jdk/test/java/util/Collection/MOAT.java
changeset 2 90ce3da70b43
child 493 b8102e80be10
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/util/Collection/MOAT.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,814 @@
+/*
+ * Copyright 2005-2007 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug     6207984 6272521 6192552 6269713 6197726 6260652 5073546 4137464
+ *          4155650 4216399 4294891 6282555 6318622 6355327 6383475 6420753
+ *          6431845 4802633 6570566 6570575 6570631 6570924
+ * @summary Run many tests on many Collection and Map implementations
+ * @author  Martin Buchholz
+ */
+
+/* Mother Of All (Collection) Tests
+ *
+ * Testing of collection classes is often spotty, because many tests
+ * need to be performed on many implementations, but the onus on
+ * writing the tests falls on the engineer introducing the new
+ * implementation.
+ *
+ * The idea of this mega-test is that:
+ *
+ * An engineer adding a new collection implementation could simply add
+ * their new implementation to a list of implementations in this
+ * test's main method.  Any general purpose Collection<Integer> or
+ * Map<Integer,Integer> class is appropriate.
+ *
+ * An engineer fixing a regression could add their regression test here and
+ * simultaneously test all other implementations.
+ */
+
+import java.io.*;
+import java.util.*;
+import java.util.concurrent.*;
+import static java.util.Collections.*;
+
+public class MOAT {
+    public static void realMain(String[] args) {
+
+        testCollection(new LinkedHashSet<Integer>());
+        testCollection(new HashSet<Integer>());
+        testCollection(new Vector<Integer>());
+        testCollection(new Vector<Integer>().subList(0,0));
+        testCollection(new ArrayDeque<Integer>());
+        testCollection(new ArrayList<Integer>());
+        testCollection(new ArrayList<Integer>().subList(0,0));
+        testCollection(new LinkedList<Integer>());
+        testCollection(new LinkedList<Integer>().subList(0,0));
+        testCollection(new TreeSet<Integer>());
+
+        testCollection(new CopyOnWriteArrayList<Integer>());
+        testCollection(new CopyOnWriteArrayList<Integer>().subList(0,0));
+        testCollection(new CopyOnWriteArraySet<Integer>());
+        testCollection(new PriorityQueue<Integer>());
+        testCollection(new PriorityBlockingQueue<Integer>());
+        testCollection(new ArrayBlockingQueue<Integer>(20));
+        testCollection(new LinkedBlockingQueue<Integer>(20));
+        testCollection(new LinkedBlockingDeque<Integer>(20));
+        testCollection(new ConcurrentLinkedQueue<Integer>());
+        testCollection(new ConcurrentSkipListSet<Integer>());
+        testCollection(Arrays.asList(new Integer(42)));
+        testCollection(Arrays.asList(1,2,3));
+        testCollection(nCopies(25,1));
+        testImmutableList(nCopies(25,1));
+        testImmutableList(unmodifiableList(Arrays.asList(1,2,3)));
+
+        testMap(new HashMap<Integer,Integer>());
+        testMap(new LinkedHashMap<Integer,Integer>());
+        testMap(new WeakHashMap<Integer,Integer>());
+        testMap(new IdentityHashMap<Integer,Integer>());
+        testMap(new TreeMap<Integer,Integer>());
+        testMap(new Hashtable<Integer,Integer>());
+        testMap(new ConcurrentHashMap<Integer,Integer>(10, 0.5f));
+        testMap(new ConcurrentSkipListMap<Integer,Integer>());
+
+        // Empty collections
+        final List<Integer> emptyArray = Arrays.asList(new Integer[]{});
+        testCollection(emptyArray);
+        testEmptyList(emptyArray);
+        THROWS(IndexOutOfBoundsException.class,
+               new Fun(){void f(){ emptyArray.set(0,1); }});
+        THROWS(UnsupportedOperationException.class,
+               new Fun(){void f(){ emptyArray.add(0,1); }});
+
+        List<Integer> noOne = nCopies(0,1);
+        testCollection(noOne);
+        testEmptyList(noOne);
+        testImmutableList(noOne);
+
+        Set<Integer> emptySet = emptySet();
+        testCollection(emptySet);
+        testEmptySet(emptySet);
+        testEmptySet(EMPTY_SET);
+        testImmutableSet(emptySet);
+
+        List<Integer> emptyList = emptyList();
+        testCollection(emptyList);
+        testEmptyList(emptyList);
+        testEmptyList(EMPTY_LIST);
+        testImmutableList(emptyList);
+
+        Map<Integer,Integer> emptyMap = emptyMap();
+        testMap(emptyMap);
