aboutsummaryrefslogtreecommitdiffstats
path: root/src/net/java/sip/communicator/impl/configuration/JdbcConfigService.java
blob: 7ba362e527cbf016930ea57a4c37ec01b67a46aa (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
/*
 * Jitsi, the OpenSource Java VoIP and Instant Messaging client.
 *
 * Copyright @ 2015 Atlassian Pty Ltd
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.java.sip.communicator.impl.configuration;

import java.beans.*;
import java.io.*;
import java.sql.*;
import java.sql.Statement;
import java.util.*;
import java.util.regex.Pattern;

import org.jitsi.service.configuration.*;
import org.jitsi.service.fileaccess.*;
import org.jitsi.util.*;

import com.google.common.collect.*;

/**
 * Implementation of the {@link ConfigurationService} based on JDBC.
 * 
 * @author Ingo Bauersachs
 */
public final class JdbcConfigService
    implements ConfigurationService
{
    /**
     * The <tt>Logger</tt> used by this class.
     */
    private final Logger logger
        = Logger.getLogger(JdbcConfigService.class);

    /**
     * Name of the file containing default properties.
     */
    private static final String DEFAULT_PROPS_FILE_NAME
        = "jitsi-defaults.properties";

    /**
     * Name of the file containing overrides (possibly set by the distributor)
     * for any of the default properties.
     */
    private static final String DEFAULT_OVERRIDES_PROPS_FILE_NAME
        = "jitsi-default-overrides.properties";

    /**
     * A set of immutable properties deployed with the application during
     * install time. The properties in this file will be impossible to override
     * and attempts to do so will simply be ignored.
     * @see #defaultProperties
     */
    private Map<String, String> immutableDefaultProperties
        = new HashMap<String, String>();

    /**
     * A set of properties deployed with the application during install time.
     * Contrary to the properties in {@link #immutableDefaultProperties} the
     * ones in this map can be overridden with call to the
     * <tt>setProperty()</tt> methods. Still, re-setting one of these properties
     * to <tt>null</tt> would cause for its initial value to be restored.
     */
    private Map<String, String> defaultProperties
        = new HashMap<String, String>();

    /**
     * Registered property change listeners that may veto a change.
     */
    private SetMultimap<String, ConfigVetoableChangeListener> vetoListeners
        = HashMultimap.create();

    /**
     * Registered property change listeners.
     */
    private SetMultimap<String, PropertyChangeListener> listeners
        = HashMultimap.create();

    /**
     * Connection to the JDBC database.
     */
    private Connection connection;

    // SQL statements for queries against the database
    private PreparedStatement selectExact;
    private PreparedStatement selectLike;
    private PreparedStatement selectAll;
    private PreparedStatement insertOrUpdate;
    private PreparedStatement delete;

    /**
     * Reference to the {@link FileAccessService}.
     */
    private FileAccessService fas; 

    /**
     * Creates a new instance of this class.
     * @param fas Reference to the {@link FileAccessService}.
     * @throws Exception
     */
    public JdbcConfigService(FileAccessService fas) throws Exception
    {
        this.fas = fas;
        File dataFile = fas.getPrivatePersistentFile(
            "props.hsql.script",
            FileCategory.PROFILE);
        File oldProps = fas.getPrivatePersistentFile(
            "sip-communicator.properties",
            FileCategory.PROFILE);

        // if the file for the current database does not exist yet but
        // the previous properties-based file is there, migrate it
        boolean migrate = false;
        if (!dataFile.exists() && oldProps.exists())
        {
            migrate = true;
        }

        // open the connection
        Class.forName("org.hsqldb.jdbc.JDBCDriver");
        checkConnection();

        // then do the actual migration
        if (migrate)
        {
            Properties p = new Properties();
            p.load(new FileInputStream(oldProps));

            this.connection.setAutoCommit(false);
            for (Map.Entry<Object, Object> e : p.entrySet())
            {
                this.setProperty(e.getKey().toString(), e.getValue(), false);
            }

            this.connection.commit();
            this.connection.setAutoCommit(true);
        }

        // and finally load the (mandatory) system properties
        loadDefaultProperties(DEFAULT_PROPS_FILE_NAME);
        loadDefaultProperties(DEFAULT_OVERRIDES_PROPS_FILE_NAME);
    }

