TestMutableKeyBuffer.java

/**

Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016.  All rights reserved.

Contact:
     SYSTAP, LLC DBA Blazegraph
     2501 Calvert ST NW #106
     Washington, DC 20008
     licenses@blazegraph.com

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.

This program 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 for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/
/*
 * Created on Jan 22, 2007
 */

package com.bigdata.btree.raba;


/**
 * @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
 * @version $Id$
 */
public class TestMutableKeyBuffer extends AbstractKeyBufferTestCase {

    /**
     * 
     */
    public TestMutableKeyBuffer() {
    }

    /**
     * @param name
     */
    public TestMutableKeyBuffer(String name) {
        super(name);
    }

    /**
     * Test for key mutation operations (adding, removing, inserting, etc).
     */
    public void test_mutation() {
        
        MutableKeyBuffer kbuf = new MutableKeyBuffer(3);
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("keys.length",3,kbuf.keys.length);
        assertEquals("maxKeys",3,kbuf.capacity());
        assertEquals("nkeys",0,kbuf.nkeys);
        assertNull(kbuf.keys[0]);
        assertEquals("prefixLength",0,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{},kbuf.getPrefix());
        
        byte[] k1 = new byte[]{1,2,3};
        assertEquals("nkeys",1,kbuf.add(k1));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",1,kbuf.nkeys);
        assertFalse(kbuf.isFull());
        assertEquals(k1,kbuf.keys[0]);
        assertEquals("prefixLength",3,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2,3},kbuf.getPrefix());

        byte[] k2 = new byte[]{1,2,4};
        assertEquals("nkeys",2,kbuf.add(k2));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",2,kbuf.nkeys);
        assertFalse(kbuf.isFull());
        assertEquals(k1,kbuf.keys[0]);
        assertEquals(k2,kbuf.keys[1]);
        assertEquals("prefixLength",2,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2},kbuf.getPrefix());

        byte[] k3 = new byte[]{1,2,5};
        assertEquals("nkeys",3,kbuf.add(k3));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",3,kbuf.nkeys);
        assertTrue(kbuf.isFull());
        assertEquals(k1,kbuf.keys[0]);
        assertEquals(k2,kbuf.keys[1]);
        assertEquals(k3,kbuf.keys[2]);
        assertEquals("prefixLength",2,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2},kbuf.getPrefix());
        
        // remove the 1st key, leaving two keys.
        assertEquals("nkeys",2,kbuf.remove(0));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",2,kbuf.nkeys);
        assertFalse(kbuf.isFull());
        assertEquals(k2,kbuf.keys[0]);
        assertEquals(k3,kbuf.keys[1]);
        assertNull(kbuf.keys[2]);
        assertEquals("prefixLength",2,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2},kbuf.getPrefix());
        
        // remove the last key, leaving one key.
        assertEquals("nkeys",1,kbuf.remove(1));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",1,kbuf.nkeys);
        assertFalse(kbuf.isFull());
        assertEquals(k2,kbuf.keys[0]);
        assertNull(kbuf.keys[1]);
        assertNull(kbuf.keys[2]);
        assertEquals("prefixLength",3,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2,4},kbuf.getPrefix());
        
        // insert a key in the 1st position (two keys in the buffer).
        assertEquals("nkeys",2,kbuf.insert(0,k1));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",2,kbuf.nkeys);
        assertFalse(kbuf.isFull());
        assertEquals(k1,kbuf.keys[0]);
        assertEquals(k2,kbuf.keys[1]);
        assertNull(kbuf.keys[2]);
        assertEquals("prefixLength",2,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2},kbuf.getPrefix());

        // insert a key in the 2nd position (three keys in the buffer).
        byte[] k4 = new byte[]{1,2,3,0};
        assertEquals("nkeys",3,kbuf.insert(1,k4));
        if(log.isInfoEnabled()) log.info(kbuf.toString());
        assertEquals("nkeys",3,kbuf.nkeys);
        assertTrue(kbuf.isFull());
        assertEquals(k1,kbuf.keys[0]);
        assertEquals(k4,kbuf.keys[1]);
        assertEquals(k2,kbuf.keys[2]);
        assertEquals("prefixLength",2,kbuf.getPrefixLength());
        assertEquals("prefix",new byte[]{1,2},kbuf.getPrefix());

    }
    
    public void test_getPrefixLength() {

        MutableKeyBuffer kbuf = new MutableKeyBuffer(3);
        
        /*
         * no keys - zero length prefix.
         */
        assertEquals(0,kbuf.getPrefixLength());

        /*
         * one keys - prefix length is the length of that key.
         */
        kbuf.nkeys = 1;
        kbuf.keys[0] = new byte[]{2,3,5};
        assertEquals(3,kbuf.getPrefixLength());
        
        /*
         * more than one key - prefix length is the #of leading bytes in common.
         * between the first and last keys.
         */
        kbuf.nkeys = 2;
        kbuf.keys[1] = new byte[]{2,4};
        assertEquals(1,kbuf.getPrefixLength());

    }

}