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Why am I getting NoSuchElement Exception?

I'm getting the following errors and having troubles with fixing it. Any help is appreciated! Before anyone jumps saying that my code needs to look "cleaner" please know I'm brand new to this and still learning.
When running my Game.java it's giving me this...
Exception in thread "main" java.util.NoSuchElementException: No line found
at java.base/java.util.Scanner.nextLine(Scanner.java:1651)
at ItemGenerator.textFileReaderSpecialItems(ItemGenerator.java:71)
at ItemGenerator.<init>(ItemGenerator.java:22)
at Game.<init>(Game.java:9)
at Game.main(Game.java:16)
This is the code around these lines
ItemGenerator.java
58 public void textFileReaderSpecialItems(String x) {
59
60 try {
61
62 Scanner fileSc = new Scanner(new File(x));
63
64 while(fileSc.hasNext() && fileSc != null) {
65
66 String s1;
67 String s2;
68 String s3;
69
70 s1 = fileSc.nextLine();
71 s2 = fileSc.nextLine();
72 s3 = fileSc.nextLine();
73
74 itemsList.add(new Items(s1, s2, s3));
75 }
76
77 fileSc.close();
78
79 } catch (FileNotFoundException e) {
80
81 System.out.println("\nError: " + e + "\nProgram exiting...\n");
82 System.exit(0);
83
84 }
85
87 }
3 public Game() {
4
5 LocationGenerator newLocationGenerator = new LocationGenerator("Locations.txt");
6 MainCharacterGenerator newMainCharacter = new MainCharacterGenerator("MainCharacter.txt");
7 CharacterGenerator newCharacter = new CharacterGenerator("Characters.txt", "Jabberwocky.txt");
8 ItemGenerator newItem = new ItemGenerator("Items.txt", "SpecialItems.txt");
9 newLocationGenerator.startLocation();
10
11 }
12
13 public static void main(String[] args) {
14
15 Game game = new Game();
16
17 }
Any help would be appreciated! Learning curve for me!
Labeled all my information

The following will ensure your list is filled when the input file is valid:
public void textFileReaderSpecialItems(String x) {
try {
Scanner fileSc = new Scanner(new File(x));
int lineCount = 0;
List<String> lineBuffer = new ArrayList<>();
while (fileSc.hasNextLine()) {
lineBuffer.add(fileSc.nextLine());
lineCount++;
if (lineBuffer.size() % 3 == 0) {
itemsList.add(new Items(lineBuffer.get(0), lineBuffer.get(1), lineBuffer.get(2)));
lineBuffer.clear();
}
}
System.out.println(itemsList);
fileSc.close();
} catch (FileNotFoundException e) {
System.err.println("\nError: " + e + "\nProgram exiting...\n");
System.exit(1);
}
}
Note that method names should be verb-based, not noun-based. So, something like fillSpecialItems. Also, only return an exit code of zero on success. Use System.err for errors. Later, you will use System.err.printf maybe. Note the format character for a line separator is "%n". What you used ("\n") is OS-specific. Really, if you're not using logging (which you should in real-world, professional apps) you should always use e.printStackTrace() for exceptions - you want the maximum info possible.

