/src/edu/ucsb/nceas/metacat/AccessControlList.java - Diff - Metacat - Ecoinformatics Redmine

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Revision 688

Added by bojilova about 23 years ago

added new "getaccesscontrol" action for a given docid

       /**
        * Construct an instance of the AccessControlList class.
        * It is used by the permission check up from DBQuery and DocumentImpl
        * and for "getaccesscontrol" action
        * It is used by the permission check up from DBQuery or DocumentImpl
        * and from "getaccesscontrol" action
+       *
        * @param conn the JDBC connection where acl info is get
        */
-...
         this.principal = new Vector();
         this.permission = 0;
         this.ticketCount = 0;
         this.publicAcc = null;
         this.serverCode = serverCode;
         // Initialize the parser and read the queryspec
-...
       /**
        * Construct an instance of the AccessControlList class.
        * It parse acl file and loads acl data into db connection.
        * It parses eml-access file and loads acl data into db connection.
        * It is used from command line execution.
+       *
        * @param conn the JDBC connection where acl data are loaded
        * @param docid the Accession# of the document with the acl data
        * @param aclfilename the name of acl file containing acl data
        * @param user the user connected to MetaCat servlet and owns the document
        * @param group the group to which user belongs
        */
       public AccessControlList( Connection conn, String aclid, String aclfilename,
                                String user, String group )
-...
+      }
       /**
        * callback method used by the SAX Parser when beginning of the document
        * Callback method used by the SAX Parser when beginning of the document
        */
       public void startDocument() throws SAXException
+      {
-...
+      }
       /**
        * callback method used by the SAX Parser when the start tag of an
        * Callback method used by the SAX Parser when the start tag of an
        * element is detected. Used in this context to parse and store
        * the acl information in class variables.
        */
-...
+      }
       /**
        * callback method used by the SAX Parser when the text sequences of an
        * Callback method used by the SAX Parser when the text sequences of an
        * xml stream are detected. Used in this context to parse and store
        * the acl information in class variables.
        */
-...
+      }
       /**
        * callback method used by the SAX Parser when the end tag of an
        * Callback method used by the SAX Parser when the end tag of an
        * element is detected. Used in this context to parse and store
        * the acl information in class variables.
        */
       public void endElement (String uri, String localName, String qName)
              throws SAXException
+      {
         BasicNode leaving = (BasicNode)elementStack.pop();
         if ( leaving.getTagName().equals("resourceIdentifier") ) {
         BasicNode leaving = (BasicNode)elementStack.pop();
         String leavingTagName = leaving.getTagName();
         if ( leavingTagName.equals("resourceIdentifier") ) {
           try {
             // make a relationship for @aclid on the current resource(docurl)
-...
             throw new SAXException(sqle);
+          }
         } else if ( leaving.getTagName().equals("allow") ) {
         } else if ( leavingTagName.equals("allow") ||
                     leavingTagName.equals("deny")    ) {
           if ( permission > 0 ) {
             // insert into db calculated permission for the list of principals
             try {
               insertPermissions("allowed");
               insertPermissions(leavingTagName);
             } catch (SQLException sqle) {
               throw new SAXException(sqle);
+            }
+          }
           // reset the allowed permission
           // reset the allow/deny permission
           principal = new Vector();
           permission = 0;
           beginTime = null;
           endTime = null;
           ticketCount = 0;
         } else if ( leaving.getTagName().equals("deny") ) {
           if ( permission > 0 ) {
         } else if ( leavingTagName.equals("resource") ) {
             // insert into db calculated permission for the list of principals
           // update public access for the list of resources
           if ( publicAcc != null ) {
             try {
               insertPermissions("denied");
               updatePublicAccess(publicAcc);
             } catch (SQLException sqle) {
               throw new SAXException(sqle);
+            }
+          }
           // reset the denied permission
           principal = new Vector();
           permission = 0;
           beginTime = null;
           endTime = null;
           ticketCount = 0;
         } else if ( leaving.getTagName().equals("resource") ) {
           // update public access for the list of resources
           try {
             updatePublicAccess(publicAcc);
           } catch (SQLException sqle) {
             throw new SAXException(sqle);
+          }
           // reset the resource
           resourceID = new Vector();
-...
