8187443: Forest Consolidation: Move files to unified layout

Reviewed-by: darcy, ihse

src/java.base/share/classes/java/lang/module/ModuleReference.java

@@ -0,0 +1,103 @@
+/*
+ * 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;
+}