icalparser.java

The program is used for the calculations of the day , week , month on the calendar .

            // ignore leading blank lines
          } else {
            // Hmmm... should always start with this.
            if ( isParseStrict () ) {
              reportParseError ( new ParseError (
                ln, "Data found outside VCALENDAR block", line ) );
            }
          }
          break;

        case STATE_VCALENDAR:
          if ( lineUp.startsWith ( "BEGIN:VTIMEZONE" ) ) {
            state = STATE_VTIMEZONE;
            startLineNo = ln; // mark starting line number
            textLines.removeAllElements ();
            textLines.addElement ( line );
          } else if ( lineUp.startsWith ( "BEGIN:VEVENT" ) ) {
            state = STATE_VEVENT;
            startLineNo = ln; // mark starting line number
            textLines.removeAllElements ();
            textLines.addElement ( line );
          } else if ( lineUp.startsWith ( "BEGIN:VTODO" ) ) {
            state = STATE_VTODO;
            startLineNo = ln; // mark starting line number
            textLines.removeAllElements ();
            textLines.addElement ( line );
          } else if ( lineUp.startsWith ( "BEGIN:VJOURNAL" ) ) {
            state = STATE_VJOURNAL;
            startLineNo = ln; // mark starting line number
            textLines.removeAllElements ();
            textLines.addElement ( line );
          } else if ( lineUp.startsWith ( "BEGIN:VFREEBUSY" ) ) {
            state = STATE_VFREEBUSY;
            startLineNo = ln; // mark starting line number
            textLines.removeAllElements ();
            textLines.addElement ( line );
          } else if ( lineUp.startsWith ( "END:VCALENDAR" ) ) {
            state = STATE_DONE;
          } else if ( lineUp.startsWith ( "VERSION" ) ) {
            if ( icalVersion != null && isParseStrict() ) {
              // only one of these allowed
              reportParseError ( new ParseError (
                ln, "Only one VERSION token allowed", line ) );
            } else {
              try {
                icalVersion = new Property ( line, getParseMethod() );
              } catch ( ParseException e ) {
                reportParseError ( new ParseError (
                  ln, "Parse error in VERSION: " + e.toString(), line ) );
              }
            }
          } else if ( lineUp.startsWith ( "PRODID" ) ) {
            if ( prodId != null && isParseStrict() ) {
              // only one of these allowed
              reportParseError ( new ParseError (
                ln, "Only one PRODID token allowed", line ) );
            } else {
              try {
                prodId = new Property ( line, getParseMethod() );
              } catch ( ParseException e ) {
                reportParseError ( new ParseError (
                  ln, "Parse error in PRODID: " + e.toString(), line ) );
              }
            }
          } else if ( lineUp.startsWith ( "CALSCALE" ) ) {
            try {
              calscale = new Property ( line, getParseMethod() );
            } catch ( ParseException e ) {
              reportParseError ( new ParseError (
                ln, "Parse error in CALSCALE: " + e.toString(), line ) );
            }
          } else if ( lineUp.startsWith ( "METHOD" ) ) {
            try {
              method = new Property ( line, getParseMethod() );
            } catch ( ParseException e ) {
              reportParseError ( new ParseError (
                ln, "Parse error in CALSCALE: " + e.toString(), line ) );
            }
          } else {
            // what else could this be???
            if ( lineUp.trim().length() == 0 ) {
              // ignore blank lines
            } else if ( isParseStrict () ) {
              reportParseError ( new ParseError (
                ln, "Unrecognized data found in VCALENDAR block", line ) );
            }
          }
          break;

        case STATE_VTIMEZONE:
          textLines.addElement ( line );
          if ( lineUp.startsWith ( "END:VTIMEZONE" ) ) {
            state = STATE_VCALENDAR;
            Timezone timezone = new Timezone ( this, startLineNo, textLines );
            if ( timezone.isValid() ) {
              for ( int i = 0; i < dataStores.size(); i++ ) {
                DataStore ds = (DataStore) dataStores.elementAt ( i );
                ds.storeTimezone ( timezone );
              }
            }
            textLines.removeAllElements (); // truncate Vector
          }
          break;

        case STATE_VTODO:
          textLines.addElement ( line );
          if ( lineUp.startsWith ( "END:VTODO" ) ) {
            state = STATE_VCALENDAR;
            // Send the Todo object to all DataStore objects
            /*** TODO - not yet implemented
                 Uncomment this when Todo.java is implemented
            Todo todo = new Todo ( this, startLineNo, textLines );
            if ( todo.isValid() ) {
              for ( int i = 0; i < dataStores.size(); i++ ) {
                DataStore ds = (DataStore) dataStores.elementAt ( i );
                ds.storeTodo ( todo );
              }
            }
            ***/
            textLines.removeAllElements (); // truncate Vector
          }
          break;

