versioningrdbmssail.java

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            if (!hn)
            {
              rs.close();
              st.close();
              con.close();
            }
          } catch (SQLException ex) {
            throw new SailInternalException(ex);
          }
        }
        return res;
      }
      public void remove(){}
    };
  } // getVersionIds()


  /**
   * Create a labeled version for a statte of the repository assigning the
   * necessary mata-information about thet operation.
   * @param stateUID of a particular repository state
   * @param label associated with the state
   *
   * NOTE: This method can throw a security exception if the request is made on
   * behalf of the user with insufficent rights to create versions
   */
  public void labelState(long stateUID, String label)
  {
    int usid = getCurrentUserID();
    try {
      Connection con = RDBMS().getConnection();
      java.sql.Statement st = con.createStatement();
      ResultSet rs = st.executeQuery("select max(vid) from "+VERSION_TABLE);
      int maxvid = 0;
      if (rs.next())
        maxvid = rs.getInt(1);
      rs.close();
      // ad a system default label
      if (label == null || label.length() ==0)
        label = "New label "+(maxvid+1);
      st.executeUpdate("insert into "+VERSION_TABLE+
                       " VALUES ("+(maxvid+1)+" , "+usid+", "+stateUID+" ,"+
                       " '"+label+"')" );
      st.close();
      con.close();
    } catch (SQLException e) {
      throw new SailInternalException(e);
    }
  } //labelState

  /**
   * Create a labeled version of the curent repository state.
   * @param label to be associated with the state
   * NOTE: This method can throw a security exception if the request is made on
   * behalf of the user with insufficent rights to create versions
   */
  public void labelCurrentState(String label)
  {
    int saveState = VersionUid;
    VersionUid = -1;
    int stateUID = getStateUid();
    VersionUid = saveState;
    labelState(stateUID, label);
  }

  /**
   * Restore the repository to previous state removing all statements added
   * after the value of the update counter and revive all removed ones.
   * @param stateUID - the update counter of a particular repository state
   * NOTE: This method can throw a security exception if the request is made on
   * behalf of the user with insufficent rights to revert the repository
   */
  public void revertToState(long stateUID)
  {
    throw new RuntimeException( "revertToState is not implemented" );
  }

  /**
   * Which Sail class should be used to access the intermediate branched versions
   * of the repository - to speed up the work with the RO version we use the most
   * basic sail implementation
   * @return the name of sail class.
   */
  protected String alias()
  {
    return super.getClass().getSuperclass().getName();
  }
  /**
   * Sets the repository to given statete for further read operations.
   * @param stateUID - the update counter of a particular repository state
   */
  public void workWithState(long stateUID)
  {

    //  FIXME: should check if it is possible
    SessionContext sc = SessionContext.getContext();
    int vs = sc.VersionState;
    if (vs > 0)
    {
      try {
        Connection con = RDBMS().getConnection();
        java.sql.Statement st = con.createStatement();
        ResultSet rs = st.executeQuery("SELECT refs FROM "+ACTIVE_STATES_TABLE+
                                       " WHERE uid ="+vs);
        boolean toRemove = false;
        if (rs.next())
        {
          int refs = rs.getInt(1);
          if (refs == 1)
            toRemove = true;
        }
        rs.close();
        st.close();
        con.close();
        if (!toRemove)
          RDBMS().executeUpdate("UPDATE "+ACTIVE_STATES_TABLE+
                                " SET refs=refs-1 WHERE uid="+vs);
        else {
          RDBMS().executeUpdate("DELETE FROM "+ACTIVE_STATES_TABLE+
                                " WHERE uid="+vs);
        } // remove or not