+        testEmptyMap(emptyMap);
+        testEmptyMap(EMPTY_MAP);
+        testImmutableMap(emptyMap);
+
+        // Singleton collections
+        Set<Integer> singletonSet = singleton(1);
+        equal(singletonSet.size(), 1);
+        testCollection(singletonSet);
+        testImmutableSet(singletonSet);
+
+        List<Integer> singletonList = singletonList(1);
+        equal(singletonList.size(), 1);
+        testCollection(singletonList);
+        testImmutableList(singletonList);
+        testImmutableList(singletonList.subList(0,1));
+        testImmutableList(singletonList.subList(0,1).subList(0,1));
+        testEmptyList(singletonList.subList(0,0));
+        testEmptyList(singletonList.subList(0,0).subList(0,0));
+
+        Map<Integer,Integer> singletonMap = singletonMap(1,2);
+        equal(singletonMap.size(), 1);
+        testMap(singletonMap);
+        testImmutableMap(singletonMap);
+    }
+
+    private static void checkContainsSelf(Collection<Integer> c) {
+        check(c.containsAll(c));
+        check(c.containsAll(Arrays.asList(c.toArray())));
+        check(c.containsAll(Arrays.asList(c.toArray(new Integer[0]))));
+    }
+
+    private static void checkContainsEmpty(Collection<Integer> c) {
+        check(c.containsAll(new ArrayList<Integer>()));
+    }
+
+    private static void testEmptyCollection(Collection<?> c) {
+        check(c.isEmpty());
+        equal(c.size(), 0);
+        equal(c.toString(),"[]");
+        equal(c.toArray().length, 0);
+        equal(c.toArray(new Object[0]).length, 0);
+
+        Object[] a = new Object[1]; a[0] = Boolean.TRUE;
+        equal(c.toArray(a), a);
+        equal(a[0], null);
+    }
+
+    private static void testEmptyList(List<?> c) {
+        testEmptyCollection(c);
+        equal(c.hashCode(), 1);
+        equal2(c, Collections.<Integer>emptyList());
+    }
+
+    private static void testEmptySet(Set<?> c) {
+        testEmptyCollection(c);
+        equal(c.hashCode(), 0);
+        equal2(c, Collections.<Integer>emptySet());
+    }
+
+    private static void testImmutableCollection(final Collection<Integer> c) {
+        THROWS(UnsupportedOperationException.class,
+               new Fun(){void f(){ c.add(99); }},
+               new Fun(){void f(){ c.addAll(singleton(99)); }});
+        if (! c.isEmpty()) {
+            final Integer first = c.iterator().next();
+            THROWS(UnsupportedOperationException.class,
+                   new Fun(){void f(){ c.clear(); }},
+                   new Fun(){void f(){ c.remove(first); }},
+                   new Fun(){void f(){ c.removeAll(singleton(first)); }},
+                   new Fun(){void f(){ c.retainAll(emptyList()); }}
+                   );
+        }
+    }
+
+    private static void testImmutableSet(final Set<Integer> c) {
+        testImmutableCollection(c);
+    }
+
+    private static void testImmutableList(final List<Integer> c) {
+        testList(c);
+        testImmutableCollection(c);
+        THROWS(UnsupportedOperationException.class,
+               new Fun(){void f(){ c.set(0,42); }},
+               new Fun(){void f(){ c.add(0,42); }},
+               new Fun(){void f(){ c.addAll(0,singleton(86)); }});
+        if (! c.isEmpty())
+            THROWS(UnsupportedOperationException.class,
+                   new Fun(){void f(){
+                           Iterator<Integer> it = c.iterator();
+                           it.next(); it.remove();}},
+                   new Fun(){void f(){
+                           ListIterator<Integer> it = c.listIterator();
+                           it.next(); it.remove();}});
+    }
+
+    private static void clear(Collection<Integer> c) {
+        try { c.clear(); }
+        catch (Throwable t) { unexpected(t); }
+        testEmptyCollection(c);
+    }
+
+    private static void testEmptyMap(final Map<?,?> m) {
+        check(m.isEmpty());
+        equal(m.size(), 0);
+        equal(m.toString(),"{}");
+        testEmptySet(m.keySet());
+        testEmptySet(m.entrySet());
+        testEmptyCollection(m.values());
+    }
+
+    private static void testImmutableMap(final Map<Integer,Integer> m) {
+        THROWS(UnsupportedOperationException.class,
+               new Fun(){void f(){ m.put(1,1); }},
+               new Fun(){void f(){ m.putAll(singletonMap(1,1)); }});
+        if (! m.isEmpty()) {
+            final Integer first = m.keySet().iterator().next();
