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Appending items from a txt file to an array

Hey I just started learning how to code. I am using netbeans and I want to transfer some data from a txt.file into an array in java. This might be a really simple fix but i just cant see whats wrong
This is the data in the txt.file:
58_hello_sad_happy
685_dhejdho_sahdfihsf_hasfi
544654_fhokdf_dasfjisod_fhdihds
This is the code I am using however smthg is wrong with the last line of code:
int points = 0;
String name = "";
String a = "";
String b = "";
public void ReadFiles() throws FileNotFoundException{
try (Scanner input = new Scanner(new File("questions.txt"))) {
String data;
while(input.hasNextLine()){
data = input.nextLine();
String[] Questions = data.split("_");
points = Integer.parseInt(Questions[0]);
name= Questions[1];
a = Questions[2];
b = Questions[3];
}
System.out.println(Arrays.toString(Questions));
}
}
This is the error I am getting:
error: cannot find symbol
System.out.println(Arrays.toString(Questions));
Thx soooo much guys.

You can also use the below code if you just want to print the data:
Files.readAllLines(Paths.get("questions.txt")).forEach(line -> {
System.out.println(Arrays.toString(line.split("_")));
});
Output is :
[58, hello, sad, happy]
[685, dhejdho, sahdfihsf, hasfi]
[544654, fhokdf, dasfjisod, fhdihds]
The correct version of your code should be like the below (you must access the variable Question in the declared scope by moving println into end of while loop) :
// definitions...
public void ReadFiles() throws FileNotFoundException{
try (Scanner input = new Scanner(new File("questions.txt"))) {
String data;
while(input.hasNextLine()){
data = input.nextLine();
String[] Questions = data.split("_");
points = Integer.parseInt(Questions[0]);
name= Questions[1];
a = Questions[2];
b = Questions[3];
System.out.println(Arrays.toString(Questions));
}
}
}

Object needs to created from the file and placed into an array

I am trying to create an object for each line of text and as each object is created, place it into an array. I'm struggling to place it into an array. This is my code:
File inFile = new File("shareholders.txt");
Scanner inputFile = new Scanner(inFile);
String str;
Shareholder shareholder = new Shareholder();
while (inputFile.hasNext()) {
str = inputFile.nextLine();
String tokens[] = str.split(",");
shareholder.setID(tokens[0]);
shareholder.setName(tokens[1]);
shareholder.setAddress(tokens[2]);
shareholder.setPortfolioID(tokens[3]);
}

If you have a fixed number of shareholders, you can do this -
File inFile = new File("shareholders.txt");
Scanner inputFile = new Scanner(inFile);
String str;
int i=0;
Shareholder[] shareholder = new Shareholder[n];
while (inputFile.hasNext()) {
str = inputFile.nextLine();
String tokens[] = str.split(",");
shareholder[i++] = new Shareholder(tokens[0],tokens[1],tokens[2],tokens[3]);
}
Or if dont know the number of shareholders, then you can use list -
File inFile = new File("shareholders.txt");
Scanner inputFile = new Scanner(inFile);
String str;
List<Shareholder> list = new ArrayList<>();
while (inputFile.hasNext()) {
Shareholder shareholder = new Shareholder();
str = inputFile.nextLine();
String tokens[] = str.split(",");
list.add(new Shareholder(tokens[0],tokens[1],tokens[2],tokens[3]));
}

I think a list of shareholder objects might make the most sense here:
File inFile = new File("shareholders.txt");
Scanner inputFile = new Scanner(inFile);
String str;
List<Shareholder> list = new ArrayList<>();
while (inputFile.hasNext()) {
Shareholder shareholder = new Shareholder();
str = inputFile.nextLine();
String tokens[] = str.split(",");
shareholder.setID(tokens[0]);
shareholder.setName(tokens[1]);
shareholder.setAddress(tokens[2]);
shareholder.setPortfolioID(tokens[3]);
list.add(shareholder);
}
The reason a list makes sense here is because you might not know how many shareholders are present in the input file. Hence, an array might not work so well in this case (and even if the number of shareholders were fixed it could change at some later date).

