testlrumap.java

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        assertEquals("c", map.entry.getValue());  // entry is reused
        assertEquals(false, map.containsKey("A"));
        assertEquals(true, map.containsKey("B"));
        assertEquals(true, map.containsKey("C"));
    }
    
    static class MockLRUMapSubclass extends LRUMap {
        LinkEntry entry;
        Object key;
        Object value;

        MockLRUMapSubclass(int size) {
            super(size);
        }

        protected boolean removeLRU(LinkEntry entry) {
            this.entry = entry;
            this.key = entry.getKey();
            this.value = entry.getValue();
            return true;
        }
    }
    
    public void testRemoveLRUBlocksRemove() {
        MockLRUMapSubclassBlocksRemove map = new MockLRUMapSubclassBlocksRemove(2, false);
        assertEquals(0, map.size());
        map.put("A", "a");
        assertEquals(1, map.size());
        map.put("B", "b");
        assertEquals(2, map.size());
        map.put("C", "c");  // should remove oldest, which is A=a, but this is blocked
        assertEquals(3, map.size());
        assertEquals(2, map.maxSize());
        assertEquals(true, map.containsKey("A"));
        assertEquals(true, map.containsKey("B"));
        assertEquals(true, map.containsKey("C"));
    }

    public void testRemoveLRUBlocksRemoveScan() {
        MockLRUMapSubclassBlocksRemove map = new MockLRUMapSubclassBlocksRemove(2, true);
        assertEquals(0, map.size());
        map.put("A", "a");
        assertEquals(1, map.size());
        map.put("B", "b");
        assertEquals(2, map.size());
        map.put("C", "c");  // should remove oldest, which is A=a, but this is blocked
        assertEquals(3, map.size());
        assertEquals(2, map.maxSize());
        assertEquals(true, map.containsKey("A"));
        assertEquals(true, map.containsKey("B"));
        assertEquals(true, map.containsKey("C"));
    }
    
    static class MockLRUMapSubclassBlocksRemove extends LRUMap {
        MockLRUMapSubclassBlocksRemove(int size, boolean scanUntilRemove) {
            super(size, scanUntilRemove);
        }

        protected boolean removeLRU(LinkEntry entry) {
            return false;
        }
    }
    
    public void testRemoveLRUFirstBlocksRemove() {
        MockLRUMapSubclassFirstBlocksRemove map = new MockLRUMapSubclassFirstBlocksRemove(2);
        assertEquals(0, map.size());
        map.put("A", "a");
        assertEquals(1, map.size());
        map.put("B", "b");
        assertEquals(2, map.size());
        map.put("C", "c");  // should remove oldest, which is A=a  but this is blocked - so advance to B=b
        assertEquals(2, map.size());
        assertEquals(2, map.maxSize());
        assertEquals(true, map.containsKey("A"));
        assertEquals(false, map.containsKey("B"));
        assertEquals(true, map.containsKey("C"));
    }

    static class MockLRUMapSubclassFirstBlocksRemove extends LRUMap {
        MockLRUMapSubclassFirstBlocksRemove(int size) {
            super(size, true);
        }

        protected boolean removeLRU(LinkEntry entry) {
            if ("a".equals(entry.getValue())) {
                return false;
            } else {
                return true;
            }
        }
    }

    //-----------------------------------------------------------------------
    static class SingleHashCode {
        private final String code;
        SingleHashCode(String code) {
            this.code = code;
        }
        public int hashCode() {
            // always return the same hashcode
            // that way, it will end up in the same bucket
            return 12;
        }
        public String toString() {
            return "SingleHashCode:" + code;
        }
    }

    public void testInternalState_Buckets() {
        if (isPutAddSupported() == false || isPutChangeSupported() == false) return;
        SingleHashCode one = new SingleHashCode("1");
        SingleHashCode two = new SingleHashCode("2");
        SingleHashCode three = new SingleHashCode("3");
        SingleHashCode four = new SingleHashCode("4");
        SingleHashCode five = new SingleHashCode("5");
        SingleHashCode six = new SingleHashCode("6");

