org/sonews/storage/Channel.java
author cli
Fri Aug 21 17:33:15 2009 +0200 (2009-08-21)
changeset 18 7e527fdf0fa8
parent 3 2fdc9cc89502
child 31 087ef6fe6a1a
permissions -rw-r--r--
Fix for #549.
     1 /*
     2  *   SONEWS News Server
     3  *   see AUTHORS for the list of contributors
     4  *
     5  *   This program is free software: you can redistribute it and/or modify
     6  *   it under the terms of the GNU General Public License as published by
     7  *   the Free Software Foundation, either version 3 of the License, or
     8  *   (at your option) any later version.
     9  *
    10  *   This program is distributed in the hope that it will be useful,
    11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
    12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    13  *   GNU General Public License for more details.
    14  *
    15  *   You should have received a copy of the GNU General Public License
    16  *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
    17  */
    18 
    19 package org.sonews.storage;
    20 
    21 import java.util.ArrayList;
    22 import java.util.List;
    23 import org.sonews.util.Pair;
    24 
    25 /**
    26  * A logical communication Channel is the a generic structural element for sets
    27  * of messages; e.g. a Newsgroup for a set of Articles.
    28  * A Channel can either be a real set of messages or an aggregated set of
    29  * several subsets.
    30  * @author Christian Lins
    31  * @since sonews/1.0
    32  */
    33 public abstract class Channel
    34 {
    35 
    36   /**
    37    * If this flag is set the Group is no real newsgroup but a mailing list
    38    * mirror. In that case every posting and receiving mails must go through
    39    * the mailing list gateway.
    40    */
    41   public static final int MAILINGLIST = 0x1;
    42 
    43   /**
    44    * If this flag is set the Group is marked as readonly and the posting
    45    * is prohibited. This can be useful for groups that are synced only in
    46    * one direction.
    47    */
    48   public static final int READONLY    = 0x2;
    49 
    50   /**
    51    * If this flag is set the Group is marked as deleted and must not occur
    52    * in any output. The deletion is done lazily by a low priority daemon.
    53    */
    54   public static final int DELETED     = 0x80;
    55 
    56   public static List<Channel> getAll()
    57   {
    58     List<Channel> all = new ArrayList<Channel>();
    59 
    60     /*List<Channel> agroups = AggregatedGroup.getAll();
    61     if(agroups != null)
    62     {
    63       all.addAll(agroups);
    64     }*/
    65 
    66     List<Channel> groups = Group.getAll();
    67     if(groups != null)
    68     {
    69       all.addAll(groups);
    70     }
    71 
    72     return all;
    73   }
    74 
    75   public static Channel getByName(String name)
    76   {
    77     return Group.getByName(name);
    78   }
    79 
    80   public abstract Article getArticle(long idx)
    81     throws StorageBackendException;
    82 
    83   public abstract List<Pair<Long, ArticleHead>> getArticleHeads(
    84     final long first, final long last)
    85     throws StorageBackendException;
    86 
    87   public abstract List<Long> getArticleNumbers()
    88     throws StorageBackendException;
    89 
    90   public abstract long getFirstArticleNumber()
    91     throws StorageBackendException;
    92 
    93   public abstract long getIndexOf(Article art)
    94     throws StorageBackendException;
    95 
    96   public abstract long getInternalID();
    97 
    98   public abstract long getLastArticleNumber()
    99     throws StorageBackendException;
   100 
   101   public abstract String getName();
   102   
   103   public abstract long getPostingsCount()
   104     throws StorageBackendException;
   105 
   106   public abstract boolean isDeleted();
   107 
   108   public abstract boolean isWriteable();
   109 
   110 }