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I am having an issue while parsing a CSV file. It is only 2 rows of data with a comma separating them. Row one is a date and row 2 is a value. The date field will always have dates in it but sometimes the value is blank (or null?). When it gets to the null value I get a StringIndexOutOfBoundsException and the app crashes. I am logging each loop and can see the data but as soon as I get to a null value it stops looping and gives the error. If there are no null values then it works perfect. Here is my code:

        BufferedReader buf = new BufferedReader(new StringReader(file));
        String line = null;
        while ((line = buf.readLine()) != null) {
            try {
                String date = null, value = null;
                String[] RowData = line.split(",");
                date = RowData[0];
                value = RowData[1]; (this is the row it crashes on)

This is what the CSV looks like:

2011-08-28 09:16,8.23

2011-08-28 09:15,8.24

2011-08-28 09:14,8.26

2011-08-28 09:13,8.34

2011-08-28 09:12,

2011-08-28 09:11,10.72

2011-08-28 09:10,

2011-08-28 09:09,

the value at 09:13 is the last thing in logcat before I get the error.

This fixed it:

                if(RowData.length == 2) {
                    date = RowData[0];
                    value = RowData[1];
                } else {
                    date = RowData[0];
                    value = "0";
                }

I wrote a 0 in the value field so later processes will not choke on the null value. Thanks for all your help guys!

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5 Answers 5

Reset to default
2

You want to do this or something like it:

String date = null, value = null;
String[] RowData = line.split(",");
date = RowData[0];

if(RowData.length ==2)value = RowData[1]; (this is the row it crashes on)

Or some variation of it e.g. if(RowData.length < 2) dont attempt to read the value. Its a pretty standard thing - if you ask an array for an index of a value it doesn't have Java will crash.

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2 Comments

I've tried all kinds of variations and it still crashes. I've tried stuff like if(RowData.length < 2) {value = "0";} else {value = RowData[1];} As usual I'm probably missing something simple lol.
I had to put the if statement before the date = RowData[0]; Thanks!
2

Why write your own CSV parsing when you could use a library that has already been written which will do it for you? Perhaps OpenCSV would help you achieve your CSV parsing goal.

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3 Comments

Because I don't want an entire library when a few lines a code does what I need. I just cant get it to skip null values.
Use ProGuard to strip out any unused classes at compile time.
I fixed it using a simple if statement. I just wasn't sure what to check. I was checking the string that I was trying to set instead of the entire RowData. Thanks for the suggestion anyways. I had looked into that a while back when i first wrote the code but I decided to just kill the loop after the first null field and dump the existing data to a DB. I finally got back around to it and now it is fixed :)
1

Check the length of RowData before you try to access it. It looks like split() is returning an array with a single object but you're trying to access the second object, which is indeed out of bounds.

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1 Comment

I updated my question above to include the section of the CSV file that is causing the crash. The line is not null but the second object is sometimes. I have tried different variations of checking for null along with if statements but it always if there is nothing after the comma.
1 
public class CityParser {
    DocumentBuilderFactory factory;
    DocumentBuilder builder;
    Document doc;

    Element ele;

    int mediaThumbnailCount;`enter code here`
    boolean urlflag;
    CityListBean objBean = null;

    Vector<CityListBean> vecCityList;

    public CityParser() {

    }

    public Vector<CityListBean> getCityData() {

        vecCityList = new Vector<CityListBean>();
        try {
            HttpClient httpClient = new DefaultHttpClient();
            HttpContext localContext = new BasicHttpContext();
            HttpGet httpGet = new HttpGet(
                    "http://heresmyparty.com/cms/index.php?option=com_chronocontact&chronoformname=add_event_form_download");
            HttpResponse response = httpClient.execute(httpGet, localContext);
            // String result = "";

            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    response.getEntity().getContent()));

            CSVReader csvreader = new CSVReader(reader);
            String[] nextLine;
            while ((nextLine = csvreader.readNext()) != null) {

