--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/modules/AccessCheck/AccessExportTwice.java	Thu Jan 12 14:04:08 2017 -0500
@@ -0,0 +1,146 @@
+/*
+ * Copyright (c) 2017, 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.
+ *
+ * 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.
+ */
+/*
+ * @test
+ * @summary Class p1.c1 in an unnamed module cannot read p2.c2 in module second_mod,
+ *          even after p2 is exported to all unnamed. Ensures constant
+ *          access check answers when not accessible due to exportedness.
+ * @library /test/lib
+ * @modules java.base/jdk.internal.misc
+ * @modules java.base/jdk.internal.module
+ * @compile myloaders/MySameClassLoader.java
+ * @compile p2/c2.java
+ * @compile p1/c1.java
+ * @run main/othervm AccessExportTwice
+ */
+
+import static jdk.test.lib.Asserts.*;
+
+import java.lang.module.Configuration;
+import java.lang.module.ModuleDescriptor;
+import java.lang.module.ModuleFinder;
+import java.lang.reflect.Layer;
+import java.lang.reflect.Module;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+import myloaders.MySameClassLoader;
+
+//
+// ClassLoader1 --> defines first_mod --> no packages
+//                  defines second_mod --> packages p2
+//
+// first_mod can read second_mod
+// package p2 in second_mod is exported to first_mod
+//
+// class p1.c1 defined in an unnamed module tries to access p2.c2 defined in second_mod
+// Access is not allowed, even after p2 is exported to all unnamed modules.
+
+public class AccessExportTwice {
+
+    // Create a Layer over the boot layer.
+    // Define modules within this layer to test access between
+    // publicly defined classes within packages of those modules.
+    public void createLayerOnBoot() throws Throwable {
+
+        // Define module:     first_mod
+        // Can read:          java.base, second_mod
+        // Packages:          none
+        // Packages exported: none
+        ModuleDescriptor descriptor_first_mod =
+                ModuleDescriptor.module("first_mod")
+                        .requires("java.base")
+                        .requires("second_mod")
+                        .build();
+
+        // Define module:     second_mod
+        // Can read:          java.base
+        // Packages:          p2
+        // Packages exported: p2 is exported to first_mod
+        ModuleDescriptor descriptor_second_mod =
+                ModuleDescriptor.module("second_mod")
+                        .requires("java.base")
+                        .exports("p2", Set.of("first_mod"))
+                        .build();
+
+        // Set up a ModuleFinder containing all modules for this layer
+        ModuleFinder finder = ModuleLibrary.of(descriptor_first_mod, descriptor_second_mod);
+
+        // Resolves "first_mod"
+        Configuration cf = Layer.boot()
+                .configuration()
+                .resolveRequires(finder, ModuleFinder.of(), Set.of("first_mod"));
+
+        // Map each module to the same class loader
+        Map<String, ClassLoader> map = new HashMap<>();
+        map.put("first_mod", MySameClassLoader.loader1);
+        map.put("second_mod", MySameClassLoader.loader1);
+
+        // Create Layer that contains first_mod & second_mod
+        Layer layer = Layer.boot().defineModules(cf, map::get);
+
+        assertTrue(layer.findLoader("first_mod") == MySameClassLoader.loader1);
+        assertTrue(layer.findLoader("second_mod") == MySameClassLoader.loader1);
+        assertTrue(layer.findLoader("java.base") == null);
+
+        Class p2_c2_class = MySameClassLoader.loader1.loadClass("p2.c2");
+        // Use the same loader to load class p1.c1
+        Class p1_c1_class = MySameClassLoader.loader1.loadClass("p1.c1");
+        // First access check for p1.c1
+        try {
+            p1_c1_class.newInstance();
+            throw new RuntimeException("Test Failed, the unnamed module should not have access to public type p2.c2");
+        } catch (IllegalAccessError e) {
+            String message = e.getMessage();
+            if (!(message.contains("cannot access") &&
+                  message.contains("because module second_mod does not export p2 to unnamed module"))) {
+                throw new RuntimeException("Wrong message: " + message);
+            } else {
+                System.out.println("Test Succeeded at attempt #1");
+            }
+        }
+
+        // Export second_mod/p2 to all unnamed modules.
+        Module second_mod = p2_c2_class.getModule();
+        jdk.internal.module.Modules.addExportsToAllUnnamed(second_mod, "p2");
+
+        // Second access check for p1.c1, should have same result as first
+        try {
+            p1_c1_class.newInstance();
+            throw new RuntimeException("Test Failed, access should have been cached above");
+        } catch (IllegalAccessError e) {
+            String message = e.getMessage();
+            if (!(message.contains("cannot access") &&
+                  message.contains("because module second_mod does not export p2 to unnamed module"))) {
+                throw new RuntimeException("Wrong message: " + message);
+            } else {
+                System.out.println("Test Succeeded at attempt #2");
+            }
+        }
+    }
+
+    public static void main(String args[]) throws Throwable {
+      AccessExportTwice test = new AccessExportTwice();
+      test.createLayerOnBoot();
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/modules/AccessCheck/AccessReadTwice.java	Thu Jan 12 14:04:08 2017 -0500
@@ -0,0 +1,154 @@
+/*
+ * Copyright (c) 2017, 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.
+ *
+ * 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.
+ */
+/*
+ * @test
+ * @summary Class p1.c1 in module first_mod cannot read p2.c2 in module second_mod,
+ *          even after a read edge is added between first_mod and second_mod.