      } catch (SQLException e) {
        throw new SailInternalException(e);
      }
    } // if (vs > 0)
    if (stateUID > 0)
    {
      try {
        Connection con = RDBMS().getConnection();
        java.sql.Statement st = con.createStatement();
        ResultSet rs = st.executeQuery("SELECT refs FROM "+ACTIVE_STATES_TABLE+
                                       " WHERE uid ="+stateUID);
        boolean toInsert = true;
        if (rs.next())
        {
          int refs = rs.getInt(1);
          toInsert = false;
        }
        rs.close();
        if (!toInsert)
          RDBMS().executeUpdate("UPDATE "+ACTIVE_STATES_TABLE+
                                " SET refs=refs+1 WHERE uid="+stateUID);
        else {
          RDBMS().executeUpdate("INSERT INTO "+ACTIVE_STATES_TABLE+
                                " VALUES ( "+stateUID+" , "+1+")");

          branchState(stateUID);
        } // insert or not
        st.close();
        con.close();
      } catch (SQLException e) {
        throw new SailInternalException(e);
      }
    } // if (stateUID > 0)
  }

  public String branchState(long stateUID)
  {
    String result = "";
    SessionContext sc = SessionContext.getContext();

    try {
      SystemConfig sysConfig = SesameServer.getSystemConfig();

      String branchId = sc.repository + "branch_" + getSuffix((int)stateUID);

      RepositoryConfig rc = sysConfig.cloneRepository(sc.repository, branchId);
      rc.setTitle("branch of " + getSuffix((int)stateUID) + " " + rc.getTitle());
      sc.repository = branchId;

      boolean b_do_not_append_data = false;
      boolean b_do_not_create_data = true;

      Iterator iter = rc.getSailList().iterator();
      while (iter.hasNext())
      {
        SailConfig sailConfig = (SailConfig)iter.next();

        String param = sailConfig.getSailClass();
        if (param.equals(getClass().getName())) {
          sailConfig.setSailClass(alias());
        }

        String url = sailConfig.getParameter("jdbcUrl");
        if (url != null)
        {
          int pos = url.lastIndexOf('/');
          String repdb = url.substring(pos+1);
          repdb += getSuffix((int)stateUID)+"branch";

          url = url.substring(0,pos+1);
          sailConfig.setParameter("jdbcUrl",url+repdb);
          String user = sailConfig.getParameter("user");
          String pass = sailConfig.getParameter("password");

          Connection c1 = null;
          try {
            c1 = java.sql.DriverManager.getConnection(url+repdb, user, pass);
          }
          catch (SQLException ignore) {}

          if (c1 != null)
          {
            c1.close();
            b_do_not_append_data = true && b_do_not_create_data;
            break;
          }

          if (b_do_not_create_data)
          {
            if (adminConnection == null) {
              adminConnection = java.sql.DriverManager.getConnection(url, user, pass);
            }

            java.sql.Statement st2 = adminConnection.createStatement();
            try {
              st2.execute("DROP DATABASE "+repdb);
            } catch(SQLException e) { }

            st2.execute("CREATE DATABASE "+repdb);
            createdRepositories.add(repdb);
            st2.close();
            b_do_not_create_data = false;
          }
        } // not have url
      } //while

      // Give admin user access to new repository
      UserInfo uiAdmin = sysConfig.getUserInfo(1);
      uiAdmin.addReadWriteAccess(rc);

      if (b_do_not_append_data == false)
      {
        ThreadLog.trace("branch begin");
        
        LocalService service = SesameServer.getLocalService();
        
        service.login(uiAdmin.getLogin(), uiAdmin.getPassword());
        
        LocalRepository rep = (LocalRepository)service.getRepository(rc.getRepositoryId());
        
        Sail otherSail = rep.getSail();
        
