/**
 * JDBM LICENSE v1.00
 *
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided
 * that the following conditions are met:
 *
 * 1. Redistributions of source code must retain copyright
 *    statements and notices.  Redistributions must also contain a
 *    copy of this document.
 *
 * 2. Redistributions in binary form must reproduce the
 *    above copyright notice, this list of conditions and the
 *    following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. The name "JDBM" must not be used to endorse or promote
 *    products derived from this Software without prior written
 *    permission of Cees de Groot.  For written permission,
 *    please contact cg@cdegroot.com.
 *
 * 4. Products derived from this Software may not be called "JDBM"
 *    nor may "JDBM" appear in their names without prior written
 *    permission of Cees de Groot.
 *
 * 5. Due credit should be given to the JDBM Project
 *    (http://jdbm.sourceforge.net/).
 *
 * THIS SOFTWARE IS PROVIDED BY THE JDBM PROJECT AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
 * CEES DE GROOT OR ANY CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 2000 (C) Cees de Groot. All Rights Reserved.
 * Contributions are Copyright (C) 2000 by their associated contributors.
 *
 */
package jdbm.btree;


import jdbm.RecordManager;
import jdbm.RecordManagerFactory;
import jdbm.helper.StringComparator;
import jdbm.btree.BTree;

import java.io.File;
import java.io.IOException;

import org.junit.Test;

/**
 * Contributed test case for BTree by Christof Dallermassl (cdaller@iicm.edu):
 *
 * -= quote from original message posted on jdbm-general =-
 * <pre>
 *
 * I tried to insert a couple of elements into a BTree and then remove
 * them one by one. After a number or removals, there is always (if more
 * than 20 elements in btree) a java.io.StreamCorruptedException thrown.
 *
 * The strange thing is, that on 50 elements, the exception is thrown
 * after removing 22, on 200 it is thrown after 36, on 1000 it is thrown
 * after 104, on 10000 it is thrown after 1003....
 *
 * The full stackTrace is here:
 * ---------------------- snip ------- snap -------------------------
 * java.io.StreamCorruptedException: Caught EOFException while reading the
 * stream header
 *   at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:845)
 *   at java.io.ObjectInputStream.<init>(ObjectInputStream.java:168)
 *   at jdbm.recman.RecordManager.byteArrayToObject(RecordManager.java:296)
 *   at jdbm.recman.RecordManager.fetchObject(RecordManager.java:239)
 *   at jdbm.helper.ObjectCache.fetchObject(ObjectCache.java:104)
 *   at jdbm.btree.BPage.loadBPage(BPage.java:670)
 *   at jdbm.btree.BPage.remove(BPage.java:492)
 *   at jdbm.btree.BPage.remove(BPage.java:437)
 *   at jdbm.btree.BTree.remove(BTree.java:313)
 *   at JDBMTest.main(JDBMTest.java:41)
 *
 * </pre>
 *
 *  @author <a href="mailto:cdaller@iicm.edu">Christof Dallermassl</a>
 */
public class StreamCorrupted
{
    public final static String testFileName = "test";

    public static void deleteFile( String filename )
    {
        File file = new File( filename );

        if ( file.exists() ) {
            try 
            {
                file.delete();
            } 
            catch ( Exception except ) 
            {
                except.printStackTrace();
            }
            
            if ( file.exists() ) 
            {
                System.out.println( "WARNING:  Cannot delete file: " + file );
            }
        }
    }

    
    public static void deleteTestFile()
    {
        System.gc();
        deleteFile( testFileName);
        deleteFile( testFileName + ".db" );
        deleteFile( testFileName + ".lg" );
    }


    /**
     *  Basic tests
     */
    @Test
    public void testStreamCorrupted() throws IOException
    {
        RecordManager  recman;
        BTree<String, Integer>          btree;
        int            iterations;

        iterations = 100; // 23 works :-(((((

        // open database
        recman = RecordManagerFactory.createRecordManager( testFileName );

        // create a new B+Tree data structure
        btree = new BTree<String, Integer>( recman, new StringComparator() );
        recman.setNamedObject( "testbtree", btree.getRecordId() );

        // action:
        // insert data
        for( int count = 0; count < iterations; count++ ) 
        {
            btree.insert( "num" + count, Integer.valueOf( count ), true );
        }

        // delete data
        for( int count = 0; count < iterations; count++ ) 
        {
            btree.remove( "num" + count );
        }

        // close database
        recman.close();
        recman = null;
    }
}
