/*

  * Copyright (c) 2006 - 2011 Michael Schierl

  * 

  * All rights reserved.

  * 

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  * 

  * - Redistributions of source code must retain the above copyright notice,

  *   this list of conditions and the following disclaimer.

  *   

  * - Redistributions in binary form must reproduce the above copyright

  *   notice, this list of conditions and the following disclaimer in the

  *   documentation and/or other materials provided with the distribution.

  *   

  * - Neither name of the copyright holders nor the names of its

  *   contributors may be used to endorse or promote products derived from

  *   this software without specific prior written permission.

  *   

  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND THE CONTRIBUTORS

  * "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 THE COPYRIGHT

  * HOLDERS OR THE CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,

  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,

  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS

  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND

  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR

  * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE

  * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

  */

 package net.sf.jmatchparser.util.csv;

 import java.io.IOException;

 import java.util.Arrays;

 import java.util.HashMap;

 import java.util.Map;

 /**

  * Abstract base class to read data from several CSV-like file formats.

  */

 public abstract class AbstractCSVReader {

         /**

          * Read a line from the CSV file, and pass its columns into a {@link Map}

          * using the given keys/headers.

          * 

          * @param <T>

          *            Type of the keys

          * @param headers

          *            Keys/Headers

          * @param includeEmptyColumns

          *            Whether to include empty column values in the map

          */

         public final <T> Map<T, String> read(T[] headers, boolean includeEmptyColumns) throws IOException {

                 Map<T, String> result = new HashMap<T, String>();

                 String[] tempResult = read(headers.length);

                 for (int i = 0; i < tempResult.length; i++) {

                         if (tempResult[i].length() > 0 || includeEmptyColumns)

                                 result.put(headers[i], tempResult[i]);

                 }

                 return result;

         }

         /**

          * Read a line from the CSV file and pad it to the given number of columns

          * with empty strings.

          * 

          * @param columnCount

          *            Desired number of columns

          * @return The padded line

          * @throws IOException

          *             if there are too many columns in the original line.

          */

         public final String[] read(int columnCount) throws IOException {

                 String[] tempResult = read();

                 if (tempResult.length == columnCount)

                         return tempResult;

                 if (tempResult.length > columnCount)

                         throw new IOException("Too many columns: " + Arrays.asList(tempResult));

                 String[] result = new String[columnCount];

                 System.arraycopy(tempResult, 0, result, 0, tempResult.length);

                 Arrays.fill(result, tempResult.length + 1, result.length, "");

                 return result;

         }

         /**

          * Write the complete content of this reader to the given

          * {@link AbstractCSVWriter} and close both reader and writer.

          * 

          * @param writer

          *            The writer to write to

          */

         public void writeTo(AbstractCSVWriter writer) throws IOException {

                 String[] record;

                 while ((record = read()) != null)

                         writer.write(record);

                 close();

                 writer.close();

         }

         /**

          * Read a line from the CSV file.

          */

         public abstract String[] read() throws IOException;

         /**

          * Close this reader.

          */

         public abstract void close() throws IOException;

 }