1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/org/sonews/storage/AggregatedGroup.java Wed Jul 22 14:04:05 2009 +0200
1.3 @@ -0,0 +1,260 @@
1.4 +/*
1.5 + * SONEWS News Server
1.6 + * see AUTHORS for the list of contributors
1.7 + *
1.8 + * This program is free software: you can redistribute it and/or modify
1.9 + * it under the terms of the GNU General Public License as published by
1.10 + * the Free Software Foundation, either version 3 of the License, or
1.11 + * (at your option) any later version.
1.12 + *
1.13 + * This program is distributed in the hope that it will be useful,
1.14 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
1.15 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
1.16 + * GNU General Public License for more details.
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License
1.19 + * along with this program. If not, see <http://www.gnu.org/licenses/>.
1.20 + */
1.21 +
1.22 +package org.sonews.storage;
1.23 +
1.24 +import java.util.ArrayList;
1.25 +import java.util.Collections;
1.26 +import java.util.List;
1.27 +import org.sonews.util.Pair;
1.28 +
1.29 +/**
1.30 + * An aggregated group is a group consisting of several "real" group.
1.31 + * @author Christian Lins
1.32 + * @since sonews/1.0
1.33 + */
1.34 +class AggregatedGroup extends Channel
1.35 +{
1.36 +
1.37 + static class GroupElement
1.38 + {
1.39 + private Group group;
1.40 + private long offsetStart, offsetEnd;
1.41 +
1.42 + public GroupElement(Group group, long offsetStart, long offsetEnd)
1.43 + {
1.44 + this.group = group;
1.45 + this.offsetEnd = offsetEnd;
1.46 + this.offsetStart = offsetStart;
1.47 + }
1.48 + }
1.49 +
1.50 + public static List<Channel> getAll()
1.51 + {
1.52 + List<Channel> all = new ArrayList<Channel>();
1.53 + all.add(getByName("agg.test"));
1.54 + return all;
1.55 + }
1.56 +
1.57 + public static AggregatedGroup getByName(String name)
1.58 + {
1.59 + if("agg.test".equals(name))
1.60 + {
1.61 + AggregatedGroup agroup = new AggregatedGroup(name);
1.62 + agroup.addGroup(Group.getByName("agg.test0"), 0, 1000);
1.63 + agroup.addGroup(Group.getByName("agg.test1"), 2000, 4000);
1.64 + return agroup;
1.65 + }
1.66 + else
1.67 + return null;
1.68 + }
1.69 +
1.70 + private GroupElement[] groups = new GroupElement[2];
1.71 + private String name;
1.72 +
1.73 + public AggregatedGroup(String name)
1.74 + {
1.75 + this.name = name;
1.76 + }
1.77 +
1.78 + private long aggIdxToIdx(long aggIdx)
1.79 + throws StorageBackendException
1.80 + {
1.81 + assert groups != null && groups.length == 2;
1.82 + assert groups[0] != null;
1.83 + assert groups[1] != null;
1.84 +
1.85 + // Search in indices of group one
1.86 + List<Long> idxs0 = groups[0].group.getArticleNumbers();
1.87 + Collections.sort(idxs0);
1.88 + for(long idx : idxs0)
1.89 + {
1.90 + if(idx == aggIdx)
1.91 + {
1.92 + return idx;
1.93 + }
1.94 + }
1.95 +
1.96 + // Given aggIdx must be an index of group two
1.97 + List<Long> idxs1 = groups[1].group.getArticleNumbers();
1.98 + return 0;
1.99 + }
1.100 +
1.101 + private long idxToAggIdx(long idx)
1.102 + {
1.103 + return 0;
1.104 + }
1.105 +
1.106 + /**
1.107 + * Adds the given group to this aggregated set.
