RMISearchCenter


1   /*
2    * RMISearchCenter.java
3    *
4    * Created on 29. duben 2004, 16:08
5    */
6   
7   package SOFA.SOFAnet.Search.RMI;
8   
9   import SOFA.SOFAnet.Search.*;
10  import SOFA.SOFAnet.Core.SearchOps;
11  import SOFA.SOFAnet.Repository.Repository;
12  import SOFA.SOFAnet.Repository.NodeNameFilter;
13  import SOFA.SOFAnet.Repository.NodeInfo;
14  import java.util.*;
15  import java.rmi.RemoteException  ;
16  import java.rmi.Naming  ;
17  import java.net.MalformedURLException  ;
18  
19  /**
20   * Managing class of RMI implementation of search subsystem of the SOFAnet.
21   * <p>
22   * It handles:
23   * <ul>
24   * <li>loading of search configuration
25   * <li>search connections to other nodes
26   * <li>creation of RMI server and client
27   * <li>"collectors" - objects that collects replies for search requests.
28   * </ul>
29   *
30   * @author  Ladislav Sobr
31   */
32  public class RMISearchCenter
33  {
34    private Repository rep;
35    private SearchOps searchOps;
36    
37    private RMISearchClient client;
38    private RMISearchServer server;
39    
40    private List rmiSearchConnections;
41    private RMISearchConfig config;
42    private List seenSearchRequestIDs;
43    private Map rmiSearchCollectors;
44    boolean started;
45    private Random randomGenerator;
46    private String   myNodeName;
47    
48    /** Creates a new instance of RMISearchCenter */
49    public RMISearchCenter()
50    {
51      started = false;
52      
53      client = new RMISearchClient(this);
54      server = null;
55      
56      rmiSearchConnections = Collections.synchronizedList(new LinkedList());
57      seenSearchRequestIDs = Collections.synchronizedList(new LinkedList());
58      rmiSearchCollectors = Collections.synchronizedMap(new HashMap());
59      
60      randomGenerator = new Random();
61      
62      myNodeName = NodeInfo.getLocalNodeName();
63    }
64    
65    public void setRepository(Repository repository)
66    {
67      rep = repository;
68    }
69  
70    public void setSearchOps(SearchOps searchOps)
71    {
72      this.searchOps = searchOps;
73    }
74  
75    public SearchInterface getSearchInterface()
76    {
77      return client;
78    }
79    
80    /** Starts RMI search subsystem */
81    public void start() throws RMISearchException
82    {
83      //load configuration
84      config = new RMISearchConfig(rep, rmiSearchConnections);
85      config.loadFromStorage(true);
86      
87      started = true;
88      
89      //connect RMI search connections
90      synchronized (rmiSearchConnections)
91      {
92        Iterator it = rmiSearchConnections.iterator();
93        while (it.hasNext())
94        {
95          RMISearchConnection connection = (RMISearchConnection)it.next();
96          connection.connect();
97        }
98      }
99      
100     //run RMI search server
101    
102     NodeInfo myNodeInfo = new NodeInfo();
103     try
104     {
105       myNodeInfo.setNodeName(myNodeName);
106     }
107     catch (NodeInfo.InvalidNodeNameException e)
108     {
109       throw new RMISearchException("Invalid name of local SOFA node: " + myNodeName, e);
110     }
111     
112     try
113     {
114       server = new RMISearchServer(this, searchOps, myNodeInfo);
115       Naming.rebind("//" + myNodeInfo.getAddressAndPort() + "/SOFAnet/RMISearchServer", server);
116     }
117     catch (RemoteException   e)
118     {
119       throw new RMISearchException("RMI search server failed to start", e);
120     }
121     catch (MalformedURLException   e)
122     {
123       throw new RMISearchException("RMI search server failed to start", e);
124     }
125     
126   }
127   
128   /** Returns configuration of the RMI search subsystem */
129   public RMISearchConfiguration getConfiguration()
130   {
131     return config.getConfiguration();
132   }
133   
134   /** Sets configuration of the RMI search subsystem */
135   public void setConfiguration(RMISearchConfiguration configuration)
136   {
137     config.setConfiguration(configuration);
138   }
139   
140   /**
141    * Reloads configuration of the RMI search subsystem and makes it active.
142    * <p>
143    * Old connections are not destroyed, the new one are created.
144    */
145   public void applyConfiguration()
146   {
147     config.loadFromStorage(false);
148     
149     //connect new RMI search connections
150     synchronized (rmiSearchConnections)
151     {
152       Iterator it = rmiSearchConnections.iterator();
153       while (it.hasNext())
154       {
155         RMISearchConnection connection = (RMISearchConnection)it.next();
156         if (!connection.isConnected()) connection.connect();
157       }
158     }
159     
160   }
161   
162   /** Returns list with search connections (RMISearchConnection) to other nodes */
163   List getRMISearchConnections()
164   {
165     return rmiSearchConnections;
166   }
167   
168   boolean isStarted()
169   {
170     return started;
171   }
172   
173   /** Returns node filter that restricts which nodes can connect to this node */
174   NodeNameFilter getNodeFilter()
175   {
176     if (!started) return null;
177     return config.getNodeFilter();
178   }
179   
180   /** Returns list of seen search request IDs (SearchRequestID) - it is used to stop flood routing */
181   List getSeenSearchRequestIDs()
182   {
183     return seenSearchRequestIDs;
184   }
185   
186   /** Returns new collector for new search request */
187   RMISearchCollector newCollector()
188   {
189     int requestMark;
190     
191     synchronized (rmiSearchCollectors)
192     {
193       do
194       {
195         requestMark = randomGenerator.nextInt();
196       } while (rmiSearchCollectors.get(new Integer  (requestMark)) != null);
197       
198       RMISearchCollector collector = new RMISearchCollector(this, requestMark, myNodeName);
199       rmiSearchCollectors.put(new Integer  (requestMark), collector);
200       return collector;
201     }
202   }
203   
204   /** Returns existing collector that belongs to concrete search request */
205   RMISearchCollector getCollector(int requestMark)
206   {
207     return (RMISearchCollector)rmiSearchCollectors.get(new Integer  (requestMark));
208   }
209   
210   /** Deletes colector for concrete search request */
211   void removeCollector(int requestMark)
212   {
213     rmiSearchCollectors.remove(new Integer  (requestMark));
214   }
215 }
216
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