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Java Scanner, No such element exception while reading mulitple lines

I am trying to read multiple line from a file using java scanner. Each line has strings separated using comma, but there is no comma at the end of line. My text file contains value like below
98792203000000005091,89065012012341234100000000000167,084952103900000015
98792203000000005091,89065012012341234100000000000167,084952103900000015
The scanner is throwing a no element exception, it works fine if I add a comma t the end of line, but the original file will not have a comma. How do I make work
Scanner sc = new Scanner(outPutFile);
int outputDataStart = Integer.parseInt(outputDataStartLine);
skipLines(sc, outputDataStart);
sc.useDelimiter(",");
while(sc.hasNext())
{
OutputVariables outputVariables = new OutputVariables();
outputVariables.setIccid(sc.next());
outputVariables.setImsi(sc.next());
outputVariables.setKey(sc.next());
outputVariables.setPIN1(sc.next());
outputVariables.setPUK1(sc.next());
outputVariables.setPIN2(sc.next());
outputVariables.setPUK2(sc.next());
outputVariables.setPINAdm(sc.next());
outputVariables.setAccount(sc.next());
outputVariables.setKIC(sc.next());
outputVariables.setKID(sc.next());
outputVariables.setKIK(sc.next());
outputVariables.setOPCKey(sc.next());
OutputVariableList.add(outputVariables);
}

Insteard of using sc.useDelimiter(",") use sc.useDelimiter(",|\\n") it would break by both , and new line

You're asking the scanner to parse more values from a line of text than there are values. This is happening because you're calling next() without first checking hasNext(). Since you've told it to use the comma as the delimeter, it's hitting the end of the line continuing on to the next line until it finds the next comma.
Consider this CSV:
A,B,C,D
If you call next() after you parse the "D", the scanner will throw a NoSuchElementException.
It is not clear what you're attempting to do. If you're attempting to convert what is effectively a CSV into an object, then your best bet would be to use the Scanner to read each line, and then a String.split() call to split that line into parts.
If you're trying to parse multiple lines into an object, you'll of course need to figure out where your boundary is -- every fifteen comma separated values? every three lines? -- and apply that logic while collecting your segments.
As a simplified example, consider this collection of lines:
A,B,C,D
E,F,G,H
I,J,K
You would first use the Scanner to read line-by-line, and then use split each line apart and create the individual objects. Notice the last line is malformed -- you'll need to trap for that and catch it to avoid the NoSuchElementException.
Scanner sc = new Scanner(file);
while(sc.hasNext()) {
String line = sc.next();
String[] parts = line.split(",");
if(parts.length != 4) {
System.err.println("Invalid line: " + line);
continue; // skip this record, it is bad
}
// create your object here from parts
Pojo example = new Pojo(parts[0], parts[1], parts[2], parts[3]);
// etc
}
Alternatively if you're just trying to create a single massive object -- eg all lines belong to the same record -- you could tell it to consider a newline as a delimeter in addition to a comma. That way, after you hit the last comma in the first line, you would call next() and it would parse until the end of the line; and then when you called next() again, it would parse starting on the next line until it reached a comma or the end of the line, whichever came first.

I suggest you to use BufferedReader
it has a method named readLine()
first read a String then through the string.split(",") you can get the array of String

Parse .csv File in java returns outofbounds exception

I have the following issue: I am trying to parse a .csv file in java, and store specifically 3 columns of it in a 2 Dimensional array. The Code for the method looks like this:
public static void parseFile(String filename) throws IOException{
FileReader readFile = new FileReader(filename);
BufferedReader buffer = new BufferedReader(readFile);
String line;
String[][] result = new String[10000][3];
String[] b = new String[6];
for(int i = 0; i<10000; i++){
while((line = buffer.readLine()) != null){
b = line.split(";",6);
System.out.println("ID: "+b[0]+" Title: "+b[3]+ "Description: "+b[4]); // Here is where the outofbounds exception occurs...
result[i][0] = b[0];
result[i][1] = b[3];
result[i][2] = b[4];
}
}
buffer.close();
}
I feel like I have to specify this: the .csv file is HUGE. It has 32 columns, and (almost) 10.000 entries (!).
When Parsing, I keep getting the following:
XXXXX CHUNKS OF SUCCESFULLY EXTRACTED CODE
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException:3
at ParseCSV.parseFile(ParseCSV.java:24)
at ParseCSV.main(ParseCSV.java:41)
However, I realized that SOME of the stuff in the file has a strange format e.g. some of the texts inside it for instance have newlines in them, but there is no newline character involved in any way. However, if I delete those blank lines manually, the output generated (before the error message is prompted) adds the stuff to the array up until the next blank line ...
Does anyone have an idea how to fix this? Any help would be greately appreciated...