JAVA Array Index Problems

I am not experienced wit Arrays and I am getting this error in the debug console:
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: Index 1 out of bounds for length 1
at com.company.SortTextFile.main(SortTextFile.java:28)
I've been looking in internet for how other people handle this included here in StackOverflow but I can't seem to understand why is it happening. I am trying to have this program get the input from a text file of multiple columns with 20 lines like this:
Eduardo 15 3.9 30000
And then using collection.sort to sort it using its id.
I am aware the arrays are 0-index however I don't know if I would need to specify the array size.
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import static java.lang.Double.*;
public class SortTextFile {
public static void main(String[] args) throws IOException {
// Creating BufferedReader object to read the input text file
BufferedReader reader = new BufferedReader(new FileReader(
"C:\\Users\\miche\\OneDrive\\Documentos\\University\\Algorithms\\Project\\StudentData.txt"));
// Creating ArrayList to hold Student objects
var studentRecords = new ArrayList<Student>();
// Reading Student records one by one
String currentLine = reader.readLine();
while (currentLine != null) {
String[] studentDetail = currentLine.split("\\s+");
String name = studentDetail[0];
int age = Integer.valueOf(studentDetail[1]);
double GPA = valueOf(studentDetail[2]);
int id = Integer.valueOf(studentDetail[3]);
// Creating Student object for every student record and adding it to
// ArrayList
studentRecords.add(new Student(name, age, GPA, id));
currentLine = reader.readLine();
}
// Sorting ArrayList studentRecords based on marks
Collections.sort(studentRecords, new idCompare());
// Creating BufferedWriter object to write into output text file
BufferedWriter writer = new BufferedWriter(new FileWriter(
"C:\\C:\\Users\\miche\\OneDrive\\Documentos\\University\\Algorithms\\Project\\output.txt"));
// Writing every studentRecords into output text file
for (Student student : studentRecords) {
writer.write(student.name);
writer.write(" " + student.age);
writer.write(" " + student.GPA);
writer.write(" " + student.id);
writer.newLine();
}
// Closing the resources
reader.close();
writer.close();
}
}
I made a Student class to compare the IDs.
public class Student extends SortTextFile {
String name;
int id;
int age;
double GPA;
public Student(String name, int id, double age, double GPA) {
this.name = name;
this.id = id;
this.age = (int) age;
this.GPA = GPA;
}
}
//idCompare Class to compare the marks
class idCompare implements Comparator<Student> {
#Override
public int compare(Student s1, Student s2) {
return s2.id - s1.id;}
}
Edit 1:
The text file just follows a format of Name/Age/GPA/ID:
Chipaldo 25 3.5 29000
Eduardo 15 3.9 30000
Ricardo 23 3.8 18000
Anthony 24 3.9 19000
Lombardo 29 2.0 22000
Romina 28 2.1 23000
Alex 25 3.1 13000
Sofia 21 2.2 24000
Vexler 24 2.2 25000
Albert 19 3.2 14000
John 24 3.0 15000
Melchor 14 2.9 16000
Bernardo 21 4.0 17000
Diego 19 2.1 26000
Miguelangel 25 2.0 27000
Edit 3: I managed to printout the Output in a new file. It sorted it based on age and not ID for some reason. Thank you for your help. I am going to try implement and Binary Insertion Sort to this program instead of doing Collection.sort Thanks.
If possible please be as detailed as possible with any suggestion. English is not my main language & I am slow at this. Thank you in advance

The message simply means that you have an array that only has 1 element in it and you are trying to access array element 2. This is one of those weird things in computer science (and Java as a language) because we start counting from zero rather than one, i.e. the first element in an array is indexed as studentDetail[0] and the second as studentDetail[1]. This is why you see the rather confusing "Index 1 out of bounds for length 1". The array being returned by currentLine.split(" ") only contains one string, not four, as you are expecting. You need to debug the code to find out why this is happening (from what you've provided this is not possible for someone else to answer).

your array seems to only have one entry. check if there is a problem with your string.split(" ")?

Use currentLine.split("\\s+"); This means that there may be one or more spaces or tabs or newlines between fields.
What you did will work correctly if and only if the fields are separated by one single space.
For debugging purpose print the length of the array using System.out.println(studentDetail.length);

Try This. Your code you did not closed writer thats why nothing is to in the output file.
public static void main(String[] args) throws IOException {
//Creating BufferedReader object to read the input text file
BufferedReader reader = new BufferedReader(new FileReader("E:\\Projects\\JavaBasics\\src\\data.txt"));
//Creating ArrayList to hold Student objects
var studentRecords = new ArrayList<Student>();
//Reading Student records one by one
String currentLine = null;
while ((currentLine = reader.readLine()) != null) {
if (!currentLine.isEmpty()) {
System.out.println(currentLine);
String[] studentDetail = currentLine.split(" ");
String name = studentDetail[0];
int age = Integer.valueOf(studentDetail[1]);
double GPA = Double.valueOf(studentDetail[2]);
int id = Integer.valueOf(studentDetail[3]);
studentRecords.add(new Student(name, age, GPA, id));
}
}
//Sorting ArrayList studentRecords based on marks
Collections.sort(studentRecords, new IdCompare());
//Creating BufferedWriter object to write into output text file
BufferedWriter writer = null;
try {
writer = new BufferedWriter(new FileWriter(new File("E:\\Projects\\JavaBasics\\src\\dataout.txt")));
//Writing every studentRecords into output text file
for (Student student : studentRecords) {
System.out.println("Sorted :: " + student.name);
writer.write(student.name);
writer.write(" " + student.age);
writer.write(" " + student.GPA);
writer.write(" " + student.id);
writer.newLine();
}
} finally {
writer.close();
}
}

