diff -r 2c33418a6d57 -r 83b611b88ac8 jdk/test/java/lang/ModuleLayer/LayerControllerTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/lang/ModuleLayer/LayerControllerTest.java	Fri Apr 07 08:05:54 2017 +0000
@@ -0,0 +1,194 @@
+/*
+ * Copyright (c) 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.
+ *
+ * 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
+ * @library /lib/testlibrary
+ * @build LayerControllerTest ModuleUtils
+ * @run testng LayerControllerTest
+ * @summary Basic tests for java.lang.ModuleLayer.Controller
+ */
+
+import java.lang.module.Configuration;
+import java.lang.module.ModuleDescriptor;
+import java.lang.module.ModuleFinder;
+import java.util.List;
+import java.util.Set;
+
+import org.testng.annotations.Test;
+import static org.testng.Assert.*;
+
+@Test
+public class LayerControllerTest {
+
+    /**
+     * Creates a Controller for a module layer containing modules m1 and m2.
+     * Module m1 contains p1, reads java.base, does not export/open any package
+     * Module m2 contains p2, reads java.base, does not export/open any package
+     */
+    private ModuleLayer.Controller createTestLayer() {
+        ModuleDescriptor descriptor1
+            = ModuleDescriptor.newModule("m1")
+                .packages(Set.of("p1"))
+                .requires("java.base")
+                .build();
+
+        ModuleDescriptor descriptor2
+            = ModuleDescriptor.newModule("m2")
+                .requires("java.base")
+                .packages(Set.of("p2"))
+                .build();
+
+        ModuleFinder finder = ModuleUtils.finderOf(descriptor1, descriptor2);
+        ModuleLayer bootLayer = ModuleLayer.boot();
+
+        Configuration cf = bootLayer.configuration()
+                .resolve(finder, ModuleFinder.of(), Set.of("m1", "m2"));
+
+        ClassLoader scl = ClassLoader.getSystemClassLoader();
+
+        ModuleLayer.Controller controller
+            = ModuleLayer.defineModulesWithOneLoader(cf, List.of(bootLayer), scl);
+
+        ModuleLayer layer = controller.layer();
+
+        assertTrue(layer.modules().size() == 2);
+        assertTrue(layer.findModule("m1").isPresent());
+        assertTrue(layer.findModule("m2").isPresent());
+
+        return controller;
+    }
+
+    /**
+     * Basic test of Controller to update modules m1 and m2 to read and
+     * open packages to each other.
+     */
+    public void testBasic() {
+        ModuleLayer.Controller controller = createTestLayer();
+        ModuleLayer layer = controller.layer();
+        Module m1 = layer.findModule("m1").orElseThrow(RuntimeException::new);
+        Module m2 = layer.findModule("m2").orElseThrow(RuntimeException::new);
+
+        assertFalse(m1.canRead(m2));
+        assertFalse(m1.isExported("p1"));
+        assertFalse(m1.isOpen("p1"));
+        assertFalse(m1.isExported("p1", m2));
+        assertFalse(m1.isOpen("p1", m2));
+
+        assertFalse(m2.canRead(m1));
+        assertFalse(m2.isExported("p2"));
+        assertFalse(m2.isOpen("p2"));
+        assertFalse(m2.isExported("p2", m1));
+        assertFalse(m2.isOpen("p2", m1));
+
+        // update m1 to read m2
+        assertTrue(controller.addReads(m1, m2) == controller);
+        assertTrue(m1.canRead(m2));
+        assertFalse(m2.canRead(m1));
+
+        // update m2 to read m1
+        assertTrue(controller.addReads(m2, m1) == controller);
+        assertTrue(m1.canRead(m2));
+        assertTrue(m1.canRead(m1));
+
+        // update m1 to open p1 to m2
+        assertTrue(controller.addOpens(m1, "p1", m2) == controller);
+        assertTrue(m1.isExported("p1", m2));
+        assertTrue(m1.isOpen("p1", m2));
+        assertFalse(m1.isExported("p1"));
+        assertFalse(m1.isOpen("p1"));
+
+        // update m2 to open p2 to m1
+        assertTrue(controller.addOpens(m2, "p2", m1) == controller);
+        assertTrue(m2.isExported("p2", m1));
+        assertTrue(m2.isOpen("p2", m1));
+        assertFalse(m2.isExported("p2"));
+        assertFalse(m2.isOpen("p2"));
+    }
+
+    /**
+     * Test invalid argument handling
+     */
+    public void testBadArguments() {
+        ModuleLayer.Controller controller = createTestLayer();
+        ModuleLayer layer = controller.layer();
+        Module m1 = layer.findModule("m1").orElseThrow(RuntimeException::new);
+        Module m2 = layer.findModule("m2").orElseThrow(RuntimeException::new);
+        Module base = Object.class.getModule();
+
+        // java.base is not in layer
+        try {
+            controller.addReads(base, m2);
+            assertTrue(false);
+        } catch (IllegalArgumentException expected) { }
+
+        // java.base is not in layer
+        try {
+            controller.addOpens(base, "java.lang", m2);
+            assertTrue(false);
+        } catch (IllegalArgumentException expected) { }
+
+        // m1 does not contain java.lang
+        try {
+            controller.addOpens(m1, "java.lang", m2);
+            assertTrue(false);
+        } catch (IllegalArgumentException expected) { }
+    }
+
+    /**
+     * Test null handling
+     */
+    public void testNulls() {
+        ModuleLayer.Controller controller = createTestLayer();
+        ModuleLayer layer = controller.layer();
+        Module m1 = layer.findModule("m1").orElseThrow(RuntimeException::new);
+        Module m2 = layer.findModule("m2").orElseThrow(RuntimeException::new);
+        assertTrue(m1 != null);
+        assertTrue(m2 != null);
+
+        try {
+            controller.addReads(null, m2);
+            assertTrue(false);
+        } catch (NullPointerException expected) { }
+
+        try {
+            controller.addReads(m1, null);
+            assertTrue(false);
+        } catch (NullPointerException expected) { }
+
+        try {
+            controller.addOpens(null, "p1", m2);
+            assertTrue(false);
+        } catch (NullPointerException expected) { }
+
+        try {
+            controller.addOpens(m1, null, m2);
+            assertTrue(false);
+        } catch (NullPointerException expected) { }
+
+        try {
+            controller.addOpens(m1, "p1", null);
+            assertTrue(false);
+        } catch (NullPointerException expected) { }
+    }
+}