Error: NoSuchElementException - java.util.scanner

Question

This program accesses a text file with text elements separated by commas. The elements register in the variables I created. Except for the last one. The error then occurs. The program works fine with the default whitespace delimitor for the scanner class (the text file is adjusted accodingly) but fails when I use a comma as the delimitor. Could someone please supply some insight.
Text Data:
smith,john,10
stiles,pat,12
mason,emrick,12
Code:
public void openFile(String f)
{
try{
x = new Scanner(new File(f));
x.useDelimiter(",");
} catch(Exception e){
System.out.println("File could not be found please check filepath");
}
}
public boolean checkNameRoster()
{
openFile(file);
boolean b = false;
while(x.hasNext())
{
String lName = x.next().trim();
**String fName = x.next().trim();**
String grade = x.next().trim();
if(fName.equalsIgnoreCase(firstName) && lName.equalsIgnoreCase(lastName) && grade.equalsIgnoreCase(grade))
{
b = true;
}
}
closeFile();
return b;
}

Answer 1

The problem relies on the fact that you called x.useDelimiter(","); on your Scanner in function openFile().
Since your text data is:
smith,john,10
stiles,pat,12
mason,emrick,12
the Scanner sees it as:
"smith,john,10\nstiles,pat,12\nmason,emrick,12"
So what happens when you execute your code is:
1: x.hasNext() ? Yes
x.next().trim() => "smith"
x.next().trim() => "john"
x.next().trim() => "10\nstiles"
2: x.hasNext() ? Yes
x.next().trim() => "pat"
x.next().trim() => "12\nmason"
x.next().trim() => "emrick"
3: x.hasNext() ? Yes
x.next().trim() => "12"
x.next().trim() => Error!
To fix this you can either edit the file and change all the \n with ,, or use a first Scanner to get all the lines, and another one to get the tokens, as shown here:
public void openFile(String f)
{
try{
x = new Scanner(new File(f)); // Leave default delimiter
} catch(Exception e){
System.out.println("File could not be found please check filepath");
}
}
public boolean checkNameRoster()
{
openFile(file);
boolean b = false;
while(x.hasNextLine()) // For each line in your file
{
Scanner tk = new Scanner(x.nextLine()).useDelimiter(","); // Scan the current line
String lName = x.next().trim();
String fName = x.next().trim();
String grade = x.next().trim();
if (fName.equalsIgnoreCase(firstName) && lName.equalsIgnoreCase(lastName) && grade.equalsIgnoreCase(grade))
{
b = true;
}
}
closeFile();
return b;
}