+            THROWS(UnsupportedOperationException.class,
+                   new Fun(){void f(){ m.remove(first); }},
+                   new Fun(){void f(){ m.clear(); }});
+            final Map.Entry<Integer,Integer> me
+                = m.entrySet().iterator().next();
+            Integer key = me.getKey();
+            Integer val = me.getValue();
+            THROWS(UnsupportedOperationException.class,
+                   new Fun(){void f(){ me.setValue(3); }});
+            equal(key, me.getKey());
+            equal(val, me.getValue());
+        }
+        testImmutableSet(m.keySet());
+        testImmutableCollection(m.values());
+        //testImmutableSet(m.entrySet());
+    }
+
+    private static void clear(Map<?,?> m) {
+        try { m.clear(); }
+        catch (Throwable t) { unexpected(t); }
+        testEmptyMap(m);
+    }
+
+    private static void oneElement(Collection<Integer> c) {
+        clear(c);
+        try {
+            check(c.add(-42));
+            equal(c.toString(), "[-42]");
+            if (c instanceof Set) check(! c.add(-42));
+        } catch (Throwable t) { unexpected(t); }
+        check(! c.isEmpty()); check(c.size() == 1);
+    }
+
+    private static boolean supportsAdd(Collection<Integer> c) {
+        try { check(c.add(778347983)); }
+        catch (UnsupportedOperationException t) { return false; }
+        catch (Throwable t) { unexpected(t); }
+
+        try {
+            check(c.contains(778347983));
+            check(c.remove(778347983));
+        } catch (Throwable t) { unexpected(t); }
+        return true;
+    }
+
+    private static boolean supportsRemove(Collection<Integer> c) {
+        try { check(! c.remove(19134032)); }
+        catch (UnsupportedOperationException t) { return false; }
+        catch (Throwable t) { unexpected(t); }
+        return true;
+    }
+
+    private static void checkFunctionalInvariants(Collection<Integer> c) {
+        try {
+            checkContainsSelf(c);
+            checkContainsEmpty(c);
+            check(c.size() != 0 ^ c.isEmpty());
+
+            {
+                int size = 0;
+                for (Integer i : c) size++;
+                check(c.size() == size);
+            }
+
+            check(c.toArray().length == c.size());
+            check(c.toArray().getClass() == Object[].class
+                  ||
+                  // !!!!
+                  // 6260652: (coll) Arrays.asList(x).toArray().getClass()
+                  // should be Object[].class
+                  (c.getClass().getName().equals("java.util.Arrays$ArrayList"))
+                  );
+            for (int size : new int[]{0,1,c.size(), c.size()+1}) {
+                Integer[] a = c.toArray(new Integer[size]);
+                check((size > c.size()) || a.length == c.size());
+                int i = 0; for (Integer j : c) check(a[i++] == j);
+                check((size <= c.size()) || (a[c.size()] == null));
+                check(a.getClass() == Integer[].class);
+            }
+
+            check(c.equals(c));
+            if (c instanceof Serializable) {
+                //System.out.printf("Serializing %s%n", c.getClass().getName());
+                try {
+                    Object clone = serialClone(c);
+                    equal(c instanceof Serializable,
+                          clone instanceof Serializable);
+                    equal(c instanceof RandomAccess,
+                          clone instanceof RandomAccess);
+                    if ((c instanceof List) || (c instanceof Set))
+                        equal(c, clone);
+                    else
+                        equal(new HashSet<Integer>(c),
+                              new HashSet<Integer>(serialClone(c)));
+                } catch (Error xxx) {
+                    if (! (xxx.getCause() instanceof NotSerializableException))
+                        throw xxx;
+                }
+            }
+        }
+        catch (Throwable t) { unexpected(t); }
+    }
+
+    //----------------------------------------------------------------
+    // If add(null) succeeds, contains(null) & remove(null) should succeed
+    //----------------------------------------------------------------
+    private static void testNullElement(Collection<Integer> c) {
+        // !!!! 5018849: (coll) TreeSet.contains(null) does not agree with Javadoc
