| /* |
| * Copyright (c) 2014, 2016, 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 java.lang.module; |
| |
| import java.io.IOException; |
| import java.net.URI; |
| import java.util.Objects; |
| import java.util.Optional; |
| |
| |
| /** |
| * A reference to a module's content. |
| * |
| * <p> A module reference is a concrete implementation of this class that |
| * implements the abstract methods defined by this class. It contains the |
| * module's descriptor and its location, if known. It also has the ability to |
| * create a {@link ModuleReader} in order to access the module's content, which |
| * may be inside the Java run-time system itself or in an artifact such as a |
| * modular JAR file. |
| * |
| * @see ModuleFinder |
| * @see ModuleReader |
| * @since 9 |
| * @spec JPMS |
| */ |
| |
| public abstract class ModuleReference { |
| |
| private final ModuleDescriptor descriptor; |
| private final URI location; |
| |
| /** |
| * Constructs a new instance of this class. |
| * |
| * @param descriptor |
| * The module descriptor |
| * @param location |
| * The module location or {@code null} if not known |
| */ |
| protected ModuleReference(ModuleDescriptor descriptor, URI location) { |
| this.descriptor = Objects.requireNonNull(descriptor); |
| this.location = location; |
| } |
| |
| /** |
| * Returns the module descriptor. |
| * |
| * @return The module descriptor |
| */ |
| public final ModuleDescriptor descriptor() { |
| return descriptor; |
| } |
| |
| /** |
| * Returns the location of this module's content, if known. |
| * |
| * <p> This URI, when present, can be used as the {@linkplain |
| * java.security.CodeSource#getLocation location} value of a {@link |
| * java.security.CodeSource CodeSource} so that a module's classes can be |
| * granted specific permissions when loaded by a {@link |
| * java.security.SecureClassLoader SecureClassLoader}. |
| * |
| * @return The location or an empty {@code Optional} if not known |
| */ |
| public final Optional<URI> location() { |
| return Optional.ofNullable(location); |
| } |
| |
| /** |
| * Opens the module content for reading. |
| * |
| * @return A {@code ModuleReader} to read the module |
| * |
| * @throws IOException |
| * If an I/O error occurs |
| * @throws SecurityException |
| * If denied by the security manager |
| */ |
| public abstract ModuleReader open() throws IOException; |
| } |