1  /*
     2   * Licensed to the Apache Software Foundation (ASF) under one or more
     3   *  contributor license agreements.  The ASF licenses this file to You
     4   * under the Apache License, Version 2.0 (the "License"); you may not
     5   * use this file except in compliance with the License.
     6   * You may obtain a copy of the License at
     7   *
     8   *     http://www.apache.org/licenses/LICENSE-2.0
     9   *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.  For additional information regarding
    15   * copyright in this work, please see the NOTICE file in the top level
    16   * directory of this distribution.
    17   */
    18  
    19  package org.apache.roller.weblogger.ui.rendering.pagers;
    20  
    21  import java.util.ArrayList;
    22  import java.util.Calendar;
    23  import java.util.Date;
    24  import java.util.Iterator;
    25  import java.util.List;
    26  import org.apache.commons.logging.Log;
    27  import org.apache.commons.logging.LogFactory;
    28  import org.apache.roller.planet.business.PlanetFactory;
    29  import org.apache.roller.planet.business.PlanetManager;
    30  import org.apache.roller.planet.pojos.Planet;
    31  import org.apache.roller.planet.pojos.SubscriptionEntry;
    32  import org.apache.roller.planet.pojos.PlanetGroup;
    33  import org.apache.roller.planet.pojos.Subscription;
    34  import org.apache.roller.weblogger.business.URLStrategy;
    35  
    36  
    37  /**
    38   * Paging through a collection of planet entries.
    39   */
    40  public class PlanetEntriesPager extends AbstractPager {
    41      
             /* 
    P/P       *  Method: org.apache.roller.weblogger.ui.rendering.pagers.PlanetEntriesPager__static_init
              * 
              *  Postconditions:
              *    init'ed(log)
              */
    42      private static Log log = LogFactory.getLog(PlanetEntriesPager.class);
    43      
    44      private String feedURL = null;
    45      private String groupHandle = null;
    46      private String locale = null;
    47      private int sinceDays = -1;
    48      private int length = 0;
    49      
    50      // the collection for the pager
    51      private List entries = null;
    52      
    53      // are there more items?
    54      private boolean more = false;
    55      
    56      
    57      public PlanetEntriesPager(
    58              URLStrategy    strat,
    59              String         feedURL,
    60              String         groupHandle,
    61              String         baseUrl,
    62              String         locale,
    63              int            sinceDays,
    64              int            page,
    65              int            length) {
    66          
                 /* 
    P/P           *  Method: void org.apache.roller.weblogger.ui.rendering.pagers.PlanetEntriesPager(URLStrategy, String, String, String, String, int, int, int)
                  * 
                  *  Preconditions:
                  *    (soft) length <= 232-2
                  *    (soft) log != null
                  *    (soft) sinceDays <= 231
                  * 
                  *  Postconditions:
                  *    this.entries == &new ArrayList(getItems#2)
                  *    this.feedURL == feedURL
                  *    init'ed(this.feedURL)
                  *    this.groupHandle == groupHandle
                  *    init'ed(this.groupHandle)
                  *    this.length == length
                  *    (soft) this.length <= 232-2
                  *    this.locale == locale
                  *    init'ed(this.locale)
                  *    init'ed(this.more)
                  *    ...
                  */
    67          super(strat, baseUrl, page);
    68          
    69          this.feedURL = feedURL;
    70          this.groupHandle = groupHandle;
    71          this.locale = locale;
    72          this.sinceDays = sinceDays;
    73          this.length = length;
    74          
    75          // initialize the collection
    76          getItems();
    77      }
    78      
    79      
    80      public List getItems() {
    81          
                 /* 
    P/P           *  Method: List getItems()
                  * 
                  *  Preconditions:
                  *    init'ed(this.entries)
                  *    (soft) log != null
                  *    (soft) init'ed(this.feedURL)
                  *    (soft) init'ed(this.groupHandle)
                  *    (soft) this.length <= 232-2
                  *    (soft) this.length*this.page in -231..232-1
                  *    (soft) init'ed(this.page)
                  *    (soft) this.sinceDays <= 231
                  * 
                  *  Presumptions:
                  *    java.util.Calendar:getInstance(...)@88 != null
                  *    org.apache.roller.planet.business.Planet:getPlanetManager(...)@96 != null
                  *    org.apache.roller.planet.business.PlanetFactory:getPlanet(...)@96 != null
                  *    org.apache.roller.planet.business.PlanetManager:getEntries(...)@102 != null
                  *    org.apache.roller.planet.business.PlanetManager:getEntries(...)@105 != null
                  *    ...
                  * 
                  *  Postconditions:
                  *    return_value == One-of{old this.entries, &new ArrayList(getItems#2)}
                  *    return_value != null
                  *    this.entries == return_value
                  *    possibly_updated(this.more)
                  *    new ArrayList(getItems#2) num objects <= 1
                  * 
                  *  Test Vectors:
                  *    this.entries: Inverse{null}, Addr_Set{null}
                  *    this.feedURL: Addr_Set{null}, Inverse{null}
                  *    this.groupHandle: Addr_Set{null}, Inverse{null}
                  *    this.sinceDays: {-231..0}, {1..231}
                  */
    82          if (entries == null) {
    83              // calculate offset
    84              int offset = getPage() * length;
    85              
    86              Date startDate = null;
    87              if(sinceDays > 0) {
    88                  Calendar cal = Calendar.getInstance();
    89                  cal.setTime(new Date());
    90                  cal.add(Calendar.DATE, -1 * sinceDays);
    91                  startDate = cal.getTime();
    92              }
    93              
    94              List results = new ArrayList();
    95              try {
    96                  PlanetManager planetManager = PlanetFactory.getPlanet().getPlanetManager();
    97                  Planet planet = planetManager.getPlanet("default");
    98                  
    99                  List entries = null;
   100                  if (feedURL != null) {
   101                      Subscription sub = planetManager.getSubscription(feedURL);
   102                      entries = planetManager.getEntries(sub, offset, length+1);
   103                  } else if (groupHandle != null) {
   104                      PlanetGroup group = planetManager.getGroup(planet, groupHandle);
   105                      entries = planetManager.getEntries(group, startDate, null, offset, length+1);
   106                  } else {
   107                      PlanetGroup group = planetManager.getGroup(planet, "all");
   108                      entries = planetManager.getEntries(group, startDate, null, offset, length+1);
   109                  }
   110                  
   111                  // wrap 'em
   112                  int count = 0;
   113                  for (Iterator it = entries.iterator(); it.hasNext();) {
   114                      SubscriptionEntry entry = (SubscriptionEntry) it.next();
   115                      // TODO needs pojo wrapping from planet
+  116                      if (count++ < length) { 
   117                          results.add(entry);
   118                      } else {
   119                          more = true;
   120                      }
   121                  }
   122                  
   123              } catch (Exception e) {
   124                  log.error("ERROR: get aggregation", e);
   125              }
   126              
   127              entries = results;
   128          }
   129          
   130          return entries;
   131      }
   132      
   133      
   134      public boolean hasMoreItems() {
                 /* 
    P/P           *  Method: bool hasMoreItems()
                  * 
                  *  Preconditions:
                  *    init'ed(this.more)
                  * 
                  *  Postconditions:
                  *    return_value == this.more
                  *    init'ed(return_value)
                  */
   135          return more;
   136      }
   137  }
   138  
   139