private void readHeaderFromFile( ucar.unidata.io.RandomAccessFile raFile )
          throws IOException
  {
    long pos = 0;
    raFile.seek( pos );

    // Read in first record.
    this.headerSizeInBytes = raFile.length() > this.headerSizeInBytesGuess ?
                             this.headerSizeInBytesGuess : (int) raFile.length();
    byte[] b = new byte[this.headerSizeInBytes];
    if ( raFile.read(b) != this.headerSizeInBytes ) throw new IOException( "Invalid DMSP file: could not read first " + this.headerSizeInBytes + " bytes.");
    String fullHeader = new String( b, CDM.utf8Charset);
    // Make sure header starts with the proper item.
    if ( ! fullHeader.startsWith( HeaderInfoTitle.FILE_ID.toString() ) )
    {
      throw new IOException( "Invalid DMSP file: header does not start with \"" + HeaderInfoTitle.FILE_ID.toString() + "\"." );
    }
    // Make sure header contains end-of-header marker.
    int endOfHeaderIndex = fullHeader.indexOf( HeaderInfoTitle.END_HEADER.toString() );
    if ( endOfHeaderIndex == -1 )
    {
      throw new IOException( "Invalid DMSP file: header does not end with \"" + HeaderInfoTitle.END_HEADER.toString() + "\"." );
    }

    // Drop the end-of-header marker and the line feed ('\n') proceeding it.
    header = fullHeader.substring( 0, endOfHeaderIndex - 1 ).split( "\n" );

    int lineSeperatorIndex = 0;
    String curHeaderLine = null;
    String curHeaderTitle = null;
    String curHeaderValue = null;
    for (String aHeader : this.header) {
      curHeaderLine = aHeader.trim();
      lineSeperatorIndex = curHeaderLine.indexOf(':');
      if (lineSeperatorIndex == -1)
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no seperator <:>.");
      if (lineSeperatorIndex == 0)
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no title.");
      if (lineSeperatorIndex == curHeaderLine.length() - 1)
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no value.");

      curHeaderTitle = curHeaderLine.substring(0, lineSeperatorIndex).trim();
      curHeaderValue = curHeaderLine.substring(lineSeperatorIndex + 1).trim();
      if (curHeaderValue.equals(""))
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no value.");

      headerInfo.put(curHeaderTitle, curHeaderValue);
    }
  }
private void readHeaderFromFile( ucar.unidata.io.RandomAccessFile raFile )
          throws IOException
  {
    long pos = 0;
    raFile.seek( pos );

    
    this.headerSizeInBytes = raFile.length() > this.headerSizeInBytesGuess ?
                             this.headerSizeInBytesGuess : (int) raFile.length();
    byte[] b = new byte[this.headerSizeInBytes];
    if ( raFile.read(b) != this.headerSizeInBytes ) throw new IOException( "Invalid DMSP file: could not read first " + this.headerSizeInBytes + " bytes.");
    String fullHeader = new String( b, CDM.utf8Charset);
    
    if ( ! fullHeader.startsWith( HeaderInfoTitle.FILE_ID.toString() ) )
    {
      throw new IOException( "Invalid DMSP file: header does not start with \"" + HeaderInfoTitle.FILE_ID.toString() + "\"." );
    }
    
    int endOfHeaderIndex = fullHeader.indexOf( HeaderInfoTitle.END_HEADER.toString() );
    if ( endOfHeaderIndex == -1 )
    {
      throw new IOException( "Invalid DMSP file: header does not end with \"" + HeaderInfoTitle.END_HEADER.toString() + "\"." );
    }

    
    header = fullHeader.substring( 0, endOfHeaderIndex - 1 ).split( "\n" );

    int lineSeperatorIndex = 0;
    String curHeaderLine = null;
    String curHeaderTitle = null;
    String curHeaderValue = null;
    for (String aHeader : this.header) {
      curHeaderLine = aHeader.trim();
      lineSeperatorIndex = curHeaderLine.indexOf(':');
      if (lineSeperatorIndex == -1)
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no seperator <:>.");
      if (lineSeperatorIndex == 0)
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no title.");
      if (lineSeperatorIndex == curHeaderLine.length() - 1)
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no value.");

      curHeaderTitle = curHeaderLine.substring(0, lineSeperatorIndex).trim();
      curHeaderValue = curHeaderLine.substring(lineSeperatorIndex + 1).trim();
      if (curHeaderValue.equals(""))
        throw new IOException("Invalid DMSP file: header line <" + curHeaderLine + "> contains no value.");

      headerInfo.put(curHeaderTitle, curHeaderValue);
    }
  }
private void readHeaderFromFile ( ucar . unidata . io . RandomAccessFile raFile ) throws IOException { long pos = 0 ; raFile . seek ( pos ) ; // Read in first record. this . headerSizeInBytes = raFile . length ( ) > this . headerSizeInBytesGuess ? this . headerSizeInBytesGuess : ( int ) raFile . length ( ) ; byte [ ] b = new byte [ this . headerSizeInBytes ] ; if ( raFile . read ( b ) != this . headerSizeInBytes ) throw new IOException ( "Invalid DMSP file: could not read first " + this . headerSizeInBytes + " bytes." ) ; String fullHeader = new String ( b , CDM . utf8Charset ) ; // Make sure header starts with the proper item. if ( ! fullHeader . startsWith ( HeaderInfoTitle . FILE_ID . toString ( ) ) ) { throw new IOException ( "Invalid DMSP file: header does not start with \"" + HeaderInfoTitle . FILE_ID . toString ( ) + "\"." ) ; } // Make sure header contains end-of-header marker. int endOfHeaderIndex = fullHeader . indexOf ( HeaderInfoTitle . END_HEADER . toString ( ) ) ; if ( endOfHeaderIndex == - 1 ) { throw new IOException ( "Invalid DMSP file: header does not end with \"" + HeaderInfoTitle . END_HEADER . toString ( ) + "\"." ) ; } // Drop the end-of-header marker and the line feed ('\n') proceeding it. header = fullHeader . substring ( 0 , endOfHeaderIndex - 1 ) . split ( "\n" ) ; int lineSeperatorIndex = 0 ; String curHeaderLine = null ; String curHeaderTitle = null ; String curHeaderValue = null ; for ( String aHeader : this . header ) { curHeaderLine = aHeader . trim ( ) ; lineSeperatorIndex = curHeaderLine . indexOf ( ' ' ) ; if ( lineSeperatorIndex == - 1 ) throw new IOException ( "Invalid DMSP file: header line <" + curHeaderLine + "> contains no seperator <:>." ) ; if ( lineSeperatorIndex == 0 ) throw new IOException ( "Invalid DMSP file: header line <" + curHeaderLine + "> contains no title." ) ; if ( lineSeperatorIndex == curHeaderLine . length ( ) - 1 ) throw new IOException ( "Invalid DMSP file: header line <" + curHeaderLine + "> contains no value." ) ; curHeaderTitle = curHeaderLine . substring ( 0 , lineSeperatorIndex ) . trim ( ) ; curHeaderValue = curHeaderLine . substring ( lineSeperatorIndex + 1 ) . trim ( ) ; if ( curHeaderValue . equals ( "" ) ) throw new IOException ( "Invalid DMSP file: header line <" + curHeaderLine + "> contains no value." ) ; headerInfo . put ( curHeaderTitle , curHeaderValue ) ; } }
Read the header information from the file into name/value pairs.

@param raFile - the file to be read.
@throws IOException if any problems reading the file (or validating the file).
Read the header information from the file into name / value pairs .