aoqi@0: /*
aoqi@0:  * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.  Oracle designates this
aoqi@0:  * particular file as subject to the "Classpath" exception as provided
aoqi@0:  * by Oracle in the LICENSE file that accompanied this code.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  */
aoqi@0: 
aoqi@0: /*
aoqi@0:  * This file is available under and governed by the GNU General Public
aoqi@0:  * License version 2 only, as published by the Free Software Foundation.
aoqi@0:  * However, the following notice accompanied the original version of this
aoqi@0:  * file, and Oracle licenses the original version of this file under the BSD
aoqi@0:  * license:
aoqi@0:  */
aoqi@0: /*
aoqi@0:    Copyright 2009-2013 Attila Szegedi
aoqi@0: 
aoqi@0:    Licensed under both the Apache License, Version 2.0 (the "Apache License")
aoqi@0:    and the BSD License (the "BSD License"), with licensee being free to
aoqi@0:    choose either of the two at their discretion.
aoqi@0: 
aoqi@0:    You may not use this file except in compliance with either the Apache
aoqi@0:    License or the BSD License.
aoqi@0: 
aoqi@0:    If you choose to use this file in compliance with the Apache License, the
aoqi@0:    following notice applies to you:
aoqi@0: 
aoqi@0:        You may obtain a copy of the Apache License at
aoqi@0: 
aoqi@0:            http://www.apache.org/licenses/LICENSE-2.0
aoqi@0: 
aoqi@0:        Unless required by applicable law or agreed to in writing, software
aoqi@0:        distributed under the License is distributed on an "AS IS" BASIS,
aoqi@0:        WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
aoqi@0:        implied. See the License for the specific language governing
aoqi@0:        permissions and limitations under the License.
aoqi@0: 
aoqi@0:    If you choose to use this file in compliance with the BSD License, the
aoqi@0:    following notice applies to you:
aoqi@0: 
aoqi@0:        Redistribution and use in source and binary forms, with or without
aoqi@0:        modification, are permitted provided that the following conditions are
aoqi@0:        met:
aoqi@0:        * Redistributions of source code must retain the above copyright
aoqi@0:          notice, this list of conditions and the following disclaimer.
aoqi@0:        * Redistributions in binary form must reproduce the above copyright
aoqi@0:          notice, this list of conditions and the following disclaimer in the
aoqi@0:          documentation and/or other materials provided with the distribution.
aoqi@0:        * Neither the name of the copyright holder nor the names of
aoqi@0:          contributors may be used to endorse or promote products derived from
aoqi@0:          this software without specific prior written permission.
aoqi@0: 
aoqi@0:        THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
aoqi@0:        IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
aoqi@0:        TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
aoqi@0:        PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
aoqi@0:        BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
aoqi@0:        CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
aoqi@0:        SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
aoqi@0:        BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
aoqi@0:        WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
aoqi@0:        OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
aoqi@0:        ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
aoqi@0: */
aoqi@0: 
aoqi@0: package jdk.internal.dynalink.support;
aoqi@0: 
aoqi@0: import java.util.LinkedList;
aoqi@0: import java.util.List;
aoqi@0: import java.util.ServiceLoader;
aoqi@0: import jdk.internal.dynalink.DynamicLinkerFactory;
aoqi@0: import jdk.internal.dynalink.linker.GuardingDynamicLinker;
aoqi@0: 
aoqi@0: /**
aoqi@0:  * Provides methods for automatic discovery of all guarding dynamic linkers listed in the
aoqi@0:  * <tt>/META-INF/services/jdk.internal.dynalink.linker.GuardingDynamicLinker</tt> resources of all JAR files for a
aoqi@0:  * particular class loader. Ordinarily, you will not use this class directly, but you will use a
aoqi@0:  * {@link DynamicLinkerFactory} instead.
aoqi@0:  */
aoqi@0: public class AutoDiscovery {
aoqi@0: 
aoqi@0:     private AutoDiscovery() {
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Discovers all guarding dynamic linkers listed in JAR files of the context class loader of the current thread.
aoqi@0:      *
aoqi@0:      * @return a list of available linkers. Can be zero-length list but not null.
aoqi@0:      */
aoqi@0:     public static List<GuardingDynamicLinker> loadLinkers() {
aoqi@0:         return getLinkers(ServiceLoader.load(GuardingDynamicLinker.class));
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * Discovers all guarding dynamic linkers listed in JAR files of the specified class loader.
aoqi@0:      *
aoqi@0:      * @param cl the class loader to use
aoqi@0:      * @return a list of guarding dynamic linkers available through the specified class loader. Can be zero-length list
aoqi@0:      * but not null.
aoqi@0:      */
aoqi@0:     public static List<GuardingDynamicLinker> loadLinkers(ClassLoader cl) {
aoqi@0:         return getLinkers(ServiceLoader.load(GuardingDynamicLinker.class, cl));
aoqi@0:     }
aoqi@0: 
aoqi@0:     /**
aoqi@0:      * I can't believe there's no Collections API for making a List given an Iterator...
aoqi@0:      */
aoqi@0:     private static <T> List<T> getLinkers(ServiceLoader<T> loader) {
aoqi@0:         final List<T> list = new LinkedList<>();
aoqi@0:         for(final T linker: loader) {
aoqi@0:             list.add(linker);
aoqi@0:         }
aoqi@0:         return list;
aoqi@0:     }
aoqi@0: }