+      }
       /** SAX Handler that receives notification of DOCTYPE. Sets the DTD */
       /**
         * SAX Handler that receives notification of DOCTYPE. Sets the DTD.
         * @param name name of the DTD
         * @param publicId Public Identifier of the DTD
         * @param systemId System Identifier of the DTD
         */
       public void startDTD(String name, String publicId, String systemId)
                   throws SAXException {
         docname = name;
-...
+      }
       /**
        * SAX Handler that receives notification of the start of entities
        * SAX Handler that receives notification of the start of entities.
        * @param name name of the entity
        */
       public void startEntity(String name) throws SAXException {
         if (name.equals("[dtd]")) {
-...
+      }
       /**
        * SAX Handler that receives notification of the end of entities
        * SAX Handler that receives notification of the end of entities.
        * @param name name of the entity
        */
       public void endEntity(String name) throws SAXException {
         if (name.equals("[dtd]")) {
-...
+      }
       /**
        * get the document name
        * Get the document name.
        */
       public String getDocname() {
         return docname;
+      }
       /**
        * get the document processing state
        * Get the document processing state.
        */
       public boolean processingDTD() {
         return processingDTD;
+      }
       /** Delete from db all permission for resources related to @aclid if any */
       /* Delete from db all permission for resources related to @aclid if any.*/
       private void deletePermissionsForRelatedResources(String aclid)
               throws SQLException
+      {
-...
         stmt.close();
+      }
       /**
        * Deletes all of the relations with a docid of @docid.
        * @param docid the docid to delete.
        */
       public void deleteRelations(String docid)
       /* Delete all of the relations with a docid of @docid from db connection.*/
       private void deleteRelations(String docid)
               throws SQLException
+      {
         Statement stmt = conn.createStatement();
-...
         stmt.close();
+      }
       /** Insert relationship into db for @aclid on @resourceURL  */
       /* Insert relationship for @aclid on @resourceURL into db connection.*/
       private void insertRelation(String aclid, String resourceURL)
               throws SQLException
+      {
-...
         pstmt.close();
+      }
       /** Insert into db calculated permission for the list of principals */
       /* Insert into db calculated permission for the list of principals */
       private void insertPermissions( String permType )
               throws SQLException
+      {
-...
           } else {
             pstmt.setString(8, "");
+          }
           String docid;
           String prName;
           for ( int i = 0; i < resourceID.size(); i++ ) {
             pstmt.setString(1, (String)resourceID.elementAt(i));
             docid = (String)resourceID.elementAt(i);
             pstmt.setString(1, docid);
             for ( int j = 0; j < principal.size(); j++ ) {
               pstmt.setString(2, (String)principal.elementAt(j));
               prName = (String)principal.elementAt(j);
               pstmt.setString(2, prName);
               pstmt.execute();
               // check if there are conflict with permission's order
               String permOrderOpos = permOrder;
               int perm = getPermissions(permission, prName, docid, permOrder);
               if (  perm != 0 ) {
                 if ( permOrder.equals("allowFirst") ) {
                   permOrderOpos = "denyFirst";
                 } else if ( permOrder.equals("denyFirst") ) {
                   permOrderOpos = "allowFirst";
+                }
                 throw new SQLException("Permission(s) " + txtValue(perm) +
                           " for \"" + prName + "\" on document #" + docid +
                           " has/have been used with \"" + permOrderOpos + "\"");
+              }
+            }
+          }
           pstmt.close();
-...
+        }
+      }
       /** Update into db public read access for the list of resources */
       /* Update into db public "read" access for the list of resources. */
       private void updatePublicAccess(String publicAcc)
               throws SQLException
+      {
-...