Finding closest number from two arraylists

Recently one of my data servers went down and a large number of video files are damaged (over 15,000 files, or more than 60TB). I wrote a script to check all files and put results in a very big log.txt file (almost 8GB).
I wrote code to find all lines starting with "Input #0" and lines which contain "damaged", then added their line numbers to ArrayList's. Next, I need to compare those two ArrayLists and find the closest line number in list2 to the number in list1 so I can get back file names from the log file.
For example:
if list1 contains numbers {1, 5, 45, 55, 100, 2000... etc}
and list2 contains numbers {50, 51, 53, 2010... etc} the result should be {45, 2000... etc}
This is my current code:
import java.io.*;
import java.util.*;
public class Log {
public static void main(String [] args) throws IOException{
ArrayList<Integer> list1 = new ArrayList<Integer>();
ArrayList<Integer> list2 = new ArrayList<Integer>();
File file = new File("C:\\log.txt");
try {
Scanner scanner = new Scanner(file);
Scanner scanner2 = new Scanner(file);
int lineNum = 0;
int lineNum2 = 0;
while (scanner.hasNextLine()){
String line = scanner.nextLine();
String line2 = scanner.nextLine();
lineNum++;
lineNum2++;
if((line.startsWith("Input #0"))) {
list1.add(lineNum);
}
if((line2.contains("damaged"))) {
list2.add(lineNum2);
}
}
This is what I'm getting from the code above:
list1 [5, 262, 304, 488, 523, 1189, 1796, 2503, 2722, 4052, 4201, 4230, 4298, 4312, 4559, 4887, 4903, 5067....]
list2 [1838, 1841, 1842, 1844, 1851, 1861, 1865, 1866, 1868, 1875, 1878, 1879, 1880, 1881, 1886, 1887, 1891....]
Some log data:
Input #0, mpegvideo, from '/cinegy/cinegy/VIDEO/BSF/BLOK 3 - 14. NOVHighb668ca7d201411141051110636.m2v':
.
.
.
.
.
.
Data with damage:
Input #0, mpegvideo, from '/cinegy/cinegy/VIDEO/BSF/BLOK 3 - 14. NOVHighb668ca7d201411141051110636.m2v':
.
.
.
.
.
[error 0x090010] file damaged at 16 09
[error 0x090010] file damaged at 19 15
The log for each individual file does not contain any pattern except for the first 5-6 lines or so. Both damaged and non-damaged files contain info written in 20 to 100+ lines.
So, from these numbers the first result should be number 1796.
I'm pretty much a novice in Java and I need help.

Here's a small code that will do the work, but I don't know if you want redundant values in the result, so I saved them in a list and in a set, choose the one you prefer:
public static void main(String[] args) {
int[] list1 = {5, 262, 304, 488, 523, 1189, 1796, 2503, 2722, 4052, 4201, 4230, 4298, 4312, 4559};
int[] list2 = {1838, 1841, 1842, 1844, 1851, 1861, 1865, 1866, 1868, 1875, 1878, 1879, 1880, 1881};
ArrayList<Integer> resultList = new ArrayList<Integer>();
Set<Integer> resultSet = new HashSet<Integer>();
int j = 0;
for(int i = 0; i < list2.length; i++){
for(; j < list1.length; j++){
if(list1[j] > list2[i])
break;
}
resultList.add(list1[j-1]);
resultSet.add(list1[j-1]);
}
System.out.println(resultList);
System.out.println(resultSet);
}
Output:
[1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796, 1796]
[1796]

You defined two scanners (seems unnecessary) but you are only using one of them and calling nextline() twice on it. It looks like that is not intended and as a consequence the results you are getting are erroneous. It would be very helpful if you could post a sample excerpt from your logfile (you can filter the sensitive data) so that we can determine what the best approach is for this.
I think you should scrap your current approach because it does not seem like an efficient way to solve your problem of needing to find filenames of damaged files.
Depending on how your data looks, you can use regular expressions and possibly even extract the filenames directly into a Set.
Edit: Added some rough code that should do the job for you if you are indeed correct that each file starts with "Input #0". As long as there is a pattern in the log data for each file, then you should always be able to extract the data you need directly instead of going through the mess of matching entries from two separate arraylists.
public static void main(String [] args) throws FileNotFoundException{
Set<String> damagedFiles = new LinkedHashSet<String>();
File file = new File("C:\\log.txt");
Scanner scanner = new Scanner(file);
String filename = null;
try {
int lineNum = 0;
while (scanner.hasNextLine()){
String line = scanner.nextLine();
if(line.startsWith("Input #0")){
/*if desired, can use a regex lookahead to get only the path and filename
instead of the entire Input #0 line */
filename = line;
}
if(line.contains("damaged")){
if (filename != null){
damagedFiles.add(filename);
}
}
}
} finally {
scanner.close();
for (String s : damagedFiles){
System.out.println(s);
}
}
}
This is the result I got when running this code on a sample log file where I named the damaged files dmg#.m2v
Input #0, mpegvideo, from '/cinegy/cinegy/VIDEO/BSF/BLOK 3 - 14. dmg1.m2v':
Input #0, mpegvideo, from '/cinegy/cinegy/VIDEO/BSF/BLOK 3 - 14. dmg2.m2v':
Input #0, mpegvideo, from '/cinegy/cinegy/VIDEO/BSF/BLOK 3 - 14. dmg3.m2v':
Input #0, mpegvideo, from '/cinegy/cinegy/VIDEO/BSF/BLOK 3 - 14. dmg4.m2v':

