Mir goes GPL

[mir.git] / source / mircoders / storage / DatabaseTopics.java

diff --git a/source/mircoders/storage/DatabaseTopics.java b/source/mircoders/storage/DatabaseTopics.java
index 5804b88..51deeb7 100755 (executable)
--- a/source/mircoders/storage/DatabaseTopics.java
+++ b/source/mircoders/storage/DatabaseTopics.java
@@ -1,3 +1,34 @@
+/*
+ * Copyright (C) 2001, 2002  The Mir-coders group
+ *
+ * This file is part of Mir.
+ *
+ * Mir is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Mir is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Mir; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * In addition, as a special exception, The Mir-coders gives permission to link
+ * the code of this program with the com.oreilly.servlet library, any library
+ * licensed under the Apache Software License, The Sun (tm) Java Advanced
+ * Imaging library (JAI), The Sun JIMI library (or with modified versions of
+ * the above that use the same license as the above), and distribute linked
+ * combinations including the two.  You must obey the GNU General Public
+ * License in all respects for all of the code used other than the above
+ * mentioned libraries.  If you modify this file, you may extend this exception
+ * to your version of the file, but you are not obligated to do so.  If you do
+ * not wish to do so, delete this exception statement from your version.
+ */
+
 package mircoders.storage;
 
 import java.lang.*;
@@ -19,34 +50,38 @@ import mir.misc.*;
 
 public class DatabaseTopics extends Database implements StorageObject{
 
-       private static DatabaseTopics instance;
+  private static DatabaseTopics instance;
 
-       public static DatabaseTopics getInstance() throws StorageObjectException {
-                       if (instance == null) {
-               instance = new DatabaseTopics();
-               instance.myselfDatabase = instance;
-                       }
-               return instance;
-       }
+  // the following *has* to be sychronized cause this static method
+  // could get preemted and we could end up with 2 instances of DatabaseFoo..
+  // see the "Singletons with needles and thread" article at JavaWorld -mh
+  public synchronized static DatabaseTopics getInstance() 
+    throws StorageObjectException {
+      if (instance == null) {
+    instance = new DatabaseTopics();
+    instance.myselfDatabase = instance;
+      }
+    return instance;
+  }
 
-       private DatabaseTopics() throws StorageObjectException
-       {
+  private DatabaseTopics() throws StorageObjectException
+  {
           super();
-                       this.cache = new HashMap();
-                       this.hasTimestamp = false;
-                       this.theTable="topic";
-                       try {
-               this.theEntityClass = Class.forName("mircoders.entity.EntityTopics");
-                       }
-                       catch (Exception e) {
-               throw new StorageObjectException(e.toString());
-                       }
-
-       }
-
-       public SimpleList getPopupData() {
-               return getPopupData("title",true);
-       }
+      //this.cache = new DatabaseCache(20);
+      this.hasTimestamp = false;
+      this.theTable="topic";
+      try {
+    this.theEntityClass = Class.forName("mircoders.entity.EntityTopics");
+      }
+      catch (Exception e) {
+    throw new StorageObjectException(e.toString());
+      }
+
+  }
+
+  public SimpleList getPopupData() throws StorageObjectException {
+    return getPopupData("title",true);
+  }