--- /dev/null	2019-12-04 18:44:18.020007537 +0000
+++ new/test/jdk/java/foreign/TestSegments.java	2019-12-09 18:15:56.648486580 +0000
@@ -0,0 +1,196 @@
+/*
+ *  Copyright (c) 2019, 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
+ * @run testng TestSegments
+ */
+
+import jdk.incubator.foreign.MemoryLayout;
+import jdk.incubator.foreign.MemoryLayouts;
+import jdk.incubator.foreign.MemorySegment;
+
+import java.awt.font.LayoutPath;
+import java.lang.invoke.VarHandle;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.nio.ByteOrder;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.function.LongFunction;
+import java.util.stream.Stream;
+
+import jdk.incubator.foreign.SequenceLayout;
+import org.testng.annotations.*;
+
+import static org.testng.Assert.*;
+
+public class TestSegments {
+
+    @Test(dataProvider = "badSizeAndAlignments", expectedExceptions = IllegalArgumentException.class)
+    public void testBadAllocateAlign(long size, long align) {
+        MemorySegment.allocateNative(size, align);
+    }
+
+    @Test(dataProvider = "badLayouts", expectedExceptions = UnsupportedOperationException.class)
+    public void testBadAllocateLayout(MemoryLayout layout) {
+        MemorySegment.allocateNative(layout);
+    }
+
+    @Test(expectedExceptions = OutOfMemoryError.class)
+    public void testAllocateTooBig() {
+        MemorySegment.allocateNative(Long.MAX_VALUE);
+    }
+
+    @Test(dataProvider = "segmentOperations")
+    public void testOpOutsideConfinement(SegmentMember member) throws Throwable {
+        try (MemorySegment segment = MemorySegment.allocateNative(4)) {
+            AtomicBoolean failed = new AtomicBoolean(false);
+            Thread t = new Thread(() -> {
+                try {
+                    Object o = member.method.invoke(segment, member.params);
+                    if (member.method.getName().equals("acquire")) {
+                        ((MemorySegment)o).close();
+                    }
+                } catch (ReflectiveOperationException ex) {
+                    throw new IllegalStateException(ex);
+                }
+            });
+            t.setUncaughtExceptionHandler((thread, ex) -> failed.set(true));
+            t.start();
+            t.join();
+            assertEquals(failed.get(), member.isConfined());
+        }
+    }
+
+    @Test
+    public void testNativeSegmentIsZeroed() {
+        VarHandle byteHandle = MemoryLayout.ofSequence(MemoryLayouts.JAVA_BYTE)
+                .varHandle(byte.class, MemoryLayout.PathElement.sequenceElement());
+        try (MemorySegment segment = MemorySegment.allocateNative(1000)) {
+            for (long i = 0 ; i < segment.byteSize() ; i++) {
+                assertEquals(0, (byte)byteHandle.get(segment.baseAddress(), i));
+            }
+        }
+    }
+
+    @DataProvider(name = "badSizeAndAlignments")
+    public Object[][] sizesAndAlignments() {
+        return new Object[][] {
+                { -1, 8 },
+                { 1, 15 },
+                { 1, -15 }
+        };
+    }
+
+    @DataProvider(name = "badLayouts")
+    public Object[][] layouts() {
+        SizedLayoutFactory[] layoutFactories = SizedLayoutFactory.values();
+        Object[][] values = new Object[layoutFactories.length * 2][2];
+        for (int i = 0; i < layoutFactories.length ; i++) {
+            values[i * 2] = new Object[] { MemoryLayout.ofStruct(layoutFactories[i].make(7), MemoryLayout.ofPaddingBits(9)) }; // good size, bad align
+            values[(i * 2) + 1] = new Object[] { layoutFactories[i].make(15).withBitAlignment(16) }; // bad size, good align
+        }
+        return values;
+    }
+
+    enum SizedLayoutFactory {
+        VALUE_BE(size -> MemoryLayout.ofValueBits(size, ByteOrder.BIG_ENDIAN)),
+        VALUE_LE(size -> MemoryLayout.ofValueBits(size, ByteOrder.LITTLE_ENDIAN)),
+        PADDING(MemoryLayout::ofPaddingBits);
+
+        private final LongFunction<MemoryLayout> factory;
+
+        SizedLayoutFactory(LongFunction<MemoryLayout> factory) {
+            this.factory = factory;
+        }
+
+        MemoryLayout make(long size) {
+            return factory.apply(size);
+        }
+    }
+
+    @DataProvider(name = "segmentOperations")
+    static Object[][] segmentMembers() {
+        List<SegmentMember> members = new ArrayList<>();
+        for (Method m : MemorySegment.class.getDeclaredMethods()) {
+            //skip statics and method declared in j.l.Object
+            if (m.getDeclaringClass().equals(Object.class) ||
+                    (m.getModifiers() & Modifier.STATIC) != 0) continue;
+            Object[] args = Stream.of(m.getParameterTypes())
+                    .map(TestSegments::defaultValue)
+                    .toArray();
+            members.add(new SegmentMember(m, args));
+        }
+        return members.stream().map(ms -> new Object[] { ms }).toArray(Object[][]::new);
+    }
+
+    static class SegmentMember {
+        final Method method;
+        final Object[] params;
+
+        public SegmentMember(Method method, Object[] params) {
+            this.method = method;
+            this.params = params;
+        }
+
+        boolean isConfined() {
+            return method.getName().startsWith("as") ||
+                    method.getName().startsWith("to") ||
+                    method.getName().equals("close") ||
+                    method.getName().equals("slice");
+        }
+
+        @Override
+        public String toString() {
+            return method.getName();
+        }
+    }
+
+    static Object defaultValue(Class<?> c) {
+        if (c.isPrimitive()) {
+            if (c == char.class) {
+                return (char)0;
+            } else if (c == boolean.class) {
+                return false;
+            } else if (c == byte.class) {
+                return (byte)0;
+            } else if (c == short.class) {
+                return (short)0;
+            } else if (c == int.class) {
+                return 0;
+            } else if (c == long.class) {
+                return 0L;
+            } else if (c == float.class) {
+                return 0f;
+            } else if (c == double.class) {
+                return 0d;
+            } else {
+                throw new IllegalStateException();
+            }
+        } else {
+            return null;
+        }
+    }
+}