1.108 + * @param group
1.109 + * @param offsetStart Lower limit for the article ids range
1.110 + */
1.111 + public void addGroup(Group group, long offsetStart, long offsetEnd)
1.112 + {
1.113 + this.groups[groups[0] == null ? 0 : 1]
1.114 + = new GroupElement(group, offsetStart, offsetEnd);
1.115 + }
1.116 +
1.117 + @Override
1.118 + public Article getArticle(long idx)
1.119 + throws StorageBackendException
1.120 + {
1.121 + Article article = null;
1.122 +
1.123 + for(GroupElement groupEl : groups)
1.124 + {
1.125 + if(groupEl.offsetStart <= idx && groupEl.offsetEnd >= idx)
1.126 + {
1.127 + article = groupEl.group.getArticle(idx - groupEl.offsetStart);
1.128 + break;
1.129 + }
1.130 + }
1.131 +
1.132 + return article;
1.133 + }
1.134 +
1.135 + @Override
1.136 + public List<Pair<Long, ArticleHead>> getArticleHeads(
1.137 + final long first, final long last)
1.138 + throws StorageBackendException
1.139 + {
1.140 + List<Pair<Long, ArticleHead>> heads = new ArrayList<Pair<Long, ArticleHead>>();
1.141 +
1.142 + for(GroupElement groupEl : groups)
1.143 + {
1.144 + List<Pair<Long, ArticleHead>> partHeads = new ArrayList<Pair<Long, ArticleHead>>();
1.145 + if(groupEl.offsetStart <= first && groupEl.offsetEnd >= first)
1.146 + {
1.147 + long end = Math.min(groupEl.offsetEnd, last);
1.148 + partHeads = groupEl.group.getArticleHeads
1.149 + (first - groupEl.offsetStart, end - groupEl.offsetStart);
1.150 + }
1.151 + else if(groupEl.offsetStart <= last && groupEl.offsetEnd >= last)
1.152 + {
1.153 + long start = Math.max(groupEl.offsetStart, first);
1.154 + partHeads = groupEl.group.getArticleHeads
1.155 + (start - groupEl.offsetStart, last - groupEl.offsetStart);
1.156 + }
1.157 +
1.158 + for(Pair<Long, ArticleHead> partHead : partHeads)
1.159 + {
1.160 + heads.add(new Pair<Long, ArticleHead>(
1.161 + partHead.getA() + groupEl.offsetStart, partHead.getB()));
1.162 + }
1.163 + }
1.164 +
1.165 + return heads;
1.166 + }
1.167 +
1.168 + @Override
1.169 + public List<Long> getArticleNumbers()
1.170 + throws StorageBackendException
1.171 + {
1.172 + List<Long> articleNumbers = new ArrayList<Long>();
1.173 +
1.174 + for(GroupElement groupEl : groups)
1.175 + {
1.176 + List<Long> partNums = groupEl.group.getArticleNumbers();
1.177 + for(Long partNum : partNums)
1.178 + {
1.179 + articleNumbers.add(partNum + groupEl.offsetStart);
1.180 + }
1.181 + }
1.182 +
1.183 + return articleNumbers;
1.184 + }
1.185 +
1.186 + @Override
1.187 + public long getIndexOf(Article art)
1.188 + throws StorageBackendException
1.189 + {
1.190 + for(GroupElement groupEl : groups)
1.191 + {
1.192 + long idx = groupEl.group.getIndexOf(art);
1.193 + if(idx > 0)
1.194 + {
1.195 + return idx;
1.196 + }
1.197 + }
1.198 + return -1;
1.199 + }
1.200 +
1.201 + public long getInternalID()
1.202 + {
1.203 + return -1;
1.204 + }
1.205 +
1.206 + @Override
1.207 + public String getName()
1.208 + {
1.209 + return this.name;
1.210 + }
1.211 +
1.212 + @Override
1.213 + public long getFirstArticleNumber()
1.214 + throws StorageBackendException
1.215 + {
1.216 + long first = Long.MAX_VALUE;
1.217 +
1.218 + for(GroupElement groupEl : groups)
1.219 + {
1.220 + first = Math.min(first, groupEl.group.getFirstArticleNumber() + groupEl.offsetStart);
1.221 + }
1.222 +
1.223 + return first;
1.224 + }
1.225 +
1.226 + @Override
1.227 + public long getLastArticleNumber()
1.228 + throws StorageBackendException
1.229 + {
1.230 + long last = 1;
1.231 +
1.232 + for(GroupElement groupEl : groups)
1.233 + {
1.234 + last = Math.max(last, groupEl.group.getLastArticleNumber() + groupEl.offsetStart);
1.235 + }
1.236 +
1.237 + return last + getPostingsCount(); // This is a hack
1.238 + }
1.239 +
1.240 + public long getPostingsCount()
1.241 + throws StorageBackendException
1.242 + {
1.243 + long postings = 0;
1.244 +
1.245 + for(GroupElement groupEl : groups)
1.246 + {
1.247 + postings += groupEl.group.getPostingsCount();
1.248 + }
1.249 +
1.250 + return postings;
1.251 + }
1.252 +
1.253 + public boolean isDeleted()
1.254 + {
1.255 + return false;
1.256 + }
1.257 +
1.258 + public boolean isWriteable()
1.259 + {
1.260 + return false;
1.261 + }
1.262 +
1.263 +}