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I have a program that reads in a CSV file and stores the first and last lines as a JSONObject . My current implementation is skipping over the last line and reading in a null value as the data object.

What's the correct way to create/save a CSV file as to eliminate any white space or null values?

   TIME_STAMP,TOTAL,APPLES,ORANGES,PEARS,GRAPES,TANGERINES,PINEAPPLES,CARROTS,UNKNOWN 
    7/1/2015 4:00,19474,1736,275,8366,5352,3003,393,349,
String firstLine = "";
String lastLine = "";
int count = 0;
if(reader != null){
    String aux = "";
    String lastLineMinusOne = "";
    while ((aux = reader.readLine()) != null) {
        if(count == 0)firstLine = aux;
            lastLineMinusOne = lastLine;
            lastLine = aux;
            count ++;
        logger.info("Count = " + count);             
        String[] columns = firstLine.split(",");
        String[] data = lastLine.split(",");
        logger.info(firstLine);
        logger.info(lastLine);
    2015-09-28 13:41:42,370 [ajp-0.0.0.0-8009-2] INFO  com.ChartData - Count = 3
    2015-09-28 13:23:27,745 [ajp-0.0.0.0-8009-3] INFO  com.ChartData - TIME_STAMP,TOTAL,APPLES,ORANGES,PEARS,GRAPES,TANGERINES,PINEAPPLES,CARROTS,UNKNOWN
    2015-09-28 13:23:27,745 [ajp-0.0.0.0-8009-3] INFO  com.ChartData -
Error
java.lang.ArrayIndexOutOfBoundsException: 10
    at com.ChartData.getCSV(ChartData.java:75)
Line 75 -> jObject.put("val", data[i]);
while ((aux = reader.readLine()) != null) {
    String auxTrimmed = aux.replaceAll("(?m)^[ \t]*\r?\n", "");
    // more code
If you experience this problem always, just ignore last line:
String[] data = lastLineMinusOne.split(",");
logger.info(lastLineMinusOne);
Usually, using some good library is a best way, if you do it not for education. CSV looks simple, until you face text in quotes, escape characters, different line endings and so on. 
In your case you can use apache commons.csv
   <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>commons-csv</artifactId>
        <version>1.0</version>
   </dependency>
and short usage example, note withIgnoreEmptyLines(true):
final CSVFormat format = CSVFormat.DEFAULT
                .withIgnoreEmptyLines(true)
                .withDelimiter(',');
CSVParser parser = CSVParser.parse(file, Charset.forName("UTF-8"), format);
Iterator<CSVRecord> iterator = parser.iterator();
        
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