Your first problem is that you probably have at least one blank line in your csv file. You need to replace:
b = line.split(";", 6);
with
b = line.split(";");
if(b.length() < 5){
System.err.println("Warning, line has only " + b.length() +
"entries, so skipping it:\n" + line);
continue;
}
If your input can legitimately have new lines or embedded semi-colons within your entries, that is a more complex parsing problem, and you are probably better off using a third-party parsing library, as there are several very good ones.
If your input is not supposed to have new lines in it, the problem probably is \r. Windows uses \r\n to represent a new line, while most other systems just use \n. If multiple people/programs edited your text file, it is entirely possible to end up with stray \r by themselves, which are not easily handled by most parsers.
A way to easily check if that's your problem is before you split your line, do
line = line.replace("\r","").
If this is a process you are repeating many times, you might need to consider using a Scanner (or library) instead to get more efficient text processing. Otherwise, you can make do with this.

When you have new lines in your CSV file, after this line
while((line = buffer.readLine()) != null){
variable line will have not a CSV line but just some text without ;
For example, if you have file
column1;column2;column
3 value
after first iteration variable line will have
column1;column2;column
after second iteration it will have
3 value
when you call "3 value".split(";",6) it will return array with one element. and later when you call b[3] it will throw exception.
CSV format has many small things, to implement which you will spend a lot of time. This is a good article about all possible csv examples
http://en.wikipedia.org/wiki/Comma-separated_values#Basic_rules_and_examples
I would recommend to you some ready CSV parsers like this
https://commons.apache.org/proper/commons-csv/apidocs/org/apache/commons/csv/CSVParser.html

String's split(pattern, limit) method returns an array sized to the number of tokens found up to the the number specified by the limit parameter. Limit is the maximum, not the minimum number of array elements returned.
"1,2,3" split with (",", 6) with return an array of 3 elements: "1", "2" and "3".
"1,2,3,4,5,6,7" will return 6 elements: "1", "2", "3", "4", "5" and ""6,7" The last element is goofy because the split method stopped splitting after 5 and returned the rest of the source string as the sixth element.
An empty line is represented as an empty string (""). Splitting "" will return an array of 1 element, the empty string.
In your case, the string array created here
String[] b = new String[6];
and assigned to b is replaced by the the array returned by
b = line.split(";",6);
and meets it's ultimate fate at the hands of the garbage collector unseen and unloved.
Worse, in the case of the empty lines, it's replaced by a one element array, so
System.out.println("ID: "+b[0]+" Title: "+b[3]+ "Description: "+b[4]);
blows up when trying to access b[3].
Suggested solution is to either
while((line = buffer.readLine()) != null){
if (line.length() != 0)
{
b = line.split(";",6);
System.out.println("ID: "+b[0]+" Title: "+b[3]+ "Description: "+b[4]); // Here is where the outofbounds exception occurs...
...
}
or (better because the previous could trip over a malformed line)
while((line = buffer.readLine()) != null){
b = line.split(";",6);
if (b.length() == 6)
{
System.out.println("ID: "+b[0]+" Title: "+b[3]+ "Description: "+b[4]); // Here is where the outofbounds exception occurs...
...
}
You might also want to think about the for loop around the while. I don't think it's doing you any good.
while((line = buffer.readLine()) != null)
is going to read every line in the file, so
for(int i = 0; i<10000; i++){
while((line = buffer.readLine()) != null){
is going to read every line in the file the first time. Then it going to have 9999 attempts to read the file, find nothing new, and exit the while loop.
You are not protected from reading more than 10000 elements because the while loop because the while loop will read a 10001th element and overrun your array if there are more than 10000 lines in the file. Look into replacing the big array with an arraylist or vector as they will size to fit your file.

Please check b.length>0 before accessing b[].

What's an elegant way to parse this text in java?

Disclaimer:
The parsing-problem described in here is very simple. This question does not simply ask for a way to achieve the parsing. - That's almost straightforward - Instead, it asks for an elegant way. That elegant way would probably be one which does not first read line-wise and then parse each line on its own, as this is obviously not necessary. However, is this elegant way possible with ready to use standard classes?
Question:
I have to parse text of the following form in java (there is more than these 3 records; records can have way more lines than these examples):
5
Dominik 3
Markus 3 2
Reiner 1 2
Samantha 4
Thomas 3
4
Babette 1 4
Diana 3 4
Magan 2
Thomas 2 4
The first number n is the number of lines in the record directly following. Each record consists of a name and then 0 to n integers.
I thought that using java.util.Scanner is a natural choice, but it leads to the nastiness that when using hasNextInt() and hasNext() to determine if a line is started, I can't distinguish if a read number is the header of the next record or it's the last number behind the last name of the previous record. Example from above:
...
Thomas 3
4
...
Here, I don't know how to tell if the 3 and the 4 is a header or belongs to the current line of Thomas.
Sure I can first read line by line, put them into another Scanner, and then read them again, but this effectively parses the whole data twice, which looks ugly to me. Is there a better way?
I would need something like a flag which tells me if a line break was encountered during the last delimiter skipping operation.

