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
.internal
.tmf
.core
.statesystem
.HistoryBuilder
;
19 import org
.eclipse
.linuxtools
.internal
.tmf
.core
.statesystem
.IStateHistoryBackend
;
20 import org
.eclipse
.linuxtools
.internal
.tmf
.core
.statesystem
.historytree
.HistoryTreeBackend
;
21 import org
.eclipse
.linuxtools
.internal
.tmf
.core
.statesystem
.historytree
.ThreadedHistoryTreeBackend
;
22 import org
.eclipse
.linuxtools
.tmf
.core
.component
.TmfComponent
;
23 import org
.eclipse
.linuxtools
.tmf
.core
.exceptions
.TmfTraceException
;
26 * This abstract manager class handles loading or creating state history files
27 * for use in TMF's generic state system.
30 * @author Alexandre Montplaisir
32 public abstract class StateSystemManager
extends TmfComponent
{
34 /** Size of the blocking queue to use when building a state history */
35 private final static int QUEUE_SIZE
= 10000;
38 * Load the history file matching the target trace. If the file already
39 * exists, it will be opened directly. If not, it will be created from
40 * scratch. In the case the history has to be built, it's possible to block
41 * the calling thread until construction is complete.
44 * The target name of the history file we want to use. If it
45 * exists it will be opened. If it doesn't, a new file will be
46 * created with this name/path.
48 * The IStateChangeInput to use for building the history file. It
49 * may be required even if we are opening an already-existing
50 * history (ie, for partial histories).
51 * @param buildManually
52 * If false, the construction will wait for a signal before
53 * starting. If true, it will build everything right now and
54 * block the caller. It has no effect if the file already exists.
55 * @return A IStateSystemQuerier handler to the state system, with which you
56 * can then run queries on the history.
57 * @throws TmfTraceException
58 * If there was a problem reading or writing one of the files.
59 * See the contents of this exception for more info.
61 public static IStateSystemQuerier
loadStateHistory(File htFile
,
62 IStateChangeInput htInput
, boolean buildManually
)
63 throws TmfTraceException
{
64 IStateSystemQuerier ss
;
65 IStateHistoryBackend htBackend
;
67 /* If the target file already exists, do not rebuild it uselessly */
68 // TODO for now we assume it's complete. Might be a good idea to check
69 // at least if its range matches the trace's range.
70 if (htFile
.exists()) {
71 /* Load an existing history */
73 htBackend
= new HistoryTreeBackend(htFile
);
74 ss
= HistoryBuilder
.openExistingHistory(htBackend
);
76 } catch (IOException e
) {
78 * There was an error opening the existing file. Perhaps it was
79 * corrupted, perhaps it's an old version? We'll just
80 * fall-through and try to build a new one from scratch instead.
85 /* Create a new state history from scratch */
86 HistoryBuilder builder
;
88 if (htInput
== null) {
92 htBackend
= new ThreadedHistoryTreeBackend(htFile
,
93 htInput
.getStartTime(), QUEUE_SIZE
);
94 builder
= new HistoryBuilder(htInput
, htBackend
, buildManually
);
95 } catch (IOException e
) {
97 * If it fails here however, it means there was a problem writing to
98 * the disk, so throw a real exception this time.
100 throw new TmfTraceException(e
.toString(), e
);
102 return builder
.getStateSystemQuerier();