+        }
+      }
       /** Check for @permission for @principal on @resourceID from db connection */
       /* Get permissions with permission order different than @permOrder. */
       private int getPermissions(int permission, String principal,
                                  String docid, String permOrder)
               throws SQLException
+      {
         PreparedStatement pstmt;
         pstmt = conn.prepareStatement(
                 "SELECT permission FROM xml_access " +
                 "WHERE docid LIKE ? " +
                 "AND principal_name LIKE ? " +
                 "AND perm_order NOT LIKE ?");
         pstmt.setString(1, docid);
         pstmt.setString(2, principal);
         pstmt.setString(3, permOrder);
         pstmt.execute();
         ResultSet rs = pstmt.getResultSet();
         boolean hasRow = rs.next();
         int perm = 0;
         while ( hasRow ) {
           perm = rs.getInt(1);
           perm = permission & perm;
           if ( perm != 0 ) {
             pstmt.close();
             return perm;
+          }
           hasRow = rs.next();
+        }
         pstmt.close();
         return 0;
+      }
       /* Get the int value of READ, WRITE or ALL. */
       private int intValue ( String permission )
+      {
         if ( permission.equals("READ") ) {
           return READ;
         } else if ( permission.equals("WRITE") ) {
           return WRITE;
         } else if ( permission.equals("ALL") ) {
           return ALL;
+        }
         return -1;
+      }
       /* Get the text value of READ, WRITE or ALL. */
       private String txtValue ( int permission )
+      {
         StringBuffer txtPerm = new StringBuffer("\"");
         if ( (permission & READ) != 0 ) {
           txtPerm.append("read");
+        }
         if ( (permission & WRITE) != 0 ) {
           if ( txtPerm.length() > 0 ) txtPerm.append(",");
           txtPerm.append("write");
+        }
         if ( (permission & ALL) != 0 ) {
           if ( txtPerm.length() > 0 ) txtPerm.append(",");
           txtPerm.append("all");
+        }
         return txtPerm.append("\"").toString();
+      }
       /* Read docid from @url. */
       private String getDocid ( String url ) throws SAXException
+      {
         MetaCatUtil util = new MetaCatUtil();
         try {
           URL urlobj = new URL(url);
           Hashtable urlParams = util.parseQuery(urlobj.getQuery());
           if ( urlParams.containsKey("docid") ) {
             return (String)urlParams.get("docid"); // return the docid value
           } else {
             throw new
             SAXException("\"docid\" not specified within " + url);
+          }
         } catch (MalformedURLException e) {
           throw new SAXException(e.getMessage());
+        }
+      }
       /**
         * Check from db connection if @principal has @permission on @resourceID.
         * @param permission permission type to check for
         * @param principal name of principal to check for @permission
         * @param resourceID resource identifier to check on
         */
       public boolean hasPermission ( String permission,
                                      String principal, String resourceID )
                      throws SQLException
-...
           } catch (SQLException e) {
             throw new
             SQLException("AccessControlList.hasPermission(): " +
                          "Error checking document's public access. " +
                           e.getMessage());
             SQLException("AccessControlList.hasPermission(). " +
                          "Error checking public access for document #"+resourceID+
                          ". " + e.getMessage());
+          }
+        }
-...
           } catch (SQLException e) {
             throw new
             SQLException("AccessControlList.hasPermission(): " +
                          "Error checking document's ownership. " + e.getMessage());
             SQLException("AccessControlList.hasPermission(). " +
                          "Error checking ownership for " + principal +
                          " on document #" + resourceID + ". " + e.getMessage());
+          }
           // check @principal's @permission on @resourceID from xml_access table
-...
                     "FROM xml_access " +
                     "WHERE docid LIKE ? " +
                     "AND principal_name LIKE ? " +
                     "AND perm_type LIKE ? " +
                     "AND sysdate BETWEEN nvl(begin_time,sysdate) " +
                                     "AND nvl(end_time,sysdate) " +
                     "AND perm_type LIKE ?");
             // check if it is "denied" first
                                     "AND nvl(end_time,sysdate)");
             // check if it is "deny" with "allowFirst" first
             // Bind the values to the query
             pstmt.setString(1, resourceID);
             pstmt.setString(2, principal);
             pstmt.setString(3, "denied");
             pstmt.setString(3, "deny");
             pstmt.execute();
             ResultSet rs = pstmt.getResultSet();
-...