+ *          Ensures constant access check answers when not accessible due to readability.
+ * @library /test/lib
+ * @modules java.base/jdk.internal.misc
+ * @modules java.base/jdk.internal.module
+ * @compile p2/c2.java
+ * @compile p1/c1.java
+ * @compile p4/c4.java
+ * @run main/othervm AccessReadTwice
+ */
+
+import static jdk.test.lib.Asserts.*;
+
+import java.lang.module.Configuration;
+import java.lang.module.ModuleDescriptor;
+import java.lang.module.ModuleFinder;
+import java.lang.reflect.Layer;
+import java.lang.reflect.Module;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+//
+// ClassLoader1 --> defines first_mod --> packages p1, p4
+//                  defines second_mod --> package p2
+//
+// package p2 in second_mod is exported to first_mod
+//
+// class p1.c1 defined in first_mod tries to access p2.c2 defined in second_mod
+// Access is not allowed, even after a read edge is added between first_mod and second_mod.
+
+public class AccessReadTwice {
+
+    // Create a Layer over the boot layer.
+    // Define modules within this layer to test access between
+    // publicly defined classes within packages of those modules.
+    public void createLayerOnBoot() throws Throwable {
+
+        // Define module:     first_mod
+        // Can read:          java.base
+        // Packages:          p1, p4
+        // Packages exported: none
+        ModuleDescriptor descriptor_first_mod =
+                ModuleDescriptor.module("first_mod")
+                        .requires("java.base")
+                        .contains(Set.of("p1", "p4"))
+                        .build();
+
+        // Define module:     second_mod
+        // Can read:          java.base
+        // Packages:          p2
+        // Packages exported: p2 is exported to first_mod
+        ModuleDescriptor descriptor_second_mod =
+                ModuleDescriptor.module("second_mod")
+                        .requires("java.base")
+                        .exports("p2", Set.of("first_mod"))
+                        .build();
+
+        // Set up a ModuleFinder containing all modules for this layer
+        ModuleFinder finder = ModuleLibrary.of(descriptor_first_mod, descriptor_second_mod);
+
+        // Resolves "first_mod" and "second_mod"
+        Configuration cf = Layer.boot()
+                .configuration()
+                .resolveRequires(finder, ModuleFinder.of(), Set.of("first_mod", "second_mod"));
+
+        // Map each module to this class loader
+        Map<String, ClassLoader> map = new HashMap<>();
+        ClassLoader loader = AccessReadTwice.class.getClassLoader();
+        map.put("first_mod", loader);
+        map.put("second_mod", loader);
+
+        // Create Layer that contains first_mod & second_mod
+        Layer layer = Layer.boot().defineModules(cf, map::get);
+
+        assertTrue(layer.findLoader("first_mod") == loader);
+        assertTrue(layer.findLoader("second_mod") == loader);
+        assertTrue(layer.findLoader("java.base") == null);
+
+        Class p2_c2_class = loader.loadClass("p2.c2");
+        Class p1_c1_class = loader.loadClass("p1.c1");
+        Class p4_c4_class = loader.loadClass("p4.c4");
+
+        Module first_mod = p1_c1_class.getModule();
+        Module second_mod = p2_c2_class.getModule();
+
+        // Export first_mod/p1 and first_mod/p4 to all unnamed modules so that
+        // this test can use them
+        jdk.internal.module.Modules.addExportsToAllUnnamed(first_mod, "p1");
+        jdk.internal.module.Modules.addExportsToAllUnnamed(first_mod, "p4");
+
+        // First access check for p1.c1
+        try {
+            p1_c1_class.newInstance();
+            throw new RuntimeException("Test Failed, module first_mod should not have access to p2.c2");
+        } catch (IllegalAccessError e) {
+            String message = e.getMessage();
+            if (!(message.contains("cannot access") &&
+                  message.contains("because module first_mod does not read module second_mod"))) {
+                throw new RuntimeException("Wrong message: " + message);
+            } else {
+                System.out.println("Test Succeeded at attempt #1");
+            }
+        }
+
+        // Add a read edge from p4/c4's module (first_mod) to second_mod
+        p4.c4 c4_obj = new p4.c4();
+        c4_obj.addReads(second_mod);
+
+        // Second access check for p1.c1, should have same result as first
+        try {
+            p1_c1_class.newInstance();
+            throw new RuntimeException("Test Failed, access should have been cached above");
+        } catch (IllegalAccessError e) {
+            String message = e.getMessage();
+            if (!(message.contains("cannot access") &&
+                  message.contains("because module first_mod does not read module second_mod"))) {
+                throw new RuntimeException("Wrong message: " + message);
+            } else {
+                System.out.println("Test Succeeded at attempt #2");
+            }
+        }
+    }
+
+    public static void main(String args[]) throws Throwable {
+      AccessReadTwice test = new AccessReadTwice();
+      test.createLayerOnBoot();
+    }
+}

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/modules/AccessCheck/p4/c4.java	Thu Jan 12 14:04:08 2017 -0500
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2017, 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.
+ *
+ * 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.
+ */
+
+// Small class used by multiple hotspot/runtime/modules/AccessCheck/* tests.
+
+package p4;
+
+import java.lang.reflect.Module;
+
+public class c4 {
+    // Add a read edge from c4's module to given module m
+    public void addReads(Module m) {
+        c4.class.getModule().addReads(m);
+    }
+}