Read the file using FileReader and BufferedReader and then start checking :
outer loop -->while readLine is not null
if line matches //d+ --> read value of number and put it into count
from 0 to count do what you want to do // inner loop

Instead of reading into a separate scanner, you can read to end of line, and use String.split, like this:
while (scanner.hasNextInt()) {
int count = scanner.nextInt();
for (int i = 0 ; i != count ; i++) {
if (!scanner.hasNext()) throw new IllegalStateException("expected a name");
String name = scanner.next();
List<Integer> numbers = new ArrayList<Integer>();
for (String numStr : scanner.readLine().split(" ")) {
numbers.add(Integer.parseInt(numStr));
}
... // Do something with name and numbers
}
}
This approach avoids the need to detect the difference between the last int on a line vs. the first integer on next line by calling readLine() after reading a name, i.e. in the middle of reading a line.

File file = new File("records.txt");
BufferedReader reader = new BufferedReader(new FileReader(file));
String line = null;
/* Read file one line at a time */
while((line = reader.readLine()) != null){
int noOfRecords = Integer.parseInt(line);
/* read the next n lines in a loop */
while(noOfRecords != 0){
line = reader.readLine();
String[] tokens = line.split(" ");
noOfRecords--;
// do what you need to do with names and numbers
}
}
Here we're reading one line at a time, so the first time we read a line it will be an int (call it as n), from there read the next n lines in some inner loop. Once it's done with this inner loop it will come outside and the next time you read a line it's definitely another int or EOF. That way you don't have to deal with integer parsing exceptions and we'll read all the lines only once :)

counting the number of lines in a text file (java)

Below is how i count the number of lines in a text file. Just wondering is there any other methods of doing this?
while(inputFile.hasNext()) {
a++;
inputFile.nextLine();
}
inputFile.close();
I'm trying to input data into an array, i don't want to read the text file twice.
any help/suggestions is appreciated.
thanks

If you are using java 7 or higher version you can directly read all the lines to a List using readAllLines method. That would be easy
readAllLines
List<String> lines = Files.readAllLines(Paths.get(fileName), Charset.defaultCharset());
Then the size of the list will return you number of lines in the file
int noOfLines = lines.size();

If you are using Java 8 you can use streams :
long count = Files.lines(Paths.get(filename)).count();
This will have good performances and is really expressive.
The downside (compared to Thusitha Thilina Dayaratn answer) is that you only have the line count.
If you also want to have the lines in a List, you can do (still using Java 8 streams) :
// First, read the lines
List<String> lines = Files.lines(Paths.get(filename)).collect(Collectors.toList());
// Then get the line count
long count = lines.size();

If you just want to add the data to an array, then I append the new values to an array. If the amount of data you are reading isn't large and you don't need to do it often that should be fine. I use something like this, as given in this answer: Reading a plain text file in Java
BufferedReader fileReader = new BufferedReader(new FileReader("path/to/file.txt"));
try {
StringBuilder sb = new StringBuilder();
String line = br.readLine();
while (line != null) {
sb.append(line);
sb.append(System.lineSeparator());
line = br.readLine();
}
String everything = sb.toString();
} finally {
br.close();
}
If you are reading in numbers, the strings can be converted to numbers, say for integers intValue = Integer.parseInt(text)

I do not have enough reputation to comment but #superbob answer is almost perfect, indeed you must ensure to pass Charset.defaultCharset() as 2nd parameter like :
Files.lines(file.toPath(), Charset.defaultCharset()).count()
That's because Files.lines used UTF-8 by default and then using as it is on non default UTF-8 system can produce java.nio.charset.MalformedInputException.

java String != null not working reading from bufferedReader

In android I am getting the String value from BufferedReader and it is null after reading from file.
intstring = br.readLine();
System.out.println(intstring);
if(intstring != null)
{
System.out.println("Inside if condition");
int istring = Integer.parseInt(intstring);
}
My output is
null
Inside if condition
NumberFormatException
Help me please

Your NumberFormatException is happening because your input isn't a number. Maybe it's a blank line, or maybe it has some non-numeric characters. In fact, your output suggests that it's actually the word "null".
You've got some options.
You could check that the string contains digits and no other characters before you parse it, for example by using a regular expression and a condition like if (intString.matches("\\d+")).
You could catch the NumberFormatException, and do something particular when it happens.
You could check whether your string is blank, if you knew that there weren't going to be any non-numeric characters in the input. For this option, you might write if (!intString.equals(""))).