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 * Ricebridge "Open Source API" policy; Ricebridge grants use of this
 * copyrighted work under the terms of a BSD-style license only. See
 * http://www.opensource.org/licenses/bsd-license.php for more
 * information.
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 * modification, are permitted provided that the following conditions
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 *  notice, this list of conditions and the following disclaimer.
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 *  - Redistributions in binary form must reproduce the above
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 *  disclaimer in the documentation and/or other materials provided
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package com.ricebridge.csvman;


import org.jostraca.util.Internal;

import java.util.List;


/** Simple implementation of {@link LineProvider} that provides data lines for saving
 *  from a <code>List</code> of <code>String[]</code> arrays.
 *    <p>The easiest way to save your CSV data using this format is to use the
 *  {@link CsvManager#save(Object,List) CsvManager.save} method.</p>
 *    <p>This <code>LineProvider</code> is a good one to use as a template for 
 *  your own custom <code>LineProviders</code>. 
 *    <p><code>BasicLineProvider</code> is designed to be subclassed. You can change
 *  the default implementation by calling the 
 *  {@link com.ricebridge.csvman.CsvManagerStore#setBasicLineProviderClass CsvManagerStore.setBasicLineProviderClass}
 *  method, and providing a subclass of <code>BasicLineProvider</code>. {@link CsvManagerStore} can be accessed 
 *  using {@link CsvManager#getCsvManagerStore}.</p>
 *    <p>The <b><a href="BasicLineProvider.java.html">Source Code</a></b> of this Java class 
 *  is available under a <a href="http://www.opensource.org/licenses/bsd-license.php">BSD-style license</a>.</p>
 *
 *  @see LineProvider
 *  @see CustomLineProvider
 *  @see ResultSetLineProvider 
 *  @see AsListsLineProvider 
 *  @see TableModelLineProvider 
 *  @see BeanLineProvider 
 */
public class BasicLineProvider extends CustomLineProvider {

  // protected instance

  /** <code>List</code> of <code>String[]</code> arrays. */
  protected List iData = null;

  /** Index of current line in <code>List</code>. */
  protected long iLineIndex = 0;



  
  // constructors

  /** Create uninitialised for use with {@link #setData setData}. */
  public BasicLineProvider() {
    // init with setData
  }


  /** Create with data lines as <code>List</code> of <code>String[]</code> arrays. 
   *  @param pData list of lines
   */
  public BasicLineProvider( List pData ) {
    setData( iData );
  }




  // CustomLineProvider methods

  /** Handle start of saving process by reseting line index. */
  protected void startProcessImpl() throws Exception {
    iLineIndex = 0;
  }


  /** Return <code>true</code> if line index is less than number of data lines in list. */
  protected boolean hasNextLineImpl() throws Exception {
    return iLineIndex < iData.size();
  }


  /* Return next data line from list. */
  protected String[] nextLineImpl() throws Exception {
    Object   lineobj = null;
    String[] line    = null;
    try {
      lineobj = iData.get( (int) iLineIndex );
      line = (String[]) lineobj;
      iLineIndex++;
      return line;
    }
    catch( ClassCastException cce ) {
      throw new CsvManagerException( CsvManagerException.CODE_cce_list_line, 
                                     new String[] {"index",String.valueOf(iLineIndex), "expected","String[]", 
                                                   "found", null==lineobj?"null":lineobj.getClass().getName()+":"+lineobj  }  );
    }
  }




  // public methods

  /** Set data lines to save as <code>List</code> of <code>String[]</code> arrays. */
  public void setData( List pData ) {
    iData = (List) Internal.null_arg( pData );
  }

}