    /**
     * Verifies that the connection to the database and all prepared statement
     * are valid.
     * 
     * @throws SQLException
     */
    private void checkConnection() throws SQLException
    {
        if (this.connection != null && this.connection.isValid(1))
        {
            try
            {
                PreparedStatement st = this.connection.prepareStatement(
                    "SELECT 1 FROM INFORMATION_SCHEMA.SYSTEM_USERS");
                if (st.execute())
                {
                    return;
                }
            }
            catch(Exception e)
            {
                this.connection = null;
                logger.error("Database connection is invalid, recreating", e);
            }
        }

        String filename;
        try
        {
            File f = fas.getPrivatePersistentFile(
                "props.hsql",
                FileCategory.PROFILE);
            filename = f.getAbsolutePath();
        }
        catch (Exception e)
        {
            throw new SQLException(e);
        }

        this.connection = DriverManager.getConnection(
            "jdbc:hsqldb:file:"
            + filename
            + ";shutdown=true;hsqldb.write_delay=false;"
            + "hsqldb.write_delay_millis=0");
        Statement st = this.connection.createStatement();
        st.executeUpdate(
            "CREATE TABLE IF NOT EXISTS Props ("
            + "k LONGVARCHAR UNIQUE, v LONGVARCHAR"
            + ")");

        this.selectExact = this.connection.prepareStatement(
            "SELECT v FROM Props WHERE k=?");
        this.selectLike = this.connection.prepareStatement(
            "SELECT k, v FROM Props WHERE k LIKE ?");
        this.selectAll = this.connection.prepareStatement(
            "SELECT k, v FROM Props");
        this.insertOrUpdate = this.connection.prepareStatement(
            "MERGE INTO Props"
                + " USING (VALUES(?,?)) AS i(k,v) ON Props.k = i.k"
                + " WHEN MATCHED THEN UPDATE SET Props.v = i.v"
                + " WHEN NOT MATCHED THEN INSERT (k, v) VALUES (i.k, i.v)");
        this.delete = this.connection.prepareStatement(
            "DELETE FROM Props WHERE k=?");
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#setProperty(java
     * .lang.String, java.lang.Object)
     */
    @Override
    public synchronized void setProperty(String propertyName, Object property)
    {
        this.setProperty(propertyName, property, false);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#setProperty(java
     * .lang.String, java.lang.Object, boolean)
     */
    @Override
    public synchronized void setProperty(String propertyName, Object property,
        boolean isSystem)
    {
        // a property with the same name as an existing system property cannot
        // be set, so mark it as a system property
        if (!isSystem && System.getProperty(propertyName) != null)
        {
            isSystem = true;
        }

        if (isSystem)
        {
            if (property == null)
            {
                System.clearProperty(propertyName);
                return;
            }

            System.setProperty(propertyName, property.toString());
        }
        else
        {
            if (immutableDefaultProperties.containsKey(propertyName))
            {
                return;
            }

            try
            {
                this.checkConnection();
                Object oldValue = this.getProperty(propertyName);
                this.fireVetoableChange(propertyName, oldValue, property);
                if (property == null)
                {
                    this.delete.setString(1, propertyName);
                    this.delete.execute();
                }
                else
                {
                    this.insertOrUpdate.setString(1, propertyName);
                    this.insertOrUpdate.setString(2, property.toString());
                    this.insertOrUpdate.execute();
                }

                this.fireChange(propertyName, oldValue, property);
            }
            catch (SQLException e)
            {
                throw new RuntimeException(e);
            }
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#setProperties(java
     * .util.Map)
     */
    @Override
    public synchronized void setProperties(Map<String, Object> properties)
    {
        try
        {
            checkConnection();
            this.connection.setAutoCommit(false);
            for (Map.Entry<String, Object> e : properties.entrySet())
            {
                this.setProperty(e.getKey(), e.getValue(), false);
            }

            this.connection.commit();
            this.connection.setAutoCommit(true);
        }
        catch (SQLException e1)
        {
            throw new RuntimeException(e1);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getProperty(java
     * .lang.String)
     */
    @Override
    public synchronized Object getProperty(String propertyName)
    {
        Object value = immutableDefaultProperties.get(propertyName);
        if (value != null)
        {
            return value;
        }