                CityListBean objcitylist = new CityListBean();
                // nextLine[] is an array of values from the line
                objcitylist.setText_title(nextLine[5]);
                objcitylist.setText_host(nextLine[6]);
                objcitylist.setText_price(nextLine[7]);
                objcitylist.setDate(nextLine[8]);
                objcitylist.setText_venue(nextLine[11]);
                objcitylist.setAddress(nextLine[12]);
                objcitylist.setLatitude(nextLine[13]);
                objcitylist.setLongitude(nextLine[14]);
                objcitylist.setFile(nextLine[15]);
                objcitylist.setText_description(nextLine[16]);
                objcitylist.setCity(nextLine[17]);
                vecCityList.addElement(objcitylist);

            }


              /*for (int i = 0; i < vecCityList.size(); i++) { CityListBean
              objcity = (CityListBean) vecCityList.get(i);

              System.out.println("Cf_id : " + objcity.getCityName());
              System.out.println("-----------------------------------"); }*/


        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return vecCityList;
    }
}

==========================================================================================

public class CSVReader {

    private BufferedReader br;

    private boolean hasNext = true;

    private char separator;

    private char quotechar;

    private int skipLines;

    private boolean linesSkiped;


    public static final char DEFAULT_SEPARATOR = ',';

    public static final char DEFAULT_QUOTE_CHARACTER = '"';

    public static final int DEFAULT_SKIP_LINES = 0;

    public CSVReader(Reader reader) {
        this(reader, DEFAULT_SEPARATOR, DEFAULT_QUOTE_CHARACTER,
            DEFAULT_SKIP_LINES);
    }

    public CSVReader(Reader reader, char separator, char quotechar, int line) {
        this.br = new BufferedReader(reader);
        this.separator = separator;
        this.quotechar = quotechar;
        this.skipLines = line;
    }

    public String[] readNext() throws IOException {

        String nextLine = getNextLine();
        return hasNext ? parseLine(nextLine) : null;
    }

    private String getNextLine() throws IOException {
        if (!this.linesSkiped) {
            for (int i = 0; i < skipLines; i++) {
                br.readLine();
            }
            this.linesSkiped = true;
        }
        String nextLine = br.readLine();
        if (nextLine == null) {
            hasNext = false;
        }
        return hasNext ? nextLine : null;
    }

    private String[] parseLine(String nextLine) throws IOException {

        if (nextLine == null) {
            return null;
        }

        List<String> tokensOnThisLine = new ArrayList<String>();
        StringBuffer sb = new StringBuffer();
        boolean inQuotes = false;
        do {
                if (inQuotes) {
                // continuing a quoted section, reappend newline
                sb.append("\n");
                nextLine = getNextLine();
                if (nextLine == null)
                    break;
            }
            for (int i = 0; i < nextLine.length(); i++) {

                char c = nextLine.charAt(i);
                if (c == quotechar) {
                        // this gets complex... the quote may end a quoted block, or escape another quote.
                        // do a 1-char lookahead:
                        if( inQuotes  // we are in quotes, therefore there can be escaped quotes in here.
                            && nextLine.length() > (i+1)  // there is indeed another character to check.
                            && nextLine.charAt(i+1) == quotechar ){ // ..and that char. is a quote also.
                                // we have two quote chars in a row == one quote char, so consume them both and
                                // put one on the token. we do *not* exit the quoted text.
                                sb.append(nextLine.charAt(i+1));
                                i++;
                        }else{
                                inQuotes = !inQuotes;
                                // the tricky case of an embedded quote in the middle: a,bc"d"ef,g
                                if(i>2 //not on the begining of the line
                                                && nextLine.charAt(i-1) != this.separator //not at the begining of an escape sequence
                                                && nextLine.length()>(i+1) &&
                                                nextLine.charAt(i+1) != this.separator //not at the     end of an escape sequence
                                ){
                                        sb.append(c);
                                }
                        }
                } else if (c == separator && !inQuotes) {
                    tokensOnThisLine.add(sb.toString());
                    sb = new StringBuffer(); // start work on next token
                } else {
                    sb.append(c);
                }
            }
        } while (inQuotes);
        tokensOnThisLine.add(sb.toString());
        return (String[]) tokensOnThisLine.toArray(new String[0]);

    }

    public void close() throws IOException{
        br.close();
    }

}
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Comments

0

Have you tried to check first

if (RowData[1]!=null) or possibly if (RowData[1]!="")

I don't see why that would cause your app to crash though, it should just set value to null or ""

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1 Comment

Thanks, I already fixed it but it was crashing because the part of the app that was causing it to actually crash would not accept null strings.

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