package com.opencsv.stream.reader;
   
   import com.opencsv.ICSVParser;
   
   import java.io.BufferedReader;
   import java.io.IOException;
   
   /**
    * This class was created for
   * <a href="https://sourceforge.net/p/opencsv/bugs/106/">issue #106</a>
   * where carriage returns were being removed.
   * This class allows the user to determine if they wish to keep or
   * remove them from the data being read.
   *
   * @author Scott Conway
   * @since 3.3
   */
  
  public class LineReader {
      private final BufferedReader reader;
      private final boolean keepCarriageReturns;
  
      /**
       * LineReader constructor.
       *
       * @param reader              Reader that data will be read from.
       * @param keepCarriageReturns True if carriage returns should remain in the data, false to remove them.
       */
      public LineReader(BufferedReader reader, boolean keepCarriageReturns) {
          this.reader = reader;
          this.keepCarriageReturns = keepCarriageReturns;
      }
  
      /**
       * Reads the next line from the Reader.
       *
       * @return Line read from reader.
       * @throws IOException On error from BufferedReader
       */
      public String readLine() throws IOException {
          return keepCarriageReturns ? readUntilNewline() : reader.readLine();
      }
  
      private String readUntilNewline() throws IOException {
          StringBuilder sb = new StringBuilder(ICSVParser.INITIAL_READ_SIZE);
          for (int c = reader.read(); c > -1 && c != '\n'; c = reader.read()) {
              sb.append((char) c);
          }
  
          return sb.length() > 0 ? sb.toString() : null;
      }
  }