+        if (c instanceof TreeSet) return;
+
+        try {
+            check(c.add(null));
+            if (c.size() == 1)
+                equal(c.toString(), "[null]");
+            try {
+                checkFunctionalInvariants(c);
+                check(c.contains(null));
+                check(c.remove(null));
+            }
+            catch (Throwable t) { unexpected(t); }
+        }
+        catch (NullPointerException e) { /* OK */ }
+        catch (Throwable t) { unexpected(t); }
+    }
+
+
+    //----------------------------------------------------------------
+    // If add("x") succeeds, contains("x") & remove("x") should succeed
+    //----------------------------------------------------------------
+    @SuppressWarnings("unchecked")
+    private static void testStringElement(Collection<Integer> c) {
+        Collection x = (Collection)c; // Make type-unsafe
+        try {
+            check(x.add("x"));
+            try {
+                check(x.contains("x"));
+                check(x.remove("x"));
+            } catch (Throwable t) { unexpected(t); }
+        }
+        catch (ClassCastException e) { /* OK */ }
+        catch (Throwable t) { unexpected(t); }
+    }
+
+    private static void testConcurrentCollection(Collection<Integer> c) {
+        try {
+            c.add(1);
+            Iterator<Integer> it = c.iterator();
+            check(it.hasNext());
+            clear(c);
+            check(it.next() instanceof Integer); // No CME
+            check(c.isEmpty());
+        }
+        catch (Throwable t) { unexpected(t); }
+    }
+
+    private static void testQueue(Queue<Integer> q) {
+        q.clear();
+        for (int i = 0; i < 5; i++)
+            q.add(i);
+        equal(q.size(), 5);
+        checkFunctionalInvariants(q);
+        q.poll();
+        equal(q.size(), 4);
+        checkFunctionalInvariants(q);
+    }
+
+    private static void testList(final List<Integer> l) {
+        //----------------------------------------------------------------
+        // 4802633: (coll) AbstractList.addAll(-1,emptyCollection)
+        // doesn't throw IndexOutOfBoundsException
+        //----------------------------------------------------------------
+        try {
+            l.addAll(-1, Collections.<Integer>emptyList());
+            fail("Expected IndexOutOfBoundsException not thrown");
+        }
+        catch (UnsupportedOperationException _) {/* OK */}
+        catch (IndexOutOfBoundsException _) {/* OK */}
+        catch (Throwable t) { unexpected(t); }
+
+//      equal(l instanceof Serializable,
+//            l.subList(0,0) instanceof Serializable);
+        if (l.subList(0,0) instanceof Serializable)
+            check(l instanceof Serializable);
+
+        equal(l instanceof RandomAccess,
+              l.subList(0,0) instanceof RandomAccess);
+    }
+
+    private static void testCollection(Collection<Integer> c) {
+
+        System.out.println("\n==> " + c.getClass().getName());
+
+        checkFunctionalInvariants(c);
+
+        if (! supportsAdd(c)) return;
+        //System.out.println("add() supported");
+
+        if (c instanceof NavigableSet)
+            testNavigableSet((NavigableSet<Integer>)c);
+
+        if (c instanceof Queue)
+            testQueue((Queue<Integer>)c);
+
+        if (c instanceof List)
+            testList((List<Integer>)c);
+
+        check(supportsRemove(c));
+
+        try {
+            oneElement(c);
+            checkFunctionalInvariants(c);
+        }
+        catch (Throwable t) { unexpected(t); }
+
+        clear(c);      testNullElement(c);
+        oneElement(c); testNullElement(c);
+
+        clear(c);      testStringElement(c);
+        oneElement(c); testStringElement(c);
+
+        if (c.getClass().getName().matches(".*concurrent.*"))
+            testConcurrentCollection(c);
+
+        //----------------------------------------------------------------
+        // The "all" operations should throw NPE when passed null
+        //----------------------------------------------------------------
+        {
+            oneElement(c);
+            try {
+                c.removeAll(null);
+                fail("Expected NullPointerException");
+            }
+            catch (NullPointerException e) { pass(); }
+            catch (Throwable t) { unexpected(t); }
+
+            oneElement(c);
+            try {
+                c.retainAll(null);
