Java encountering runtime errors while trying to read text file
I'm currently trying to write a Java assignment that is supposed to, in order;
However, I am repeatedly running into a runtime problem where I am getting this error message;
Exception in thread "main" java.util.NoSuchElementException at java.util.Scanner.throwFor(Scanner.java:862) at java.util.Scanner.next(Scanner.java:1371) at Lab2.main(Lab2.java:27)
This leads me to believe I am probably reading the text file wrong. However, no matter what I do I can't seem to get it to read correctly. It's supposed to read a first name, a last name, three separate components of an address (which it concatenates into one string), a city, a state, a zip code (as an integer), a phone number (as a string) and a dollar amount (as a double).
I believe that the problem might arise from the city names, as some of them have a space between them. I thought I had solved this by setting the delimiter of the Scanner that reads each individual string to a tab (which is what every other element is separated by) but this has either not worked (And is thus trying to turn state names into an integer via the Integer.parseInt() static method) or is not the problem. As I said, I am out of ideas and would be greatly appreciative towards anyone who could help me out here!
I will list the code below. First here is the main file;
public class Lab2
{
public static void main(String[] args) throws IOException
{ String FirstName, LastName, Address1, Address2, Address3, AddressFull, City, State, Phone, ZipString, DonString, line = "blank";
int Zip;
double Donation;
Scanner fileScan = new Scanner(new File("Lab2.txt")), lineScan = new Scanner(line);
lineScan.useDelimiter("t");
PersonStats[] Donators = new PersonStats[25];
for (int i = 0; i < Donators.length; i++)
{ line = fileScan.nextLine();
FirstName = lineScan.next();
LastName = lineScan.next();
Address1 = lineScan.next();
Address2 = lineScan.next();
Address3 = lineScan.next();
AddressFull = Address1 + " " + Address2 + " " + Address3;
City = lineScan.next();
State = lineScan.next();
ZipString = lineScan.next();
Zip = Integer.parseInt(ZipString);
Phone = lineScan.next();
DonString = lineScan.next();
Donation = Double.parseDouble(DonString);
Donators[i] = new PersonStats(FirstName, LastName, AddressFull, City, State, Zip, Phone, Donation);
Donators[i].PrintOut();
}
}
}
Next, the class file I've written up for the assignment;
public class PersonStats
{ private String FirstName, LastName, Address, City, State, Phone;
private int Zip;
private double Donation;
public PersonStats(String first, String last, String area, String town, String feifdom, int postcode, String telegraph, double given)
{ FirstName = first;
LastName = last;
Address = area;
City = town;
State = feifdom;
Zip = postcode;
Phone = telegraph;
Donation = given;
}
public void PrintOut()
{ System.out.println(FirstName + " " + LastName);
System.out.println(Address);
System.out.println(City + ", " + State + " " + Zip + "n");
System.out.println(Phone + " " + Donation);
}
}
And then finally the text file the program is supposed to be reading from (Might be a little bit difficult to read, just remember each space except for the ones in city names is actually a tab);
Rick James 8276 Carlos Ave Las Vegas NV 87126 5553451567 23.95
John Gibson 9127 Oak Dr Corvallis OR 97330 5552812313 156.78
Ron Wills 1155 Ivy Pl Atlantic Ga 37339 5552123145 189.56
Rita Jones 1259 Chase Ave Las Vegas NV 87126 5554445671 2145.60
Jason Knight 7154 Pine Dr Gresjam OR 97380 5558124545 3157.44
Clara Swanson 1944 Main Pl Springfield OR 97339 5552123144 212.99
Robert Peck 1866 First Ave Las Vegas NV 87126 5553455425 250.00
Dora Garcia 2179 Fir Dr Corvallis OR 97330 5552812919 350.00
Peter Keck 1465 Circle Pl Gold Beach OR 97339 5552123256 2150.00
Stuart Smith 2387 Sweek Ave Las Vegas NV 87126 5553455489 650.99
Tyler Wild 1313 Spooky Ln Corvallis OR 97330 5552813213 587.45
Laretta Peters 2224 Chase Pl Monmouth OR 97361 5552124465 123.45
Kristi Emry 3465 Cerrito Ave Las Vegas NV 87126 5553455567 3212.65
Kelli Gard 1894 Elm Dr Corvallis OR 97330 5552816678 51.00
Jacob Andrews 8159 Rose Ct Mill City OR 97322 5552127879 64.00
Ryan Perkins 7546 Prince Ave Las Vegas NV 87126 5553451989 13.00
Joshua Gilbert 9278 Monroe Dr Corvallis OR 97330 5552832656 95.00
Miles Crain 4578 Chester Dr Corvallis OR 97331 5552345678 1544.00
Butch Cassidy 5498 Sutton Pl Gresham OR 97380 5416565797 1798.56
