diff -r 9f0b95aafaa3 -r ed84c8bdd87b src/org/sonews/storage/Channel.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/org/sonews/storage/Channel.java	Sun Aug 29 17:28:58 2010 +0200
@@ -0,0 +1,111 @@
+/*
+ *   SONEWS News Server
+ *   see AUTHORS for the list of contributors
+ *
+ *   This program 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 3 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.sonews.storage;
+
+import java.util.ArrayList;
+import java.util.List;
+import org.sonews.util.Pair;
+
+/**
+ * A logical communication Channel is the a generic structural element for sets
+ * of messages; e.g. a Newsgroup for a set of Articles.
+ * A Channel can either be a real set of messages or an aggregated set of
+ * several subsets.
+ * @author Christian Lins
+ * @since sonews/1.0
+ */
+public abstract class Channel
+{
+
+  /**
+   * If this flag is set the Group is no real newsgroup but a mailing list
+   * mirror. In that case every posting and receiving mails must go through
+   * the mailing list gateway.
+   */
+  public static final int MAILINGLIST = 0x1;
+
+  /**
+   * If this flag is set the Group is marked as readonly and the posting
+   * is prohibited. This can be useful for groups that are synced only in
+   * one direction.
+   */
+  public static final int READONLY    = 0x2;
+
+  /**
+   * If this flag is set the Group is marked as deleted and must not occur
+   * in any output. The deletion is done lazily by a low priority daemon.
+   */
+  public static final int DELETED     = 0x80;
+
+  public static List<Channel> getAll()
+  {
+    List<Channel> all = new ArrayList<Channel>();
+
+    /*List<Channel> agroups = AggregatedGroup.getAll();
+    if(agroups != null)
+    {
+      all.addAll(agroups);
+    }*/
+
+    List<Channel> groups = Group.getAll();
+    if(groups != null)
+    {
+      all.addAll(groups);
+    }
+
+    return all;
+  }
+
+  public static Channel getByName(String name)
+    throws StorageBackendException
+  {
+    return StorageManager.current().getGroup(name);
+  }
+
+  public abstract Article getArticle(long idx)
+    throws StorageBackendException;
+
+  public abstract List<Pair<Long, ArticleHead>> getArticleHeads(
+    final long first, final long last)
+    throws StorageBackendException;
+
+  public abstract List<Long> getArticleNumbers()
+    throws StorageBackendException;
+
+  public abstract long getFirstArticleNumber()
+    throws StorageBackendException;
+
+  public abstract long getIndexOf(Article art)
+    throws StorageBackendException;
+
+  public abstract long getInternalID();
+
+  public abstract long getLastArticleNumber()
+    throws StorageBackendException;
+
+  public abstract String getName();
+  
+  public abstract long getPostingsCount()
+    throws StorageBackendException;
+
+  public abstract boolean isDeleted();
+
+  public abstract boolean isWriteable();
+
+}