                    ( permOrder.equals("allowFirst") ) &&
                    ( rs.wasNull() || ticketCount > 0 ) ) {
                 if ( !rs.wasNull() && ticketCount > 0 ) {
                   decreaseNumberOfAccess(accessValue,principal,resourceID,"denied");
                   decreaseNumberOfAccess(accessValue,principal,resourceID,"deny","allowFirst");
+                }
                 pstmt.close();
                 return false;
+              }
               hasRows = rs.next();
+            }
     //System.out.println("Passed the check for denied access");
     //System.out.println("Passed the check for \"deny\" access with \"allowFirst\"");
             // it is not denied then check if it is "allowed"
             // it is not denied then check if it is "allow"
             // Bind the values to the query
             pstmt.setString(1, resourceID);
             pstmt.setString(2, principal);
             pstmt.setString(3, "allowed");
             pstmt.setString(3, "allow");
             pstmt.execute();
             rs = pstmt.getResultSet();
             hasRows = rs.next();
             while ( hasRows ) {
               accessValue = rs.getInt(1);
               permOrder = rs.getString(2);
               ticketCount = rs.getInt(3);
               if ( ( accessValue & intValue(permission) )==intValue(permission) &&
                    ( rs.wasNull() || ticketCount > 0 ) ) {
                 if ( !rs.wasNull() && ticketCount > 0 ) {
                   decreaseNumberOfAccess(accessValue,principal,resourceID,"allowed");
                   decreaseNumberOfAccess(accessValue,principal,resourceID,"allow",permOrder);
+                }
                 pstmt.close();
                 return true;
+              }
               hasRows = rs.next();
+            }
     //System.out.println("Passed the check for allowed access");
     //System.out.println("Passed the check for \"allow\" access");
             // ???
             // here there could be a check for the group's permission like
             // selfrecursive call to hasPermission(conn,permission,group,recourceId)
             //
             // it is not allowed then check if it is "deny" with "denyFirst"
             // Bind the values to the query
             pstmt.setString(1, resourceID);
             pstmt.setString(2, principal);
             pstmt.setString(3, "deny");
             pstmt.execute();
             rs = pstmt.getResultSet();
             hasRows = rs.next();
             while ( hasRows ) {
               accessValue = rs.getInt(1);
               permOrder = rs.getString(2);
               ticketCount = rs.getInt(3);
               if ( ( accessValue & intValue(permission) ) == intValue(permission) &&
                    ( permOrder.equals("denyFirst") ) &&
                    ( rs.wasNull() || ticketCount > 0 ) ) {
                 if ( !rs.wasNull() && ticketCount > 0 ) {
                   decreaseNumberOfAccess(accessValue,principal,resourceID,"deny","denyFirst");
+                }
                 pstmt.close();
                 return false;
+              }
               hasRows = rs.next();
+            }
     //System.out.println("Passed the check for \"deny\" access wirh \"denyFirst\"");
             pstmt.close();
             return false;
           } catch (SQLException e) {
             throw new
             SQLException("AccessControlList.hasPermission(): " +
                          "Error checking document's permission. " + e.getMessage());
             SQLException("AccessControlList.hasPermission(). " +
                          "Error checking " + permission + " permission for " +
                          principal + " on document #" + resourceID + ". " +
                          e.getMessage());
+          }
+        }
         return false;
+      }
       /** decrease the number of access to @resourceID for @principal */
       /* Decrease the number of access to @resourceID for @principal in db. */
       private void decreaseNumberOfAccess(int permission, String principal,
                                           String resourceID, String permType)
                                           String resourceID, String permType,
                                           String permOrder)
                    throws SQLException
+      {
         PreparedStatement pstmt;
-...
                 "WHERE docid LIKE ? " +
                 "AND principal_name LIKE ? " +
                 "AND permission LIKE ? " +
                 "AND perm_type LIKE ? " +
                 "AND perm_order LIKE ? " +
                 "AND sysdate BETWEEN nvl(begin_time,sysdate) " +
                                 "AND nvl(end_time,sysdate) " +
                 "AND perm_type LIKE ?");
                                 "AND nvl(end_time,sysdate)");
         // Bind the values to the query
         pstmt.setString(1, resourceID);
         pstmt.setString(2, principal);
         pstmt.setInt(3, permission);
         pstmt.setString(4, permType);
         pstmt.setString(5, permOrder);
         pstmt.execute();
         pstmt.close();
+      }
       // get the int value of READ, WRITE or ALL
       private int intValue ( String permission )
       /**
         * Get Access Control List information for document from db connetion.
         * User or Group should have permissions for reading
         * access control information for a document specified by @docid.