Reading txt file, then re organizing it to an array

So basically what I need to do is:
Read a text file like this:
[Student ID], [Student Name], Asg 1, 10, Asg 2, 10, Midterm, 40, Final, 40
01234567, Timture Choi, 99.5, 97, 100.0, 99.0
02345678, Elaine Tam, 89.5, 88.5, 99.0, 100
and present it like this (with calculations of rank and average):
ID Name Asg 1 Asg 2 Midterm Final Overall Rank
01234567 Timture Choi 99.5 97.0 100.0 99.0 99.3 1
02345678
Elaine Tam 89.5 88.5 99.0 100.0 97.4 2
Average: 94.5 92.75 99.5 99.5 98.3
Using printf() function
now this is what I have done so far:
import java.io.*;
import java.util.Scanner;
class AssignmentGrades {
public static void main(String args[]) throws Exception {
Scanner filename = new Scanner(System.in);
String fn = filename.nextLine(); //scannig the file name
System.out.println("Enter your name of file : ");
FileReader fr = new FileReader(fn+".txt");
BufferedReader br = new BufferedReader (fr);
String list;
while((list = br.readLine()) !=null) {
System.out.println(list);
}
fr.close();
}
}
So I can ask the user for the name of the file, then read it and print.
Now.. I'm stuck. I think I need to probably put it in to array and split?
String firstrow = br.readLine();
String[] firstrow = firstrow.split(", ");
something like that?.. ugh ive been stuck here for more than an hour
I really need help!! I appreciate your attention!! ( I started to learn java this week)

There are two ways for splitting the input line just read from the file
Using String object's split() method which would return an array. Read more about the split here.
StringTokenizer Class - This class can be used to divide the input string into separate tokens based on a set of delimeter. Here is a good tutorial to get started.
You should be able to get more examples using google :)
In case you want to parse integers from String. Check this.

Here I store the columns as an array of Strings and I store the record set as an ArrayList of String arrays. In the while loop if the column set is not initialized yet (first iteration) I initialize it with the split. Otherwise I add the split to the ArrayList. Import java.util.ArrayList.
String[] columns = null;
ArrayList<String[]> values = new ArrayList<String[]>();
String list;
while((list = br.readLine()) !=null) {
if (columns != null) {
columns = list.split(", ");
} else {
values.add(list.split(", "));
}
}
fr.close();

TSV file into 2d array - java

I have a tsv txt file containing data in 3 rows.
It looks like:
HG sn FA
PC 2 16:0
PI 1 18:0
PS 3 20:0
PE 2 24:0
26:0
16:1
18:2
I want to read this file into a 2 dimensional array in java.
But i get an error all the time, no matter what i try.
File file = new File("table.txt");
Scanner scanner = new Scanner(file);
final int maxLines = 100;
String[][] resultArray = new String[maxLines][];
int linesCounter = 0;
while (scanner.hasNextLine() && linesCounter < maxLines) {
resultArray[linesCounter] = scanner.nextLine().split("\t");
linesCounter++;
}
System.out.print(resultArray[1][1]);
I keep getting this error
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 1
at exercise.exercise2.main(exercise2.java:31)
Line 31 is
System.out.print(resultArray[1][1]);
I cannot find any reasons why this error keeps emerging

In your case I would use Java 7 Files.readAllLines.
Something like:
String[][] resultArray;
List<String> lines = Files.readAllLines(Paths.get("table.txt"), StandardCharsets.UTF_8);
//lines.removeAll(Arrays.asList("", null)); // <- remove empty lines
resultArray = new String[lines.size()][];
for(int i =0; i<lines.size(); i++){
resultArray[i] = lines.get(i).split("\t"); //tab-separated
}
Output:
[[HG, sn FA ], [PC, 2, 16:0], [PI, 1, 18:0], [PS, 3, 20:0], [PE, 2, 24:0], [, , 26:0], [, , 16:1], [, , 18:2]]
And this is the file (press edit and grab the content, it should be tab separated):
HG sn FA
PC 2 16:0
PI 1 18:0
PS 3 20:0
PE 2 24:0
26:0
16:1
18:2
[EDIT]
To get 16:1:
System.out.println(root[6][2]);