Remove/collapse multiple newline characters. : String Format « Data Type « Java Tutorial

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 * Licensed to the Apache Software Foundation (ASF) under one
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 * distributed with this work for additional information
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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
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 * KIND, either express or implied.  See the License for the
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 */


/**

 *
 *  @author <a href="mailto:jvanzyl@apache.org">Jason van Zyl</a>
 *  @author <a href="mailto:dlr@finemaltcoding.com">Daniel Rall</a>
 *  @version $Id: StringUtils.java 685685 2008-08-13 21:43:27Z nbubna $
 */
public class Main {
  /**
   * Remove/collapse multiple newline characters.
   *
   * @param argStr string to collapse newlines in.
   * @return String
   */
  public static String collapseNewlines(String argStr)
  {
      char last = argStr.charAt(0);
      StringBuffer argBuf = new StringBuffer();

      for (int cIdx = 0 ; cIdx < argStr.length(); cIdx++)
      {
          char ch = argStr.charAt(cIdx);
          if (ch != '\n' || last != '\n')
          {
              argBuf.append(ch);
              last = ch;
          }
      }

      return argBuf.toString();
  }
}