        try
        {
            this.checkConnection();
            this.selectExact.setString(1, propertyName);
            ResultSet q = this.selectExact.executeQuery();
            if (q.next())
            {
                value = q.getString(1);
            }
        }
        catch (SQLException e)
        {
            logger.error(e);
            throw new RuntimeException(e);
        }

        if (value != null)
        {
            return value;
        }

        value = defaultProperties.get(propertyName);
        if (value != null)
        {
            return value;
        }

        return System.getProperty(propertyName);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#removeProperty(java
     * .lang.String)
     */
    @Override
    public synchronized void removeProperty(String propertyName)
    {
        //remove all properties
        for (String child : this.getPropertyNamesByPrefix(propertyName, false))
        {
            this.setProperty(child, null, false);
        }

        this.setProperty(propertyName, null, false);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getAllPropertyNames
     * ()
     */
    @Override
    public List<String> getAllPropertyNames()
    {
        List<String> data = new ArrayList<String>(
            immutableDefaultProperties.keySet());
        data.addAll(defaultProperties.keySet());
        try
        {
            this.checkConnection();
            ResultSet q = this.selectAll.executeQuery();
            while (q.next())
            {
                data.add(q.getString(1));
            }
        }
        catch (SQLException e)
        {
            logger.error(e);
            throw new RuntimeException(e);
        }

        return data;
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService
     * #getPropertyNamesByPrefix(java.lang.String, boolean)
     */
    @Override
    public List<String> getPropertyNamesByPrefix(String prefix,
        boolean exactPrefixMatch)
    {
        try
        {
            List<String> resultSet = new ArrayList<String>(50);
            this.checkConnection();
            this.selectLike.setString(1, prefix + "%");
            ResultSet q = this.selectLike.executeQuery();
            while (q.next())
            {
                String key = q.getString(1);

                if(exactPrefixMatch)
                {
                    int ix = key.lastIndexOf('.');
                    if(ix == -1)
                    {
                        continue;
                    }

                    String keyPrefix = key.substring(0, ix);

                    if(prefix.equals(keyPrefix))
                    {
                        resultSet.add(key);
                    }
                }
                else
                {
                    if(key.startsWith(prefix))
                    {
                        resultSet.add(key);
                    }
                }
            }

            return resultSet;
        }
        catch (SQLException e)
        {
            throw new RuntimeException(e);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService
     * #getPropertyNamesBySuffix(java.lang.String)
     */
    @Override
    public List<String> getPropertyNamesBySuffix(String suffix)
    {
        try
        {
            List<String> resultKeySet = new ArrayList<String>(20);
            this.checkConnection();
            this.selectLike.setString(1, "%" + suffix);
            ResultSet q = this.selectLike.executeQuery();
            while (q.next())
            {
                String key = q.getString(1);
                int ix = key.lastIndexOf('.');
                if (ix != -1 && suffix.equals(key.substring(ix + 1)))
                    resultKeySet.add(key);
            }

            return resultKeySet;
        }
        catch (SQLException e)
        {
            throw new RuntimeException(e);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getString(java.lang
     * .String)
     */
    @Override
    public String getString(String propertyName)
    {
        String value = (String)this.getProperty(propertyName);
        if (value != null)
        {
            value = value.trim();
            if (value.length() == 0)
            {
                return null;
            }
        }

        return value;
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getString(java.lang
     * .String, java.lang.String)
     */
    @Override
    public String getString(String propertyName, String defaultValue)
    {
        String value = this.getString(propertyName);
        if (value == null)
        {
            return defaultValue;
        }

        return value;
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getBoolean(java.
     * lang.String, boolean)
     */
    @Override
    public boolean getBoolean(String propertyName, boolean defaultValue)
    {
        Object value = this.getProperty(propertyName);
        if (value == null)
        {
            return defaultValue;
        }

        return Boolean.parseBoolean(value.toString());
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getInt(java.lang
     * .String, int)
     */
    @Override
    public int getInt(String propertyName, int defaultValue)
    {
        Object value = this.getProperty(propertyName);
        if (value == null || "".equals(value.toString()))
        {
            return defaultValue;
        }

