/*
 * *************************************************************************************
 *  Copyright (C) 2008 EsperTech, Inc. All rights reserved.                            *
 *  http://esper.codehaus.org                                                          *
 *  http://www.espertech.com                                                           *
 *  ---------------------------------------------------------------------------------- *
 *  The software in this package is published under the terms of the GPL license       *
 *  a copy of which has been included with this distribution in the license.txt file.  *
 * *************************************************************************************
 */

package com.espertech.esper.epl.db;

import junit.framework.TestCase;
import com.espertech.esper.epl.join.table.EventTable;
import com.espertech.esper.epl.join.table.UnindexedEventTable;

public class TestDataCacheLRUImpl extends TestCase
{
    private DataCacheLRUImpl cache;
    private EventTable[] lists = new EventTable[10];

    public void setUp()
    {
        cache = new DataCacheLRUImpl(3);
        for (int i = 0; i < lists.length; i++)
        {
            lists[i] = new UnindexedEventTable(0);
        }
    }

    public void testGet()
    {
        assertNull(cache.getCached(make("a")));
        assertTrue(cache.isActive());

        cache.put(make("a"), lists[0]);     // a
        assertSame(lists[0], cache.getCached(make("a")));

        cache.put(make("b"), lists[1]);     // b, a
        assertSame(lists[1], cache.getCached(make("b"))); // b, a

        assertSame(lists[0], cache.getCached(make("a"))); // a, b

        cache.put(make("c"), lists[2]);     // c, a, b
        cache.put(make("d"), lists[3]);     // d, c, a  (b gone)

        assertNull(cache.getCached(make("b")));

        assertEquals(lists[2], cache.getCached(make("c"))); // c, d, a
        assertEquals(lists[0], cache.getCached(make("a"))); // a, c, d

        cache.put(make("e"), lists[4]); // e, a, c (d and b gone)

        assertNull(cache.getCached(make("d")));
        assertNull(cache.getCached(make("b")));
    }

    private Object[] make(String key)
    {
        return new Object[] {key};
    }
}