src/java.base/share/classes/java/lang/reflect/Module.java

*** 557,567 ****
  
      /**
       * Returns {@code true} if this module exports or opens a package to
       * the given module via its module declaration.
       */
!     private boolean isStaticallyExportedOrOpen(String pn, Module other, boolean open) {
          // package is open to everyone or <other>
          Map<String, Set<Module>> openPackages = this.openPackages;
          if (openPackages != null) {
              Set<Module> targets = openPackages.get(pn);
              if (targets != null) {
--- 557,567 ----
  
      /**
       * Returns {@code true} if this module exports or opens a package to
       * the given module via its module declaration.
       */
!     boolean isStaticallyExportedOrOpen(String pn, Module other, boolean open) {
          // package is open to everyone or <other>
          Map<String, Set<Module>> openPackages = this.openPackages;
          if (openPackages != null) {
              Set<Module> targets = openPackages.get(pn);
              if (targets != null) {
*** 641,650 ****
--- 641,656 ----
       *
       * <p> This method has no effect if the package is already exported (or
       * <em>open</em>) to the given module. It also has no effect if
       * invoked on an {@link ModuleDescriptor#isOpen open} module. </p>
       *
+      * @apiNote As specified in section 5.4.3 of the <cite>The Java&trade;
+      * Virtual Machine Specification </cite>, if an attempt to resolve a
+      * symbolic reference fails because of a linkage error, then subsequent
+      * attempts to resolve the reference always fail with the same error that
+      * was thrown as a result of the initial resolution attempt.
+      *
       * @param  pn
       *         The package name
       * @param  other
       *         The module
       *
*** 654,663 ****
--- 660,670 ----
       *         If {@code pn} is {@code null}, or this is a named module and the
       *         package {@code pn} is not a package in this module
       * @throws IllegalStateException
       *         If this is a named module and the caller is not this module
       *
+      * @jvms 5.4.3 Resolution
       * @see #isExported(String,Module)
       */
      @CallerSensitive
      public Module addExports(String pn, Module other) {
          if (pn == null)
*** 674,685 ****
  
          return this;
      }
  
      /**
!      * If the caller's module is this module then update this module to
!      * <em>open</em> the given package to the given module.
       * Opening a package with this method allows all types in the package,
       * and all their members, not just public types and their public members,
       * to be reflected on by the given module when using APIs that support
       * private access or a way to bypass or suppress default Java language
       * access control checks.
--- 681,692 ----
  
          return this;
      }
  
      /**
!      * If this module has <em>opened</em> a package to at least the caller
!      * module then update this module to open the package to the given module.
       * Opening a package with this method allows all types in the package,
       * and all their members, not just public types and their public members,
       * to be reflected on by the given module when using APIs that support
       * private access or a way to bypass or suppress default Java language
       * access control checks.
*** 697,707 ****
       *
       * @throws IllegalArgumentException
       *         If {@code pn} is {@code null}, or this is a named module and the
       *         package {@code pn} is not a package in this module
       * @throws IllegalStateException
!      *         If this is a named module and the caller is not this module
       *
       * @see #isOpen(String,Module)
       * @see AccessibleObject#setAccessible(boolean)
       * @see java.lang.invoke.MethodHandles#privateLookupIn
       */
--- 704,715 ----
       *
       * @throws IllegalArgumentException
       *         If {@code pn} is {@code null}, or this is a named module and the
       *         package {@code pn} is not a package in this module
       * @throws IllegalStateException
!      *         If this is a named module and this module has not opened the
!      *         package to at least the caller
       *
       * @see #isOpen(String,Module)
       * @see AccessibleObject#setAccessible(boolean)
       * @see java.lang.invoke.MethodHandles#privateLookupIn
       */
*** 711,723 ****
              throw new IllegalArgumentException("package is null");
          Objects.requireNonNull(other);
  
          if (isNamed() && !descriptor.isOpen()) {
              Module caller = Reflection.getCallerClass().getModule();
!             if (caller != this) {
!                 throw new IllegalStateException(caller + " != " + this);
!             }
              implAddExportsOrOpens(pn, other, /*open*/true, /*syncVM*/true);
          }
  
          return this;
      }
--- 719,730 ----
              throw new IllegalArgumentException("package is null");
          Objects.requireNonNull(other);
  
          if (isNamed() && !descriptor.isOpen()) {
              Module caller = Reflection.getCallerClass().getModule();
!             if (caller != this && !isOpen(pn, caller))
!                 throw new IllegalStateException(pn + " is not open to " + caller);
              implAddExportsOrOpens(pn, other, /*open*/true, /*syncVM*/true);
          }
  
          return this;
      }
*** 1566,1573 ****
--- 1573,1584 ----
                  }
                  @Override
                  public Stream<Layer> layers(ClassLoader loader) {
                      return Layer.layers(loader);
                  }
+                 @Override
+                 public boolean isStaticallyExported(Module module, String pn, Module other) {
+                     return module.isStaticallyExportedOrOpen(pn, other, false);
+                 }
              });
      }
  }