        try
        {
            return Integer.parseInt(value.toString());
        }
        catch (NumberFormatException ex)
        {
            logger.error(String.format(
                "'%s' for property %s not an integer, returning default (%s)",
                value, propertyName, defaultValue), ex);
            return defaultValue;
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getLong(java.lang
     * .String, long)
     */
    @Override
    public long getLong(String propertyName, long defaultValue)
    {
        Object value = this.getProperty(propertyName);
        if (value == null || "".equals(value.toString()))
        {
            return defaultValue;
        }

        try
        {
            return Long.parseLong(value.toString());
        }
        catch (NumberFormatException ex)
        {
            logger.error(String.format(
                "'%s' for property %s not a long, returning default (%s)",
                value, propertyName, defaultValue), ex);
            return defaultValue;
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * addPropertyChangeListener(java.beans.PropertyChangeListener)
     */
    @Override
    public void addPropertyChangeListener(PropertyChangeListener listener)
    {
        this.listeners.put(null, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * removePropertyChangeListener(java.beans.PropertyChangeListener)
     */
    @Override
    public void removePropertyChangeListener(PropertyChangeListener listener)
    {
        this.listeners.remove(null, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * addPropertyChangeListener(java.lang.String,
     * java.beans.PropertyChangeListener)
     */
    @Override
    public void addPropertyChangeListener(String propertyName,
        PropertyChangeListener listener)
    {
        this.listeners.put(propertyName, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * removePropertyChangeListener(java.lang.String,
     * java.beans.PropertyChangeListener)
     */
    @Override
    public void removePropertyChangeListener(String propertyName,
        PropertyChangeListener listener)
    {
        this.listeners.remove(propertyName, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * addVetoableChangeListener
     * (org.jitsi.service.configuration.ConfigVetoableChangeListener)
     */
    @Override
    public void addVetoableChangeListener(ConfigVetoableChangeListener listener)
    {
        this.vetoListeners.put(null, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * removeVetoableChangeListener
     * (org.jitsi.service.configuration.ConfigVetoableChangeListener)
     */
    @Override
    public void removeVetoableChangeListener(
        ConfigVetoableChangeListener listener)
    {
        this.vetoListeners.remove(null, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * addVetoableChangeListener(java.lang.String,
     * org.jitsi.service.configuration.ConfigVetoableChangeListener)
     */
    @Override
    public void addVetoableChangeListener(String propertyName,
        ConfigVetoableChangeListener listener)
    {
        this.vetoListeners.put(propertyName, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see org.jitsi.service.configuration.ConfigurationService#
     * removeVetoableChangeListener(java.lang.String,
     * org.jitsi.service.configuration.ConfigVetoableChangeListener)
     */
    @Override
    public void removeVetoableChangeListener(String propertyName,
        ConfigVetoableChangeListener listener)
    {
        this.vetoListeners.remove(propertyName, listener);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#storeConfiguration()
     */
    @Override
    public void storeConfiguration() throws IOException
    {
        try
        {
            this.connection.close();
        }
        catch (SQLException e)
        {
            logger.error(e);
        }
        finally
        {
            this.connection = null;
        }
    }

    /**
     * Does nothing. The database cannot be edited from the outside.
     */
    @Override
    public void reloadConfiguration() throws IOException
    {
        // nothing to do, the file cannot be edited outside
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#purgeStoredConfiguration
     * ()
     */
    @Override
    public void purgeStoredConfiguration()
    {
        try
        {
            this.checkConnection();
            Statement st = this.connection.createStatement();
            st.executeUpdate("TRUNCATE TABLE Props");
        }
        catch (SQLException e)
        {
            logger.error(e);
            throw new RuntimeException(e);
        }
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getScHomeDirName()
     */
    @Override
    public String getScHomeDirName()
    {
        return System.getProperty(PNAME_SC_HOME_DIR_NAME);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getScHomeDirLocation
     * ()
     */
    @Override
    public String getScHomeDirLocation()
    {
        return System.getProperty(PNAME_SC_HOME_DIR_LOCATION);
    }