        LRUMap map = new LRUMap(3, 1.0f);
        int hashIndex = map.hashIndex(map.hash(one), 4);
        map.put(one, "A");
        map.put(two, "B");
        map.put(three, "C");
        
        assertEquals(4, map.data.length);
        assertEquals(3, map.size);
        assertEquals(null, map.header.next);
        assertEquals(one, map.header.after.key);  // LRU
        assertEquals(two, map.header.after.after.key);
        assertEquals(three, map.header.after.after.after.key);  // MRU
        assertEquals(three, map.data[hashIndex].key);
        assertEquals(two, map.data[hashIndex].next.key);
        assertEquals(one, map.data[hashIndex].next.next.key);
        
        map.put(four, "D");  // reuses last in next list
        
        assertEquals(4, map.data.length);
        assertEquals(3, map.size);
        assertEquals(null, map.header.next);
        assertEquals(two, map.header.after.key);  // LRU
        assertEquals(three, map.header.after.after.key);
        assertEquals(four, map.header.after.after.after.key);  // MRU
        assertEquals(four, map.data[hashIndex].key);
        assertEquals(three, map.data[hashIndex].next.key);
        assertEquals(two, map.data[hashIndex].next.next.key);
        
        map.get(three);
        
        assertEquals(4, map.data.length);
        assertEquals(3, map.size);
        assertEquals(null, map.header.next);
        assertEquals(two, map.header.after.key);  // LRU
        assertEquals(four, map.header.after.after.key);
        assertEquals(three, map.header.after.after.after.key);  // MRU
        assertEquals(four, map.data[hashIndex].key);
        assertEquals(three, map.data[hashIndex].next.key);
        assertEquals(two, map.data[hashIndex].next.next.key);
        
        map.put(five, "E");  // reuses last in next list
        
        assertEquals(4, map.data.length);
        assertEquals(3, map.size);
        assertEquals(null, map.header.next);
        assertEquals(four, map.header.after.key);  // LRU
        assertEquals(three, map.header.after.after.key);
        assertEquals(five, map.header.after.after.after.key);  // MRU
        assertEquals(five, map.data[hashIndex].key);
        assertEquals(four, map.data[hashIndex].next.key);
        assertEquals(three, map.data[hashIndex].next.next.key);
        
        map.get(three);
        map.get(five);
        
        assertEquals(4, map.data.length);
        assertEquals(3, map.size);
        assertEquals(null, map.header.next);
        assertEquals(four, map.header.after.key);  // LRU
        assertEquals(three, map.header.after.after.key);
        assertEquals(five, map.header.after.after.after.key);  // MRU
        assertEquals(five, map.data[hashIndex].key);
        assertEquals(four, map.data[hashIndex].next.key);
        assertEquals(three, map.data[hashIndex].next.next.key);
        
        map.put(six, "F");  // reuses middle in next list
        
        assertEquals(4, map.data.length);
        assertEquals(3, map.size);
        assertEquals(null, map.header.next);
        assertEquals(three, map.header.after.key);  // LRU
        assertEquals(five, map.header.after.after.key);
        assertEquals(six, map.header.after.after.after.key);  // MRU
        assertEquals(six, map.data[hashIndex].key);
        assertEquals(five, map.data[hashIndex].next.key);
        assertEquals(three, map.data[hashIndex].next.next.key);
    }

    public void testInternalState_getEntry_int() {
        if (isPutAddSupported() == false || isPutChangeSupported() == false) return;
        SingleHashCode one = new SingleHashCode("1");
        SingleHashCode two = new SingleHashCode("2");
        SingleHashCode three = new SingleHashCode("3");
        SingleHashCode four = new SingleHashCode("4");
        SingleHashCode five = new SingleHashCode("5");
        SingleHashCode six = new SingleHashCode("6");

        LRUMap map = new LRUMap(3, 1.0f);
        int hashIndex = map.hashIndex(map.hash(one), 4);
        map.put(one, "A");
        map.put(two, "B");
        map.put(three, "C");
        
        assertEquals(one, map.getEntry(0).key);
        assertEquals(two, map.getEntry(1).key);
        assertEquals(three, map.getEntry(2).key);
        try {
            map.getEntry(-1);
            fail();
        } catch (IndexOutOfBoundsException ex) {}
        try {
            map.getEntry(3);
            fail();
        } catch (IndexOutOfBoundsException ex) {}
    }

//    public void testCreate() throws Exception {
//        resetEmpty();
//        writeExternalFormToDisk((java.io.Serializable) map, "D:/dev/collections/data/test/LRUMap.emptyCollection.version3.obj");
//        resetFull();
//        writeExternalFormToDisk((java.io.Serializable) map, "D:/dev/collections/data/test/LRUMap.fullCollection.version3.obj");
//    }
}