         * @param docid document identifier which acl info to get
         * @param user name of user connected to Metacat system
         * @param group name of user's group to which user belongs
         */
       public String getACL(String docid, String user, String group)
               throws SQLException
+      {
         if ( permission.equals("READ") ) {
           return READ;
         } else if ( permission.equals("WRITE") ) {
           return WRITE;
         } else if ( permission.equals("ALL") ) {
           return ALL;
+        }
         StringBuffer output = new StringBuffer();
         StringBuffer outTemp = new StringBuffer();
         MetaCatUtil util = new MetaCatUtil();
         String accDoctype = util.getOption("accessdoctype");
         String server = util.getOption("server");
         String docurl = "metacat://" + server + "/?docid=" + docid;
         String systemID;
         boolean isOwned = false;
         boolean hasPermission = false;
         String publicAcc;
         return -1;
+      }
       // get docid from @url
       private String getDocid ( String url ) throws SAXException
+      {
         MetaCatUtil util = new MetaCatUtil();
         String acfid = "";
         String acfid_prev = "";
         String principal;
         Vector principalArr = new Vector();
         int permission;
         int perm_prev = -1;
         String permType;
         String permOrder = "";
         String permOrder_prev = "";
         String beginTime = "";
         String begin_prev = "";
         String endTime = "";
         String end_prev = "";
         int ticketCount = -1;
         int ticket_prev = -1;
         try {
           URL urlobj = new URL(url);
           Hashtable urlParams = util.parseQuery(urlobj.getQuery());
           if ( urlParams.containsKey("docid") ) {
             return (String)urlParams.get("docid"); // return the docid value
           } else {
             throw new
             SAXException("\"docid\" not specified within " + url);
           isOwned = isOwned(docid, user);
           systemID = getSystemID(accDoctype);
           publicAcc = getPublicAccess(docid);
           output.append("<?xml version=\"1.0\"?>\n");
           output.append("<!DOCTYPE acl PUBLIC \"" + accDoctype + "\" \"" +
                         systemID + "\">\n");
           output.append("<acl authSystem=\"\">\n");
           PreparedStatement pstmt;
           pstmt = conn.prepareStatement(
                   "SELECT distinct accessfileid, principal_name, permission, " +
                   "perm_type, perm_order, to_char(begin_time,'mm/dd/yyyy'), " +
                   "to_char(end_time,'mm/dd/yyyy'), ticket_count " +
                   "FROM xml_access WHERE docid LIKE ? " +
                   "ORDER BY accessfileid, perm_order, perm_type, permission");
           // Bind the values to the query
           pstmt.setString(1, docid);
           pstmt.execute();
           ResultSet rs = pstmt.getResultSet();
           boolean hasRows = rs.next();
           while (hasRows) {
             acfid = rs.getString(1);
             principal = rs.getString(2);
             permission = rs.getInt(3);
             permType = rs.getString(4);
             permOrder = rs.getString(5);
             beginTime = rs.getString(6);
             endTime = rs.getString(7);
             ticketCount = rs.getInt(8);
             // if @docid is not owned by @user, only ACL info from that
             // access files to which @user/@group has "read" permission
             // is extracted
             if ( !isOwned ) {
               if ( !acfid.equals(acfid_prev) ) {
                 acfid_prev = acfid;
                 hasPermission = hasPermission("READ",user,acfid);
                 if ( !hasPermission && group != null ) {
                   hasPermission = hasPermission("READ",group,acfid);
+                }
+              }
               if ( !hasPermission ) {
                 rs.next();
                 continue;
+              }
+            }
             // open <resource> tag
             if ( !permOrder.equals(permOrder_prev) ) {
               // close </resource> tag if any was opened
               output.append(outTemp.toString());
               outTemp = new StringBuffer();
               if ( !permOrder_prev.equals("") ) {
                 output.append("  </resource>\n");
+              }
               output.append("  <resource order=\"" + permOrder + "\" public=\"" +
                             publicAcc + "\">\n");
               output.append("    <resourceIdentifier>" + docurl +
                             "</resourceIdentifier>\n");
               permOrder_prev = permOrder;
+            }
             // close </allow> or </deny> tag then open new one
             if ( permission != perm_prev ||
                  (endTime == null) && (end_prev != null) ||
                  (beginTime == null) && (begin_prev != null) ||
                  endTime != null && !endTime.equals(end_prev)  ||
                  beginTime != null && !beginTime.equals(begin_prev) ||
