8306729: Add nominal descriptors of modules and packages to Constants API

Reviewed-by: mchung
2025-08-27 06:45:07 +02:00 · 2023-05-03 06:34:58 +00:00 · 2023-05-03 06:34:58 +00:00 · c8f37564bf
commit c8f37564bf
parent 0b5b6429a0
8 changed files with 467 additions and 0 deletions
--- a/src/java.base/share/classes/java/lang/constant/ModuleDesc.java
+++ b/src/java.base/share/classes/java/lang/constant/ModuleDesc.java
@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2023, 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.constant;
+
+import static java.util.Objects.requireNonNull;
+
+/**
+ * A nominal descriptor for a {@code Module} constant.
+ *
+ * <p>
+ * To create a {@link ModuleDesc} for a module, use the {@link #of(String)}
+ * method.
+ *
+ * @jvms 4.4.11 The CONSTANT_Module_info Structure
+ * @since 21
+ */
+public sealed interface ModuleDesc
+        permits ModuleDescImpl {
+
+    /**
+     * Returns a {@link ModuleDesc} for a module,
+     * given the name of the module.
+     *
+     * @param name the module name
+     * @return a {@link ModuleDesc} describing the desired module
+     * @throws NullPointerException if the argument is {@code null}
+     * @throws IllegalArgumentException if the name string is not in the
+     * correct format
+     * @jvms 4.2.3 Module and Package Names
+     */
+    static ModuleDesc of(String name) {
+        ConstantUtils.validateModuleName(requireNonNull(name));
+        return new ModuleDescImpl(name);
+    }
+
+    /**
+     * Returns the module name of this {@link ModuleDesc}.
+     *
+     * @return the module name
+     */
+    String name();
+
+    /**
+     * Compare the specified object with this descriptor for equality.
+     * Returns {@code true} if and only if the specified object is
+     * also a {@link ModuleDesc} and both describe the same module.
+     *
+     * @param o the other object
+     * @return whether this descriptor is equal to the other object
+     */
+    @Override
+    boolean equals(Object o);
+}