+                fail("Expected NullPointerException");
+            }
+            catch (NullPointerException e) { pass(); }
+            catch (Throwable t) { unexpected(t); }
+
+            oneElement(c);
+            try {
+                c.addAll(null);
+                fail("Expected NullPointerException");
+            }
+            catch (NullPointerException e) { pass(); }
+            catch (Throwable t) { unexpected(t); }
+
+            oneElement(c);
+            try {
+                c.containsAll(null);
+                fail("Expected NullPointerException");
+            }
+            catch (NullPointerException e) { pass(); }
+            catch (Throwable t) { unexpected(t); }
+        }
+    }
+
+    //----------------------------------------------------------------
+    // Map
+    //----------------------------------------------------------------
+    private static void checkFunctionalInvariants(Map<Integer,Integer> m) {
+        check(m.keySet().size() == m.entrySet().size());
+        check(m.keySet().size() == m.size());
+        checkFunctionalInvariants(m.keySet());
+        checkFunctionalInvariants(m.values());
+        check(m.size() != 0 ^ m.isEmpty());
+    }
+
+    private static void testMap(Map<Integer,Integer> m) {
+        System.out.println("\n==> " + m.getClass().getName());
+
+        if (m instanceof ConcurrentMap)
+            testConcurrentMap((ConcurrentMap<Integer,Integer>) m);
+
+        if (m instanceof NavigableMap)
+            testNavigableMap((NavigableMap<Integer,Integer>) m);
+
+        checkFunctionalInvariants(m);
+
+        if (supportsClear(m)) {
+            try { clear(m); }
+            catch (Throwable t) { unexpected(t); }
+        }
+
+        if (supportsPut(m)) {
+            try {
+                check(m.put(3333, 77777) == null);
+                check(m.put(9134, 74982) == null);
+                check(m.get(9134) == 74982);
+                check(m.put(9134, 1382) == 74982);
+                check(m.get(9134) == 1382);
+                check(m.size() == 2);
+                checkFunctionalInvariants(m);
+                checkNPEConsistency(m);
+            }
+            catch (Throwable t) { unexpected(t); }
+        }
+    }
+
+    private static boolean supportsPut(Map<Integer,Integer> m) {
+        // We're asking for .equals(...) semantics
+        if (m instanceof IdentityHashMap) return false;
+
+        try { check(m.put(778347983,12735) == null); }
+        catch (UnsupportedOperationException t) { return false; }
+        catch (Throwable t) { unexpected(t); }
+
+        try {
+            check(m.containsKey(778347983));
+            check(m.remove(778347983) != null);
+        } catch (Throwable t) { unexpected(t); }
+        return true;
+    }
+
+    private static boolean supportsClear(Map<?,?> m) {
+        try { m.clear(); }
+        catch (UnsupportedOperationException t) { return false; }
+        catch (Throwable t) { unexpected(t); }
+        return true;
+    }
+
+    //----------------------------------------------------------------
+    // ConcurrentMap
+    //----------------------------------------------------------------
+    private static void testConcurrentMap(ConcurrentMap<Integer,Integer> m) {
+        System.out.println("ConcurrentMap tests...");
+
+        try {
+            clear(m);
+
+            check(m.putIfAbsent(18357,7346) == null);
+            check(m.containsKey(18357));
+            check(m.putIfAbsent(18357,8263) == 7346);
+            try { m.putIfAbsent(18357,null); fail("NPE"); }
+            catch (NullPointerException t) { }
+            check(m.containsKey(18357));
+
+            check(! m.replace(18357,8888,7777));
+            check(m.containsKey(18357));
+            try { m.replace(18357,null,7777); fail("NPE"); }
+            catch (NullPointerException t) { }
+            check(m.containsKey(18357));
+            check(m.get(18357) == 7346);
+            check(m.replace(18357,7346,5555));
+            check(m.replace(18357,5555,7346));
+            check(m.get(18357) == 7346);
+
+            check(m.replace(92347,7834) == null);
+            try { m.replace(18357,null); fail("NPE"); }
+            catch (NullPointerException t) { }
+            check(m.replace(18357,7346) == 7346);
+            check(m.replace(18357,5555) == 7346);
+            check(m.get(18357) == 5555);
