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The NetCDF-Java Library is a Java interface to NetCDF files, as well as to many other types of scientific data formats.

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/*
 * Copyright 1998-2009 University Corporation for Atmospheric Research/Unidata
 *
 * Portions of this software were developed by the Unidata Program at the
 * University Corporation for Atmospheric Research.
 *
 * Access and use of this software shall impose the following obligations
 * and understandings on the user. The user is granted the right, without
 * any fee or cost, to use, copy, modify, alter, enhance and distribute
 * this software, and any derivative works thereof, and its supporting
 * documentation for any purpose whatsoever, provided that this entire
 * notice appears in all copies of the software, derivative works and
 * supporting documentation.  Further, UCAR requests that the user credit
 * UCAR/Unidata in any publications that result from the use of this
 * software or in any product that includes this software. The names UCAR
 * and/or Unidata, however, may not be used in any advertising or publicity
 * to endorse or promote any products or commercial entity unless specific
 * written permission is obtained from UCAR/Unidata. The user also
 * understands that UCAR/Unidata is not obligated to provide the user with
 * any support, consulting, training or assistance of any kind with regard
 * to the use, operation and performance of this software nor to provide
 * the user with any updates, revisions, new versions or "bug fixes."
 *
 * THIS SOFTWARE IS PROVIDED BY UCAR/UNIDATA "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL UCAR/UNIDATA BE LIABLE FOR ANY SPECIAL,
 * INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 * FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 * NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE ACCESS, USE OR PERFORMANCE OF THIS SOFTWARE.
 */

package ucar.nc2.util;

import ucar.unidata.util.StringUtil;

import java.io.*;
import java.util.*;
import java.net.URL;

/**
 * Utility class to read and parse a fixed length table.
 * Each line of the table becomes a "Record". Each Record has a set of Fields described by the format string.
 *
 
    List recs = TableParser.readTable(is, "3,15,46,54,60d,67d,73d", 50000);
    for (TableParser.Record record : recs) {
      Station s = new Station();
      s.id = "K" + record.get(0);
      s.name = record.get(2) + " " + record.get(3);
      s.lat = (Double) record.get(4) * .01;
      s.lon = (Double) record.get(5) * .01;
      s.elev = (Double) record.get(6);

      stationTableHash.put(s.id, s);
      if (showStations) System.out.println(" station= " + s);
    }

Example Table:
TLX      000001 OKLAHOMA_CITY/Norman             OK US  3532  -9727   370  0 NWS
AMA      000313 AMARILLO/Amarillo                TX US  3523 -10170  1093  0 NWS
HGX      000378 HOUSTON/GALVESTON/Dickinson      TX US  2947  -9507     5  0 NWS
MLB      000302 MELBOURNE/Melbourne              FL US  2810  -8065    11  0 NWS

 format:
 "3,15,54,60d,67d,73d"

 grammer:
  format = {field,}
  field = endPos type
  endPos = ending pos in the line, 0 based, exclusive, ie String.substring(start, end)
  type = i=integer, d=double else String
  field[0] goes from [0, endPos[0])
  field[i] goes from [endPos[i-1] to endPos[i])



 *
 * @author caron
 */
public class TableParser {

  /**
   * Reads a URL or file in as a table.
   *
   * @param urlString starts with http, read URL contenets, else read file.
   * @see #readTable(InputStream ios, String format, int maxLines)
   * @param format describe format of each line.
   * @param maxLines maximum number of lines to parse, set to < 0 to read all
   * @return List of TableParser.Record
   * @throws IOException on read error
   * @throws NumberFormatException  on parse number error
   */
  static public List readTable(String urlString, String format, int maxLines) throws IOException, NumberFormatException {