        ThreadLog.trace("branch end");
        Connection con = RDBMS().getConnection();
        java.sql.Statement st = con.createStatement();
        ResultSet rs = null;
        if (otherSail != null)
        {
          int old_id = sc.userID;
          sc.userID = 1; // as admin
          rs = st.executeQuery(
              "SELECT n1.name, r1.localname,n2.name, r2.localname, n3.name, r3.localname FROM "+
                TRIPLES_HIST_TABLE+" th ,"+
                RESOURCES_TABLE+" r1, "+ // was HIST_
                NAMESPACES_TABLE+" n1, "+
                RESOURCES_TABLE+" r2, "+ // was HIST_
                NAMESPACES_TABLE+" n2, "+
                RESOURCES_TABLE+" r3, "+ // was HIST_
                NAMESPACES_TABLE+" n3 "+
              " WHERE th.explicit="+RDBMS().TRUE+" AND th.BornAt <= "+stateUID+
              " AND (th.DiedAt > "+stateUID+" OR th.DiedAt = 0)"+
              " AND r1.id=th.subject"+
              " AND r2.id=th.predicate"+
              " AND r3.id=th.object"+
              " AND r1.namespace =n1.id"+
              " AND r2.namespace =n2.id"+
              " AND r3.namespace =n3.id"
              );
          ((RdfRepository)otherSail).startTransaction();
          while (rs.next())
          {
            /**@todo: instead of resource use the new Impl objects import triples with Resource objects */
            String nsString = rs.getString(1);
            Resource subj = null;
            if (nsString == null || 0==nsString.compareToIgnoreCase("NULL"))
              subj = new org.openrdf.model.impl.BNodeImpl(rs.getString(2));
            else
              subj = new org.openrdf.model.impl.URIImpl(nsString, rs.getString(2));

            URI pred = new org.openrdf.model.impl.URIImpl(rs.getString(3), rs.getString(4));

            Value obj = null;
            String valString = rs.getString(5);
            if (valString == null || 0==valString.compareToIgnoreCase("NULL"))
              obj = new org.openrdf.model.impl.BNodeImpl(rs.getString(6));
            else
              obj = new org.openrdf.model.impl.URIImpl(valString, rs.getString(6));
            try {
              ((RdfRepository)otherSail).addStatement(subj,pred, obj);
            } catch (SailUpdateException e) {
              throw new SailInternalException(e);
            }
          }
          rs.close();

          rs = st.executeQuery(
              "SELECT n1.name, r1.localname,n2.name, r2.localname, l1.label, l1.language FROM "+
              TRIPLES_HIST_TABLE+" th ,"+
              RESOURCES_TABLE+" r1, "+ // was HIST_
              NAMESPACES_TABLE+" n1, "+
              RESOURCES_TABLE+" r2, "+ // was HIST_
              NAMESPACES_TABLE+" n2, "+
              LITERALS_TABLE+" l1 "+ // was HIST_
              " WHERE th.explicit="+RDBMS().TRUE+" AND th.BornAt <= "+stateUID+
              " AND (th.DiedAt > "+stateUID+" OR th.DiedAt = 0)"+
              " AND r1.id = th.subject"+
              " AND r2.id = th.predicate"+
              " AND l1.id = th.object"+
              " AND r1.namespace =n1.id"+
              " AND r2.namespace =n2.id"
              );
          while (rs.next())
          {
            /**@todo: instead of resource use the new Impl objects import triples with Literal objects*/
            String nsString = rs.getString(1);
            Resource subj = null;
            if (nsString == null || 0==nsString.compareToIgnoreCase("NULL"))
              subj = new org.openrdf.model.impl.BNodeImpl(rs.getString(2));
            else
              subj = new org.openrdf.model.impl.URIImpl(nsString, rs.getString(2));
            URI pred = new org.openrdf.model.impl.URIImpl(rs.getString(3), rs.getString(4));
            String val = rs.getString(5);
            String lang = rs.getString(6);
            Value obj = new org.openrdf.model.impl.LiteralImpl(val, lang);
            try {
              ((RdfRepository)otherSail).addStatement(subj,pred, obj);
            } catch (SailUpdateException e) {
              throw new SailInternalException(e);
            }
          }
          rs.close();
          ((RdfRepository)otherSail).commitTransaction();

          // we should update the namespaces
          NamespaceIterator nsIter = getNamespaces();
          while (nsIter.hasNext()) {
            nsIter.next();
            try {
              ((RdfRepository)otherSail).changeNamespacePrefix(nsIter.getName(), nsIter.getPrefix());
            }
            catch (SailUpdateException e) {
              ThreadLog.warning(
                  "Unable to set namespace prefix '" + nsIter.getPrefix() +
                  "' for namespace '" + nsIter.getName() + "': " +
                  e.getMessage());
            }
          }

          sc.userID = old_id; // as current user
        } // have a Sail
        st.close();
        con.close();
      }