilter.invokeExact(arg);
+ if (arg != newArg) {
+ if (newArgs == null) {
+ newArgs = args.clone();
+ }
+ newArgs[i] = newArg;
+ }
+ }
+ return newArgs == null ? args : newArgs;
+ }
+}