    /*
     * (non-Javadoc)
     * 
     * @see
     * org.jitsi.service.configuration.ConfigurationService#getConfigurationFilename
     * ()
     */
    @Override
    public String getConfigurationFilename()
    {
        return "props.hsql.script";
    }

    /**
     * Loads the specified default properties maps from the Jitsi installation
     * directory. Typically this file is to be called for the default properties
     * and the admin overrides.
     * 
     * @param fileName the name of the file we need to load.
     */
    private void loadDefaultProperties(String fileName)
    {
        try
        {
            Properties fileProps = new Properties();

            InputStream fileStream;
            if(OSUtils.IS_ANDROID)
            {
                fileStream
                        = getClass().getClassLoader()
                                .getResourceAsStream(fileName);
            }
            else
            {
                fileStream = ClassLoader.getSystemResourceAsStream(fileName);
            }

            fileProps.load(fileStream);
            fileStream.close();

            // now get those properties and place them into the mutable and
            // immutable properties maps.
            for (Map.Entry<Object, Object> entry : fileProps.entrySet())
            {
                String name  = (String) entry.getKey();
                String value = (String) entry.getValue();

                if (   name == null
                    || value == null
                    || name.trim().length() == 0)
                {
                    continue;
                }

                if (name.startsWith("*"))
                {
                    name = name.substring(1);

                    if(name.trim().length() == 0)
                    {
                        continue;
                    }

                    //it seems that we have a valid default immutable property
                    immutableDefaultProperties.put(name, value);

                    //in case this is an override, make sure we remove previous
                    //definitions of this property
                    defaultProperties.remove(name);
                }
                else
                {
                    //this property is a regular, mutable default property.
                    defaultProperties.put(name, value);

                    //in case this is an override, make sure we remove previous
                    //definitions of this property
                    immutableDefaultProperties.remove(name);
                }
            }
        }
        catch (Exception ex)
        {
            //we can function without defaults so we are just logging those.
            logger.info("No defaults property file loaded: " + fileName
                + ". Not a problem.");

            if(logger.isDebugEnabled())
                logger.debug("load exception", ex);
        }
    }

    /**
     * Notify all listening objects about a prospective change.
     * 
     * @param propertyName The property that is going to change.
     * @param oldValue The previous value of the property (can be <tt>null</tt>)
     * @param newValue The new value of the property (can be <tt>null</tt>)
     */
    private void fireVetoableChange(String propertyName,
        Object oldValue, Object newValue)
    {
        PropertyChangeEvent evt = new PropertyChangeEvent(
            this,
            propertyName,
            oldValue,
            newValue);

        for (ConfigVetoableChangeListener l : vetoListeners.get(propertyName))
        {
            l.vetoableChange(evt);
        }

        for (ConfigVetoableChangeListener l : vetoListeners.get(null))
        {
            l.vetoableChange(evt);
        }
    }

    /**
     * Notify all listeners that a property has changed.
     * 
     * @param propertyName The property that has just changed.
     * @param oldValue The previous value of the property (can be <tt>null</tt>)
     * @param newValue The new value of the property (can be <tt>null</tt>)
     */
    private void fireChange(String propertyName,
        Object oldValue, Object newValue)
    {
        PropertyChangeEvent evt = new PropertyChangeEvent(
            this,
            propertyName,
            oldValue,
            newValue);

        for (PropertyChangeListener l : listeners.get(propertyName))
        {
            l.propertyChange(evt);
        }

        for (PropertyChangeListener l : listeners.get(null))
        {
            l.propertyChange(evt);
        }
    }

    @Override
    public void logConfigurationProperties(String excludePattern)
    {
        if (!logger.isInfoEnabled())
            return;

        Pattern exclusion = null;
        if (!StringUtils.isNullOrEmpty(excludePattern))
        {
            exclusion = Pattern.compile(
                excludePattern, Pattern.CASE_INSENSITIVE);
        }

        for (String p : getAllPropertyNames())
        {
            Object v = getProperty(p);

            // Not sure if this can happen, but just in case...
            if (v == null)
                continue;

            if (exclusion != null && exclusion.matcher(p).find())
            {
                v = "**********";
            }

            logger.info(p + "=" + v);
        }
    }
}