        case STATE_VJOURNAL:
          textLines.addElement ( line );
          if ( lineUp.startsWith ( "END:VJOURNAL" ) ) {
            state = STATE_VCALENDAR;
            // Send the Journal object to all DataStore objects
            /*** TODO - not yet implemented
                 Uncomment this when Journal.java is implemented
            Journal journal = new Journal ( this, startLineNo, textLines );
            if ( journal.isValid() ) {
              for ( int i = 0; i < dataStores.size(); i++ ) {
                DataStore ds = (DataStore) dataStores.elementAt ( i );
                ds.storeJournal ( event );
              }
            }
            ***/
            textLines.removeAllElements (); // truncate Vector
          }
          break;

        case STATE_VEVENT:
          textLines.addElement ( line );
          if ( lineUp.startsWith ( "END:VEVENT" ) ) {
            state = STATE_VCALENDAR;
            Event event = new Event ( this, startLineNo, textLines );
            if ( event.isValid() ) {
              for ( int i = 0; i < dataStores.size(); i++ ) {
                DataStore ds = (DataStore) dataStores.elementAt ( i );
                ds.storeEvent ( event );
              }
            } else {
System.out.println ( "ERROR: Invalid VEVENT found" );
            }
            textLines.removeAllElements (); // truncate Vector
          }
          break;

        case STATE_VFREEBUSY:
          textLines.addElement ( line );
          if ( lineUp.startsWith ( "END:VFREEBUSY" ) ) {
            state = STATE_VCALENDAR;
            // Send the Freebusy object to all DataStore objects
            /*** TODO - not yet implemented
                 Uncomment this when Freebusy.java is implemented
            Freebusy fb = new Freebusy ( this, startLineNo, textLines );
            if ( fb.isValid() ) {
              for ( int i = 0; i < dataStores.size(); i++ ) {
                DataStore ds = (DataStore) dataStores.elementAt ( i );
                ds.storeFreebusy ( event );
              }
            }
            ***/
            textLines.removeAllElements (); // truncate Vector
          }
          break;

        case STATE_DONE:
          // should be nothing else after "END:VCALENDAR"
          if ( lineUp.trim().length() == 0 ) {
            // ignore blank lines at end of file
          } else if ( isParseStrict () ) {
            reportParseError ( new ParseError (
              ln, "Data found after END:VCALENDAR", line ) );
          }
          break;
      }
      if ( nextLine == null )
        done = true;
    }
    r.close ();

    // Make sure PRODID and VERSION were specified since they are
    // required
    if ( icalVersion == null && isParseStrict() ) {
      reportParseError ( new ParseError (
        ln, "No required VERSION attribute found", "n/a" ) );
    }
    if ( prodId == null && isParseStrict() ) {
      reportParseError ( new ParseError (
        ln, "No required PRODID attribute found", "n/a" ) );
    }

    // iCal data is now in line
    // TODO: split into event, todo, timezone and journal strings

    return noErrors;
  }

  public String toIcal ()
  {
    StringBuffer ret = new StringBuffer ( 1024 );
    ret.append ( "BEGIN:VCALENDAR" );
    ret.append ( CRLF );
    ret.append ( "VERSION:2.0" );
    ret.append ( CRLF );
    // Should we use the PRODID we parsed on input.  Since we are generating
    // output, I think we will use ours.
    // TODO: add version number in the following
    ret.append ( "PRODID:-//k5n.us//Java Calendar Tools//EN" );
    ret.append ( CRLF );

    // Include events
    Vector events = ((DataStore) getDataStoreAt ( 0 )).getAllEvents ();
    for ( int i = 0; i < events.size(); i++ ) {
      Event ev = (Event) events.elementAt ( i );
      ret.append ( ev.toIcal () );
    }

    ret.append ( "END:VCALENDAR" );
    ret.append ( CRLF );
    return ret.toString ();
  }



  // Test routine - will parse input string and then export back
  // into ical format.
  // Usage: java us.k5n.ical.IcalParser testfile.ics
  //   
  public static void main ( String args[] )
  {
    for ( int i = 0; i < args.length; i++ ) {
      java.io.File f = new java.io.File ( args[i] );
      IcalParser a = new IcalParser ( PARSE_STRICT );
      java.io.BufferedReader reader = null;
      if ( f.exists () ) {
        try {
          reader = new java.io.BufferedReader ( new java.io.FileReader ( f ) );
          a.parse ( reader );
        } catch ( IOException e ) {
          System.err.println ( "Error opening " + f + ": " + e );
          System.exit ( 1 );
        }
      } else {
        System.err.println ( "Usage: java IcalParser filename.ics" );
        System.exit ( 1 );
      }
      System.out.println ( "Filename:\n  " + args[i] );
      //System.out.println ( "\nFormatted output:\n\n" + a.toIcal () );
      Vector errors = a.getAllErrors ();
      for ( int j = 0; j < errors.size (); j++ ) {
        ParseError err = (ParseError) errors.elementAt ( j );
        System.out.println ( "Error # " + (j+1) + ":\n" + err.toString ( 2 ) );
      }
    }
  }
}