                  ticketCount != ticket_prev )  {
               output.append(outTemp.toString());
               outTemp = new StringBuffer();
               principalArr.removeAllElements();
               output.append("    <" + permType + ">\n");
+            }
             // put all principals here for the same
             // permission, duration and ticket_count
             if ( !principalArr.contains(principal) ) {
               principalArr.addElement(principal);
               output.append("      <principal>" + principal + "</principal>\n");
+            }
             // prepare <permission> tags, <duration> and <ticketCount>
             // if any to put within <allow> (<deny>) by next cicle
             if ( permission != perm_prev ||
                  (endTime == null) && (end_prev != null) ||
                  (beginTime == null) && (begin_prev != null) ||
                  endTime != null && !endTime.equals(end_prev)  ||
                  beginTime != null && !beginTime.equals(begin_prev) ||
                  ticketCount != ticket_prev )  {
               if ( (permission & READ) != 0 ) {
                 outTemp.append("      <permission>read</permission>\n");
+              }
               if ( (permission & WRITE) != 0 ) {
                 outTemp.append("      <permission>write</permission>\n");
+              }
               if ( (permission & ALL) != 0 ) {
                 outTemp.append("      <permission>all</permission>\n");
+              }
               if ( (beginTime != null) || (endTime != null) ) {
                 outTemp.append("      <duration>" + beginTime + " " + endTime +
                               "</duration>\n");
+              }
               if ( ticketCount > 0 ) {
                 outTemp.append("      <ticketCount>" + ticketCount +
                               "</ticketCount>\n");
+              }
               outTemp.append("    </" + permType + ">\n");
               perm_prev = permission;
               ticket_prev = ticketCount;
               begin_prev = beginTime;
               end_prev = endTime;
+            }
             hasRows = rs.next();
+          }
         } catch (MalformedURLException e) {
           throw new SAXException(e.getMessage());
           // close <allow> or <deny> if anything left in outTemp var
           output.append(outTemp.toString());
           // If there are no any acl info for @docid accessible by @user/@group,
           // extract only the following information
           if ( permOrder.equals("") ) {
             output.append("  <resource public=\"" + publicAcc + "\">\n");
             output.append("    <resourceIdentifier>" + docurl +
                           "</resourceIdentifier>\n");
+          }
           // always close them
           output.append("  </resource>\n");
           output.append("</acl>\n");
           pstmt.close();
           return output.toString();
         } catch (SQLException e) {
           throw new
           SQLException("AccessControlList.getACL(). " + e.getMessage());
+        }
+      }
+      }
       /* Check if @user is owner of @docid from db conn. */
       private boolean isOwned(String docid, String user) throws SQLException {
         PreparedStatement pstmt;
         pstmt = conn.prepareStatement("SELECT 'x' FROM xml_documents " +
                                       "WHERE docid LIKE ? " +
                                       "AND user_owner LIKE ?");
         pstmt.setString(1, docid);
         pstmt.setString(2, user);
         pstmt.execute();
         ResultSet rs = pstmt.getResultSet();
         boolean hasRow = rs.next();
         return hasRow;
+      }
       /* Get the flag for public "read" access for @docid from db conn. */
       private String getPublicAccess(String docid) throws SQLException {
         int publicAcc = 0;
         PreparedStatement pstmt;
         pstmt = conn.prepareStatement("SELECT public_access FROM xml_documents " +
                                       "WHERE docid LIKE ?");
         pstmt.setString(1, docid);
         pstmt.execute();
         ResultSet rs = pstmt.getResultSet();
         boolean hasRow = rs.next();
         if ( hasRow ) {
           publicAcc = rs.getInt(1);
+        }
         return (publicAcc == 1) ? "yes" : "no";
+      }
       /* Get SystemID for @publicID from Metacat DB Catalog. */
       private String getSystemID(String publicID) throws SQLException {
         String systemID = "";
         PreparedStatement pstmt;
         pstmt = conn.prepareStatement("SELECT system_id FROM xml_catalog " +
                                       "WHERE entry_type = 'DTD' " +
                                       "AND public_id LIKE ?");
         pstmt.setString(1, publicID);
         pstmt.execute();
         ResultSet rs = pstmt.getResultSet();
         boolean hasRow = rs.next();
         if ( hasRow ) {
           systemID = rs.getString(1);
+        }
         return systemID;
+      }
+    }

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Revision 688

Added by bojilova about 23 years ago