Before reading the file, you can not know how many lines the file has.
The information about the number of lines is important to initialize your array with that specific size or otherwise you would need to extend your array multiple times by creating a new, bigger one. Which is bad practice and bad performance.
But instead of working with an array itself, use an arraylist for easier usage and just return a simple array, which can be received from the arraylist you worked with.
My suggestion as a solution for this issue is the following. Please note that the following code is not 100% complete and will not run in it's state. It is your job to complete it and make it run.
public void readFileIntoArray(String filename, Shareholder[] targetArray)
{
File sourceFile = new File(filename);
// Read in the file to determine the number of lines (int numberOfLines)
ArrayList<Shareholder> lines = new ArrayList<>(numberOfLines);
Shareholder sh;
while(file.hasNext())
{
sh = new Shareholder();
//Parse data into Shareholderobject
lines.add(sh);
}
return lines.toArray();
}

Identifying each word in a file

Importing a large list of words and I need to create code that will recognize each word in the file. I am using a delimiter to recognize the separation from each word but I am receiving a suppressed error stating that the value of linenumber and delimiter are not used. What do I need to do to get the program to read this file and to separate each word within that file?
public class ASCIIPrime {
public final static String LOC = "C:\\english1.txt";
#SuppressWarnings("null")
public static void main(String[] args) throws IOException {
//import list of words
#SuppressWarnings("resource")
BufferedReader File = new BufferedReader(new FileReader(LOC));
//Create a temporary ArrayList to store data
ArrayList<String> temp = new ArrayList<String>();
//Find number of lines in txt file
String line;
while ((line = File.readLine()) != null)
{
temp.add(line);
}
//Identify each word in file
int lineNumber = 0;
lineNumber++;
String delimiter = "\t";
//assess each character in the word to determine the ascii value
int total = 0;
for (int i=0; i < ((String) line).length(); i++)
{
char c = ((String) line).charAt(i);
total += c;
}
System.out.println ("The total value of " + line + " is " + total);
}
}

This smells like homework, but alright.
Importing a large list of words and I need to create code that will recognize each word in the file. What do I need to do to get the program to read this file and to separate each word within that file?
You need to...
Read the file
Separate the words from what you've read in
... I don't know what you want to do with them after that. I'll just dump them into a big list.
The contents of my main method would be...
BufferedReader File = new BufferedReader(new FileReader(LOC));//LOC is defined as class variable
//Create an ArrayList to store the words
List<String> words = new ArrayList<String>();
String line;
String delimiter = "\t";
while ((line = File.readLine()) != null)//read the file
{
String[] wordsInLine = line.split(delimiter);//separate the words
//delimiter could be a regex here, gotta watch out for that
for(int i=0, isize = wordsInLine.length(); i < isize; i++){
words.add(wordsInLine[i]);//put them in a list
}
}

You can use the split method of the String class
String[] split(String regex)
This will return an array of strings that you can handle directly of transform in to any other collection you might need.
I suggest also to remove the suppresswarning unless you are sure what you are doing. In most cases is better to remove the cause of the warning than supress the warning.

I used this great tutorial from thenewboston when I started off reading files: https://www.youtube.com/watch?v=3RNYUKxAgmw
This video seems perfect for you. It covers how to save file words of data. And just add the string data to the ArrayList. Here's what your code should look like:
import java.io.*;
import java.util.*;
public class ReadFile {
static Scanner x;
static ArrayList<String> temp = new ArrayList<String>();
public static void main(String args[]){
openFile();
readFile();
closeFile();
}
public static void openFile(){
try(
x = new Scanner(new File("yourtextfile.txt");
}catch(Exception e){
System.out.println(e);
}
}
public static void readFile(){
while(x.hasNext()){
temp.add(x.next());
}
}
public void closeFile(){
x.close();
}
}
One thing that is nice with using the java util scanner is that is automatically skips the spaces between words making it easy to use and identify words.

How to read a txt file to an ArrayList of unknown size

How do I read from a txt file with lines of unknown size? For example:
Family1,john,mark,ken,liam
Family2,jo,niamh,liam,adam,apple,joe
Each line has a different number of names. I am able to read in when using object type like
family(parts[0], parts[1], parts[2])
but thats if I know the amout that will be in each. how do I read it in without knowing how many will be in each?
FileReader fr = new FileReader("fam.txt");
BufferedReader br = new BufferedReader(fr);
String fileLines;
String[] parts;
while(br.ready())
{
fileLines = br.readLine();
parts = fileLines.split(",");
.
.

