1 /*******************************************************************************
2 * Copyright (c) 2012 Ericsson
3 * Copyright (c) 2010, 2011 École Polytechnique de Montréal
4 * Copyright (c) 2010, 2011 Alexandre Montplaisir <alexandre.montplaisir@gmail.com>
6 * All rights reserved. This program and the accompanying materials are
7 * made available under the terms of the Eclipse Public License v1.0 which
8 * accompanies this distribution, and is available at
9 * http://www.eclipse.org/legal/epl-v10.html
11 *******************************************************************************/
13 package org
.eclipse
.linuxtools
.tmf
.core
.statesystem
;
16 import java
.io
.IOException
;
18 import org
.eclipse
.linuxtools
.tmf
.core
.component
.TmfComponent
;
19 import org
.eclipse
.linuxtools
.tmf
.core
.exceptions
.TmfTraceException
;
20 import org
.eclipse
.linuxtools
.tmf
.core
.statesystem
.backend
.historytree
.HistoryTreeBackend
;
21 import org
.eclipse
.linuxtools
.tmf
.core
.statesystem
.backend
.historytree
.ThreadedHistoryTreeBackend
;
24 * This abstract manager class handles loading or creating state history files
25 * for use in TMF's generic state system.
30 public abstract class StateSystemManager
extends TmfComponent
{
32 /** Size of the blocking queue to use when building a state history */
33 private final static int QUEUE_SIZE
= 10000;
36 * Load the history file matching the target trace. If the file already
37 * exists, it will be opened directly. If not, it will be created from
38 * scratch. In the case the history has to be built, it's possible to block
39 * the calling thread until construction is complete.
42 * The target name of the history file we want to use. If it
43 * exists it will be opened. If it doesn't, a new file will be
44 * created with this name/path.
46 * The IStateChangeInput to use for building the history file. It
47 * may be required even if we are opening an already-existing
48 * history (ie, for partial histories).
49 * @param waitForCompletion
50 * Should we block the calling thread until the construction is
51 * complete? It has no effect if the file already exists.
52 * @return A IStateSystemQuerier handler to the state system, with which you
53 * can then run queries on the history.
54 * @throws TmfTraceException
56 public static IStateSystemQuerier
loadStateHistory(File htFile
,
57 IStateChangeInput htInput
) throws TmfTraceException
{
58 IStateSystemQuerier ss
;
59 IStateHistoryBackend htBackend
;
61 /* If the target file already exists, do not rebuild it uselessly */
62 // TODO for now we assume it's complete. Might be a good idea to check
63 // at least if its range matches the trace's range.
64 if (htFile
.exists()) {
65 /* Load an existing history */
67 htBackend
= new HistoryTreeBackend(htFile
);
68 ss
= HistoryBuilder
.openExistingHistory(htBackend
);
70 } catch (IOException e
) {
72 * There was an error opening the existing file. Perhaps it was
73 * corrupted, perhaps it's an old version? We'll just
74 * fall-through and try to build a new one from scratch instead.
79 /* Create a new state history from scratch */
80 HistoryBuilder builder
;
81 if (htInput
== null) {
85 htBackend
= new ThreadedHistoryTreeBackend(htFile
,
86 htInput
.getStartTime(), QUEUE_SIZE
);
87 builder
= new HistoryBuilder(htInput
, htBackend
);
88 builder
.run(); //FIXME
89 } catch (IOException e
) {
91 * If it fails here however, it means there was a problem writing
92 * to the disk, so throw a real exception this time.
94 throw new TmfTraceException(e
.toString(), e
);
96 return builder
.getStateSystemQuerier();