code: public static String convertToClob(final String varchar) {
        int startIndex = 0;
        int endIndex = Math.min(startIndex + 4000, varchar.length());
        final StringBuilder clobs = new StringBuilder("TO_CLOB('").append(
              varchar.substring(startIndex, endIndex)).append("')");
        while (endIndex < varchar.length()) {
           startIndex = endIndex;
           endIndex = Math.min(startIndex + 4000, varchar.length());
           clobs.append(" || TO_CLOB('").append(varchar.substring(startIndex, endIndex)).append("')");
        }
        return clobs.toString();
     }
docs: Generates the SQL to convert the given string to a CLOB.
  
  @param varchar
  the value to convert.
  @return the SQL to convert the string to a CLOB.