You can use varargs for your family() method to accept the array: family(String ... parts) or just use family(String[] parts).
Personally, I would create a separate class Family and not pollute it with implementation detail about the file format (i.e. that the first item on each line is the family name):
public class Family {
private final List<String> members = new ArrayList<>();
private final String familyName;
public Family(String familyName, Collection<String> members) {
this.familyName = familyName;
this.members.addAll(members);
}
}
Then your loop can be like this:
List<Family> families = new ArrayList<>();
String line;
while ((line = br.readLine()) != null) {
List<String> parts = Arrays.asList(line.split(","));
String familyName = parts.remove(0);
families.add(new Family(familyName, parts));
}

ArrayList<E>: Resizable-array implementation of the List interface. Implements all optional list operations, and permits all elements, including null, provides methods to manipulate the size of the array that is used internally to store the list.
Each ArrayList instance has a capacity: size of the array used to store the elements in the list. It is always at least as large as the list size. As elements are added to an ArrayList, its capacity grows automatically. The details of the growth policy are not specified beyond the fact that adding an element has constant amortized time cost.
So just read your data and add to the array-list using ArrrayList.add(E e) method.

You're struggling since you try to load the data to an String[] which is in turn a plain array. You should use ArrayList that maintains an internal array and it increase its size dynamically.
FileReader fr = new FileReader("fam.txt");
BufferedReader br = new BufferedReader(fr);
String fileLines;
String[] parts;
List<List<String>> data = new ArrayList<>();
while(br.ready()) {
fileLines = br.readLine();
parts = fileLines.split(",");
data.add(Arrays.asList(parts));
//do what you want/need...
}
//do what you want/need...
A better approach would be parsing the data in String[] parts and build an object of some class that will contain the data for your specific case:
public void yourMethod() {
FileReader fr = new FileReader("fam.txt");
BufferedReader br = new BufferedReader(fr);
String fileLines;
String[] parts;
List<Family> familyList = new ArrayList<>();
while(br.ready()) {
fileLines = br.readLine();
parts = fileLines.split(",");
Family family = new Family(parts[0], parts[1], parts[2]);
familyList.add(family);
//do what you want/need...
}
//do what you want/need...
}

My personal preference is to use the Scanner class. You can review the functionality here. With the scanner you can parse the file a line at a time and store those values into a String.
Scanner scan = new Scanner(new File("fam.txt"));
List<String> families = new ArrayList<String>();
while(scan.hasNextLine()){
families.add(scan.nextLine());
}
Then you can do whatever you want with the families in the ArrayList

use a Scanner, that's much easier. You can put both in a while loop
Scanner sc = new Scanner(new File(myFile.txt));
while(sc.hasNextLine()) {
while(sc.hasNextString()) {
String str = sc.nextString();
}
}
This is a simplefied version and it will not work correctly, because you have to store some values in variables for Java to read them correctly. Read the documentation on the Java Scanner to find a more detailed explanation. The Scanner is much easier than what you have been doing

Read each line in a text file for strings, doubles, and ints an place them in different arrays

this is my first question here so I hope I'm doing this right. I have a programming project that needs to read each line of a tab delimited text file and extract a string, double values, and int values. I'm trying to place these into separate arrays so that I can use them as parameters. This is what I have so far(aside from my methods):
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.Scanner;
public class LoanDriver {
public static void main(String[] args)
{
String[] stringData = new String[9];
Scanner strings = null;
try
{
FileReader read = new FileReader("amounts.txt");//Read text file.
strings = new Scanner(read);
String skip = strings.nextLine();//Skip the first line by storing it in an uncalled variable
strings.useDelimiter("\t *");//Tab delimited
}
catch (FileNotFoundException error)
{}
while (strings.hasNext())
{
String readLine = strings.next();
stringData = readLine.split("\t");
}
}}
If I try to get the [0] value, it skips all the way to the bottom of the file and returns that value, so it works to some extent, but not from the top like it should. Also, I can't incorporate arrays into it because I always get an error that String[] and String is a type mismatch.

Instead of using delimiter, try reading the file line by line using Scanner.nextLine and split each new line you read using String.split ("\t" as argument).
try {
FileReader read = new FileReader("amounts.txt");//Read text file.
strings = new Scanner(read);
String skip = strings.nextLine();//Skip the first line by storing it in an uncalled variable
}
catch (FileNotFoundException error) { }
String line;
while ((line = strings.nextLine()) != null) {
String[] parts = line.split("\t");
//...
}

You are getting the last value in the file when you grab stringData[0] because you overwrite stringData each time you go through the while loop. So the last value is the only one present in the array at the end. Try this instead:
List<String> values = new ArrayList<String>();
while (strings.hasNext()) {
values.add(strings.next());
}
stringData = values.toArray(new String[values.size()]);