Perry Winkle 8185 Shaver Ave Las Vegas NV 87126 5553812346 195.66
Loni Day 4598 Holmen Dr Corvallis OR 97330 5555289741 1878.50
Nikita Benson 1787 Grant Pl Portland OR 97321 5553569898 1500.00
Rusty Krouger 8829 Simeon Ave Las Vegas NV 87126 5555677847 2100.00
Wally Wallace 2898 Wilson Blvd Jackson Center OH 23466 5552222222 2222.22
Joe Jones 1212 Water St Millersburg OR 97366 5555555555 55.55
Again, thanks in advance if there's anyone out there who can help me with this, your advice might save a life!... or at least the score of this lab :S
Okay, here it is
import java.io.IOException;
import java.io.*;
import java.util.Scanner;
public class Lab2
{
public static void main(String[] args) throws IOException
{ String FirstName, LastName, Address1, Address2, Address3, AddressFull, City, State, Phone, ZipString, DonString, line = "blank";
int Zip;
double Donation;
Scanner fileScan = new Scanner(new File("F:/test.txt")).useDelimiter("n");
PersonStats[] Donators = new PersonStats[5];
String tempVal="";
int i = 0;
while(fileScan.hasNext())
{
tempVal = fileScan.next(); //Storing person records one at a time in the string line by line
String tempArr[] = tempVal.split("t"); //Splitting each person record string by tab and storing it in a String array
FirstName = tempArr[0];
LastName = tempArr[1];
Address1 = tempArr[2];
Address2 = tempArr[3];
Address3 = tempArr[4];
AddressFull = Address1 + " " + Address2 + " " + Address3;
City = tempArr[5];
State = tempArr[6];
ZipString = tempArr[7];
Zip = Integer.parseInt(ZipString);
Phone = tempArr[8];
DonString = tempArr[9];
Donation = Double.parseDouble(DonString);
Donators[i] = new PersonStats(FirstName, LastName, AddressFull, City, State, Zip, Phone, Donation);
Donators[i].PrintOut();
i++;
}
}
}
First of all, I would like to point out that your variable names should start with lower case. I did not edit them in the code since they were used in many places. Make an habit to declare String firstName instead of String FirstName
To the code, in your code you had used a "t" delimter which I replaced with "n" since in the text file each line holds entire Person details. You could have used "t" if the donation of the first person and first name of the second person were separated by the same, but they are separated by "n"
So now Scanner fileScan will read the file line by line which I will store in String tempVal and while(fileScan.hasNext()) assures that the Scanner will keep reading only as long as there are lines to be read.
Now, every line has different information separated by "t" . So I used tempVal.split("t") to separate them. Also, used a counter int i and removed the for loop. I guess rest of the code is pretty basic and not much different from yours.
**EDIT****
Here is the output
Rick James
8276 Carlos Ave
Las Vegas, NV 87126
5553451567 23.95
John Gibson
9127 Oak Dr
Corvallis, OR 97330
5552812313 156.78
Ron Wills
1155 Ivy Pl
Atlantic, Ga 37339
5552123145 189.56
Rita Jones
1259 Chase Ave
Las Vegas, NV 87126
5554445671 2145.6
Jason Knight
7154 Pine Dr
Gresjam, OR 97380
5558124545 3157.44
And here is the sample text.file that I used.
Rick James 8276 Carlos Ave Las Vegas NV 87126 5553451567 23.95
John Gibson 9127 Oak Dr Corvallis OR 97330 5552812313 156.78
Ron Wills 1155 Ivy Pl Atlantic Ga 37339 5552123145 189.56
Rita Jones 1259 Chase Ave Las Vegas NV 87126 5554445671 2145.60
Jason Knight 7154 Pine Dr Gresjam OR 97380 5558124545 3157.44
here is a tip: When using Scanner use the hasNextXXX method before invoking next methods to check if elements exists
https://docs.oracle.com/javase/7/docs/api/java/util/Scanner.html
No Such Element Exception?
Scanner fileScan = new Scanner(new File("Lab2.txt"));
//PersonStats[] Donators = new PersonStats[25];
while(fileScan.hasNext()) {
line = fileScan.nextLine();
String parts[] = line.split("t");
if(parts.length == 10) {
FirstName = parts[0];
...
}
There are some problems in addion. First: String ist immutable. So your lineScanner will created with an empty String. If you later change this string, nothing appens for this scanner, because you create a new string with this step.
Second you have to check for an next element. (see my while loop)
To parse your data it is easyer to split the string in parts and use this to fill your Class. But if you want to use the Scanner class, you have to create on instance per line in your file.(in the while loop)
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