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Revision 533

Added by berkley about 24 years ago

can now download a document from a server

View differences:

src/edu/ucsb/nceas/metacat/ReplicationHandler.java
52 52 
   */
53 53 
  public void run()
54 54 
  {
55 
    System.out.println("replicationHandler is running");
56 55 
    //find out the last_checked time of each server in the server list and
57 56 
    //send a query to each server to see if there are any documents in
58 57 
    //xml_documents with an update_date > last_checked
......
60 59 
    {
61 60 
      conn = util.openDBConnection();
62 61 
      serverList = buildServerList(conn);
63 
      System.out.println("Server list: " + serverList.toString());
64 62 
      update(serverList, conn);
63 
      conn.close();
65 64 
    }
66 65 
    catch (Exception e)
67 66 
    {
......
93 92 
    String update;
94 93 
    Vector responses = new Vector();
95 94 
    ReplMessageHandler message = new ReplMessageHandler();
95 
    Hashtable updateDocs = new Hashtable();
96 
    URL u;
97 
    InputStreamReader istream;
96 98
97 99 
    try
98 100 
    {
......
109 111
110 112 
        update = update.replace(' ', '+');
111 113
112 
        URL u = new URL("http://" + server + "?update=" + update);
113 
        InputStreamReader istream = new InputStreamReader(u.openStream());
114 
        u = new URL("http://" + server + "?update=" + update);
115 
        istream = new InputStreamReader(u.openStream());
114 116 
        while((istreamInt = istream.read()) != -1)
115 117 
        {
116 118 
          istreamChar = (char)istreamInt;
......
118 120 
        }
119 121 
        responses.add(serverResponse.toString()); //list of updates
120 122 
      }
121 
      //System.out.println("responses: " + responses.toString());
122 123 

  		




  123
  124
  
    
      //initialize the parser


  		




  124
  125
  
    
      XMLReader parser = initParser(message);


  		




  ......




  129
  130
  
    
                     (String)(responses.elementAt(i)))));


  		




  130
  131
  
    
        Vector v = new Vector(message.getResultVect());


  		




  131
  132
  
    
        for(int j=0; j<v.size(); j++)


  		




  132
  
  
    
        {


  		




  
  133
  
    
        { //go through each update vector and update or insert


  		




  
  134
  
    
          //a new document


  		




  133
  135
  
    
          Vector w = new Vector((Vector)(v.elementAt(j)));


  		




  134
  
  
    
          System.out.print("param " + j + ": " + w.toString());


  		




  135
  
  
    
          //so now we have a list of the documents that need to be updated, so 


  		




  136
  
  
    
          //now we need to request them. from the server and update them here  


  		




  
  136
  
    
          String docid = (String)w.elementAt(0);


  		




  
  137
  
    
          String docServer = (String)w.elementAt(2);


  		




  
  138
  
    

  		




  
  139
  
    
          //send a message to the server requesting each document


  		




  
  140
  
    
          URL getDocURL = new URL("http://" + docServer + "?getdocument="+


  		




  
  141
  
    
                      docid);


  		




  
  142
  
    
          InputStreamReader getDocIstream = new InputStreamReader(


  		




  
  143
  
    
                                                getDocURL.openStream());


  		




  
  144
  
    

  		




  
  145
  
    
          //update the document into the DB


  		




  
  146
  
    
          String action = getAction(docid);


  		




  
  147
  
    
          String newDocid = DocumentImpl.write(conn, getDocIstream, action, 


  		




  
  148
  
    
                                               docid, null, null);


  		




  
  149
  
    
          //System.out.println("newDocid: " + newDocid);


  		




  137
  150
  
    
        }


  		




  138
  
  
    
        System.out.println("");


  		




  139
  151
  
    
      }


  		




  
  152
  
    
      //update the last_update field for each server to the current date/time


  		




  140
  153
  
    
      


  		




  141
  154
  
    
      


  		




  142
  155
  
    
    }


  		




  ......




  144
  157
  
    
    {


  		




  145
  158
  
    
      System.out.println("Error in replicationHandler.update(): " + 


  		




  146
  159
  
    
                         e.getMessage());


  		




  
  160
  
    
      e.printStackTrace(System.out);


  		




  147
  161
  
    
    }


  		




  148
  162
  
    
  }


  		




  149
  163
  
    
  


  		




  150
  164
  
    
  /**


  		




  
  165
  
    
   * Checks to see if a document is already in the DB.  Returns


  		




  
  166
  
    
   * "UPDATE" if it is, "INSERT" if it isn't


  		




  
  167
  
    
   */


  		




  
  168
  
    
  private static String getAction(String docid)


  		




  
  169
  
    
  {


  		




  
  170
  
    
    try


  		




  
  171
  
    
    {


  		




  
  172
  
    
      MetaCatUtil util = new MetaCatUtil();


  		




  
  173
  
    
      StringBuffer sql = new StringBuffer();


  		




  
  174
  
    
      sql.append("select docid from xml_documents where docid like '");


  		




  
  175
  
    
      sql.append(docid).append("'");


  		




  
  176
  
    
      Connection conn = util.openDBConnection();


  		




  
  177
  
    
      PreparedStatement pstmt = conn.prepareStatement(sql.toString());


  		




  
  178
  
    
      pstmt.execute();


  		




  
  179
  
    
      ResultSet rs = pstmt.getResultSet();


  		




  
  180
  
    

  		




  
  181
  
    
      if(rs.next())


  		




  
  182
  
    
      {


  		




  
  183
  
    
        conn.close();


  		




  
  184
  
    
        return "UPDATE";


  		




  
  185
  
    
      }


  		




  
  186
  
    
      else


  		




  
  187
  
    
      {


  		




  
  188
  
    
        conn.close();


  		




  
  189
  
    
        return "INSERT";


  		




  
  190
  
    
      }


  		




  
  191
  
    
    }


  		




  
  192
  
    
    catch(Exception e)


  		




  
  193
  
    
    {


  		




  
  194
  
    
      System.out.println("error in replicationHandler.getAction: " + 


  		




  
  195
  
    
                          e.getMessage());


  		




  
  196
  
    
    }


  		




  
  197
  
    
    return "";


  		




  
  198
  
    
  }


  		




  
  199
  
    
  


  		




  
  200
  
    
  /**


  		




  151
  201
  
    
   * Method to initialize the message parser


  		




  152
  202
  
    
   */


  		




  153
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  private static XMLReader initParser(ReplMessageHandler rmh)


  		












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