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Java > Open Source Codes > com > db4o > test > DeleteDeep


1 /* Copyright (C) 2004 - 2006 db4objects Inc. http://www.db4o.com
2
3 This file is part of the db4o open source object database.
4
5 db4o is free software; you can redistribute it and/or modify it under
6 the terms of version 2 of the GNU General Public License as published
7 by the Free Software Foundation and as clarified by db4objects' GPL
8 interpretation policy, available at
9 http://www.db4o.com/about/company/legalpolicies/gplinterpretation/
10 Alternatively you can write to db4objects, Inc., 1900 S Norfolk Street,
11 Suite 350, San Mateo, CA 94403, USA.
12
13 db4o is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License along
19 with this program; if not, write to the Free Software Foundation, Inc.,
20 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
21 package com.db4o.test;
22
23 import com.db4o.*;
24 import com.db4o.ext.*;
25 import com.db4o.query.*;
26
27
28 public class DeleteDeep {
29     
30     public String JavaDoc name;
31     
32     public DeleteDeep child;
33     
34     public void storeOne(){
35         addNodes(10);
36         name = "root";
37     }
38     
39     private void addNodes(int count){
40         if(count > 0){
41             child = new DeleteDeep();
42             child.name = "" + count;
43             child.addNodes(count -1);
44         }
45     }
46     
47     public void test(){
48         ObjectContainer objectContainer = Test.objectContainer();
49         Query q = objectContainer.query();
50         q.constrain(DeleteDeep.class);
51         q.descend("name").constrain("root");
52         DeleteDeep root = (DeleteDeep)q.execute().next();
53         objectContainer.activate(root, Integer.MAX_VALUE);
54         
55         deleteDeep(objectContainer, root);
56         
57         objectContainer.commit();
58         Test.ensureOccurrences(DeleteDeep.class, 0);
59     }
60     
61     private void deleteDeep(ObjectContainer objectContainer, Object JavaDoc obj){
62         ObjectContainer allToDelete = ExtDb4o.openMemoryFile(null);
63         allToDelete.set(obj);
64         ObjectSet objectSet = allToDelete.get(null);
65         while(objectSet.hasNext()){
66             objectContainer.delete(objectSet.next());
67         }
68         allToDelete.close();
69     }
70     
71 }
72
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