8187982: Update SourceVersion to mention restricted keywords

Reviewed-by: mcimadamore

src/java.compiler/share/classes/javax/lang/model/SourceVersion.java

@@ -216,8 +216,9 @@ public enum SourceVersion {
      * Character#isJavaIdentifierStart(int)} returns {@code true},
      * followed only by characters for which {@link
      * Character#isJavaIdentifierPart(int)} returns {@code true}.
-     * This pattern matches regular identifiers, keywords, and the
-     * literals {@code "true"}, {@code "false"}, and {@code "null"}.
+     * This pattern matches regular identifiers, keywords, restricted
+     * keywords, and the literals {@code "true"}, {@code "false"}, and
+     * {@code "null"}.
      * The method returns {@code false} for all other strings.
      *
      * @param name the string to check
@@ -251,10 +252,13 @@ public enum SourceVersion {
      * qualified name in the latest source version.  Unlike {@link
      * #isIdentifier isIdentifier}, this method returns {@code false}
      * for keywords, boolean literals, and the null literal.
+     * This method returns {@code true} for <i>restricted
+     * keywords</i>.
      *
      * @param name the string to check
      * @return {@code true} if this string is a
      * syntactically valid name, {@code false} otherwise.
+     * @jls 3.9 Keywords
      * @jls 6.2 Names and Identifiers
      */
     public static boolean isName(CharSequence name) {
@@ -266,11 +270,14 @@ public enum SourceVersion {
      * qualified name in the given source version.  Unlike {@link
      * #isIdentifier isIdentifier}, this method returns {@code false}
      * for keywords, boolean literals, and the null literal.
+     * This method returns {@code true} for <i>restricted
+     * keywords</i>.
      *
      * @param name the string to check
      * @param version the version to use
      * @return {@code true} if this string is a
      * syntactically valid name, {@code false} otherwise.
+     * @jls 3.9 Keywords
      * @jls 6.2 Names and Identifiers
      * @since 9
      */
@@ -287,6 +294,8 @@ public enum SourceVersion {
     /**
      * Returns whether or not {@code s} is a keyword, boolean literal,
      * or null literal in the latest source version.
+     * This method returns {@code false} for <i>restricted
+     * keywords</i>.
      *
      * @param s the string to check
      * @return {@code true} if {@code s} is a keyword, or boolean
@@ -302,6 +311,8 @@ public enum SourceVersion {
     /**
      * Returns whether or not {@code s} is a keyword, boolean literal,
      * or null literal in the given source version.
+     * This method returns {@code false} for <i>restricted
+     * keywords</i>.
      *
      * @param s the string to check
      * @param version the version to use

src/java.compiler/share/classes/javax/lang/model/element/ModuleElement.java

@@ -87,7 +87,7 @@ public interface ModuleElement extends Element, QualifiedNameable {
      *
      * @return {@code true} if this is an open module and {@code
      * false} otherwise
-     */ // TODO: add @jls to unnamed module section
+     */
     boolean isOpen();
 
     /**
@@ -96,7 +96,9 @@ public interface ModuleElement extends Element, QualifiedNameable {
      *
      * @return {@code true} if this is an unnamed module and {@code
      * false} otherwise
-     */ // TODO: add @jls to unnamed module section
+     *
+     * @jls 7.7.5 Unnamed Modules
+     */
     boolean isUnnamed();
 
     /**

test/langtools/tools/javac/processing/model/TestSourceVersion.java

@@ -41,6 +41,7 @@ public class TestSourceVersion {
     public static void main(String... args) {
         testLatestSupported();
         testVersionVaryingKeywords();
+        testRestrictedKeywords();
     }
 
     private static void testLatestSupported() {
@@ -74,6 +75,27 @@ public class TestSourceVersion {
         }
     }
 
+    private static void testRestrictedKeywords() {
+        // Restricted keywords are not full keywords
+
+        /*
+         * JLS 3.9
+         * " A further ten character sequences are restricted
+         * keywords: open, module, requires, transitive, exports,
+         * opens, to, uses, provides, and with"
+         */
+        Set<String> restrictedKeywords =
+            Set.of("open", "module", "requires", "transitive", "exports",
+                   "opens", "to", "uses", "provides", "with");
+
+        for(String key : restrictedKeywords) {
+            for(SourceVersion version : SourceVersion.values()) {
+                check(false, isKeyword(key, version), "keyword", version);
+                check(true,  isName(key, version),    "name",    version);
+            }
+        }
+    }
+
     private static void check(boolean result, boolean expected,
                               String message, SourceVersion version) {
         if (result != expected) {