+            check(m.replace(18357,7346) == 5555);
+            check(m.get(18357) == 7346);
+
+            check(! m.remove(18357,9999));
+            check(m.get(18357) == 7346);
+            check(m.containsKey(18357));
+            check(! m.remove(18357,null)); // 6272521
+            check(m.get(18357) == 7346);
+            check(m.remove(18357,7346));
+            check(m.get(18357) == null);
+            check(! m.containsKey(18357));
+            check(m.isEmpty());
+
+            m.putIfAbsent(1,2);
+            check(m.size() == 1);
+            check(! m.remove(1,null));
+            check(! m.remove(1,null));
+            check(! m.remove(1,1));
+            check(m.remove(1,2));
+            check(m.isEmpty());
+
+            testEmptyMap(m);
+        }
+        catch (Throwable t) { unexpected(t); }
+    }
+
+    private static void throwsConsistently(Class<? extends Throwable> k,
+                                           Iterable<Fun> fs) {
+        List<Class<? extends Throwable>> threw
+            = new ArrayList<Class<? extends Throwable>>();
+        for (Fun f : fs)
+            try { f.f(); threw.add(null); }
+            catch (Throwable t) {
+                check(k.isAssignableFrom(t.getClass()));
+                threw.add(t.getClass());
+            }
+        if (new HashSet<Object>(threw).size() != 1)
+            fail(threw.toString());
+    }
+
+    private static <T> void checkNPEConsistency(final Map<T,Integer> m) {
+        m.clear();
+        final ConcurrentMap<T,Integer> cm = (m instanceof ConcurrentMap)
+            ? (ConcurrentMap<T,Integer>) m
+            : null;
+        List<Fun> fs = new ArrayList<Fun>();
+        fs.add(new Fun(){void f(){ check(! m.containsKey(null));}});
+        fs.add(new Fun(){void f(){ equal(m.remove(null), null);}});
+        fs.add(new Fun(){void f(){ equal(m.get(null), null);}});
+        if (cm != null) {
+            fs.add(new Fun(){void f(){ check(! cm.remove(null,null));}});}
+        throwsConsistently(NullPointerException.class, fs);
+
+        fs.clear();
+        final Map<T,Integer> sm = singletonMap(null,1);
+        fs.add(new Fun(){void f(){ equal(m.put(null,1), null); m.clear();}});
+        fs.add(new Fun(){void f(){ m.putAll(sm); m.clear();}});
+        if (cm != null) {
+            fs.add(new Fun(){void f(){ check(! cm.remove(null,null));}});
+            fs.add(new Fun(){void f(){ equal(cm.putIfAbsent(null,1), 1);}});
+            fs.add(new Fun(){void f(){ equal(cm.replace(null,1), null);}});
+            fs.add(new Fun(){void f(){ equal(cm.replace(null,1, 1), 1);}});
+        }
+        throwsConsistently(NullPointerException.class, fs);
+    }
+
+    //----------------------------------------------------------------
+    // NavigableMap
+    //----------------------------------------------------------------
+    private static void
+        checkNavigableMapKeys(NavigableMap<Integer,Integer> m,
+                              Integer i,
+                              Integer lower,
+                              Integer floor,
+                              Integer ceiling,
+                              Integer higher) {
+        equal(m.lowerKey(i),   lower);
+        equal(m.floorKey(i),   floor);
+        equal(m.ceilingKey(i), ceiling);
+        equal(m.higherKey(i),  higher);
+    }
+
+    private static void
+        checkNavigableSetKeys(NavigableSet<Integer> m,
+                              Integer i,
+                              Integer lower,
+                              Integer floor,
+                              Integer ceiling,
+                              Integer higher) {
+        equal(m.lower(i),   lower);
+        equal(m.floor(i),   floor);
+        equal(m.ceiling(i), ceiling);
+        equal(m.higher(i),  higher);
+    }
+
+    static final Random rnd = new Random();
+    static void equalNext(final Iterator<?> it, Object expected) {
+        if (rnd.nextBoolean())
+            check(it.hasNext());
+        equal(it.next(), expected);
+    }
+
+    private static void testNavigableMap(NavigableMap<Integer,Integer> m)
+    {
+        System.out.println("NavigableMap tests...");
+
+        clear(m);
+        checkNavigableMapKeys(m, 1, null, null, null, null);
+
+        equal(m.put(1, 2), null);
+        equal(m.put(3, 4), null);
+        equal(m.put(5, 9), null);
+
+        equal(m.put(1, 2), 2);