    InputStream ios;
    if (urlString.startsWith("http:")) {
      URL url = new URL(urlString);
      ios = url.openStream();
    } else {
      ios = new FileInputStream(urlString);
     }
    
    return readTable( ios, format, maxLines);
  }

  /**
   * Reads an input stream, containing lines of ascii in fixed width format.
   * Breaks each line into a set of Fields (space or comma delimited) which may be String, integer or double.
   *
   * @param ios the input stream
   * @param format describe format of each line.
   * @param maxLines maximum number of lines to parse, set to < 0 to read all
   * @return List of TableParser.Record
   * @throws IOException on read error
   * @throws NumberFormatException  on parse number error
   */
  static public List readTable(InputStream ios, String format, int maxLines) throws IOException, NumberFormatException {
    List fields = new ArrayList();

    int start = 0;
    StringTokenizer stoker = new StringTokenizer( format, " ,");
    while (stoker.hasMoreTokens()) {
      String tok = stoker.nextToken();
      // see what type
      Class type = String.class;
      char last = tok.charAt(tok.length()-1);
      if (last == 'i') type = int.class;
      if (last == 'd') type = double.class;
      if (type != String.class) tok = tok.substring(0, tok.length()-1);

      int end = Integer.parseInt( tok);
      fields.add( new Field( start, end, type));
      start = end;
    }

    List records = new ArrayList();

    BufferedReader dataIS = new BufferedReader(new InputStreamReader(ios));
    int count = 0;
    while ((maxLines < 0) || (count < maxLines)) {
      String line = dataIS.readLine();
      if (line == null) break;
      if (line.startsWith("#")) continue;
      if (line.trim().length() == 0) continue;
      Record r = Record.make( line, fields);
      if (r != null)
        records.add(r);
      count++;
    }

    dataIS.close();
    return records;
  }

  /**
   * Describes one field in the record.
   */
  static private class Field {
    int start, end;
    Class type;

    Field (int start, int end, Class type) {
      this.start = start;
      this.end = end;
      this.type = type;
    }

    Object parse( String line) throws NumberFormatException {
      String svalue = (end > line.length()) ? line.substring(start) : line.substring(start, end);
      //System.out.printf("  [%d,%d) = %s %n",start, end, svalue);

      if (type == String.class)
        return svalue;

      try {
        svalue = StringUtil.remove(svalue,' ');
        if (type == double.class)
          return new Double( svalue);
        if (type == int.class)
          return new Integer( svalue);

      } catch (NumberFormatException e) {
        System.out.printf("  [%d,%d) = <%s> %n",start, end, svalue);
        throw e;
      }

      return null;
    }

  }

  /**
   * A set of values for one line.
   */
  static public class Record {
    private List values = new ArrayList();

    static Record make( String line, List fields) {
      try {
        Record r = new Record();
        for (Object field : fields) {
          Field f = (Field) field;
          r.values.add(f.parse(line));
        }
        return r;
      } catch (NumberFormatException e) {
        System.out.printf("Bad line=%s %n",line);
        return null;
      }
    }

    public int nfields() { return values.size(); }

    /**
     * Get the kth value of this record. Will be a String, Double, or Integer. 
     * @param k which one
     * @return object
     */
    public Object get(int k) { return values.get(k); }
  }

  ////////////////////////////////////////////////////////////////////////////////////
  static String testName = "C:/data/station/adde/STNDB.TXT";
  //static String testName = "M:/temp/STNDB.TXT";
  static String testName2 = "http://localhost:8080/test/STNDB.TXT";
  static String testName3 = "C:/dev/thredds/cdm/src/main/resources/resources/nj22/tables/nexrad.tbl";

  static public void main( String[] args) throws IOException {
    List recs = TableParser.readTable(testName3, "3,15,54,60d,67d,73d", 50000);
    for (int i = 0; i < recs.size(); i++) {
      Record record = (Record) recs.get(i);
      for (int j = 0; j < record.values.size(); j++) {
        Object s = record.values.get(j);
        System.out.print(" "+s.toString());
      }
      System.out.println();
    }
  }
}
    

    

    

            

    

            



    
    






    
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