+        equal(m.put(3, 4), 4);
+        equal(m.put(5, 6), 9);
+
+        checkNavigableMapKeys(m, 0, null, null,    1,    1);
+        checkNavigableMapKeys(m, 1, null,    1,    1,    3);
+        checkNavigableMapKeys(m, 2,    1,    1,    3,    3);
+        checkNavigableMapKeys(m, 3,    1,    3,    3,    5);
+        checkNavigableMapKeys(m, 5,    3,    5,    5, null);
+        checkNavigableMapKeys(m, 6,    5,    5, null, null);
+
+        {
+            final Iterator<Integer> it
+                = m.descendingKeySet().iterator();
+            equalNext(it, 5);
+            equalNext(it, 3);
+            equalNext(it, 1);
+            check(! it.hasNext());
+            THROWS(NoSuchElementException.class,
+                   new Fun(){void f(){it.next();}});
+        }
+
+        {
+            final Iterator<Map.Entry<Integer,Integer>> it
+                = m.descendingMap().entrySet().iterator();
+            check(it.hasNext()); equal(it.next().getKey(), 5);
+            check(it.hasNext()); equal(it.next().getKey(), 3);
+            check(it.hasNext()); equal(it.next().getKey(), 1);
+            check(! it.hasNext());
+            THROWS(NoSuchElementException.class,
+                   new Fun(){void f(){it.next();}});
+        }
+    }
+
+
+    private static void testNavigableSet(NavigableSet<Integer> s) {
+        System.out.println("NavigableSet tests...");
+
+        clear(s);
+        checkNavigableSetKeys(s, 1, null, null, null, null);
+
+        check(s.add(1));
+        check(s.add(3));
+        check(s.add(5));
+
+        check(! s.add(1));
+        check(! s.add(3));
+        check(! s.add(5));
+
+        checkNavigableSetKeys(s, 0, null, null,    1,    1);
+        checkNavigableSetKeys(s, 1, null,    1,    1,    3);
+        checkNavigableSetKeys(s, 2,    1,    1,    3,    3);
+        checkNavigableSetKeys(s, 3,    1,    3,    3,    5);
+        checkNavigableSetKeys(s, 5,    3,    5,    5, null);
+        checkNavigableSetKeys(s, 6,    5,    5, null, null);
+
+        {
+            final Iterator<Integer> it = s.descendingIterator();
+            equalNext(it, 5);
+            equalNext(it, 3);
+            equalNext(it, 1);
+            check(! it.hasNext());
+            THROWS(NoSuchElementException.class,
+                   new Fun(){void f(){it.next();}});
+        }
+    }
+
+    //--------------------- Infrastructure ---------------------------
+    static volatile int passed = 0, failed = 0;
+    static void pass() { passed++; }
+    static void fail() { failed++; Thread.dumpStack(); }
+    static void fail(String msg) { System.out.println(msg); fail(); }
+    static void unexpected(Throwable t) { failed++; t.printStackTrace(); }
+    static void check(boolean cond) { if (cond) pass(); else fail(); }
+    static void equal(Object x, Object y) {
+        if (x == null ? y == null : x.equals(y)) pass();
+        else {System.out.println(x + " not equal to " + y); fail();}}
+    static void equal2(Object x, Object y) {equal(x, y); equal(y, x);}
+    public static void main(String[] args) throws Throwable {
+        try { realMain(args); } catch (Throwable t) { unexpected(t); }
+
+        System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);
+        if (failed > 0) throw new Exception("Some tests failed");
+    }
+    private static abstract class Fun {abstract void f() throws Throwable;}
+    private static void THROWS(Class<? extends Throwable> k, Fun... fs) {
+          for (Fun f : fs)
+              try { f.f(); fail("Expected " + k.getName() + " not thrown"); }
+              catch (Throwable t) {
+                  if (k.isAssignableFrom(t.getClass())) pass();
+                  else unexpected(t);}}
+    static byte[] serializedForm(Object obj) {
+        try {
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            new ObjectOutputStream(baos).writeObject(obj);
+            return baos.toByteArray();
+        } catch (IOException e) { throw new Error(e); }}
+    static Object readObject(byte[] bytes)
+        throws IOException, ClassNotFoundException {
+        InputStream is = new ByteArrayInputStream(bytes);
+        return new ObjectInputStream(is).readObject();}
+    @SuppressWarnings("unchecked")
+    static <T> T serialClone(T obj) {
+        try { return (T) readObject(serializedForm(obj)); }
+        catch (Exception e) { throw new Error(e); }}
+}