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Read the data from the file and store it in two arrays

hello I am having trouble with trying to read a file and take the two columns of the file and put them respectively in their own arrays. Any help would be appreciated! Thanks!
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
// TODO Auto-generated method stub
System.out.println("Please enter the name of the file to be read");
String fileName = keyboard.nextLine();
Scanner chirping = null;//user input for file name
boolean fileValue = false; //this makes the value false until the correct file name is inputed
while(!fileValue) {
try {
FileReader dates = new FileReader(fileName); // connects to the user inputted file
chirping = new Scanner(dates); //scans the file
fileValue = true; //turns file value to true which takes us out of the while loop
}//end try
catch(IOException e) {
System.out.println("File Not Found, Please Try Again: ");
fileName = keyboard.nextLine();
}//end catch
}// end while
double[] dataSet = new double[30];
double[] chirpFreq = new double[30];
double[] temp = new double[30];
//double[] temp = new double[chirping.nextInt()];
for(int i = 0; chirping.hasNextDouble(); i++) {
dataSet[i] = chirping.nextDouble();
}
for(int j = 0; j <= dataSet.length; j++) {
if(j%2 == 0) {
chirpFreq[j] = dataSet[j];
}
else {
temp[j] = dataSet[j];
}
}
for(int i = 0; i <= chirpFreq.length; i++) {
System.out.print(chirpFreq[i]+ " ");
}
chirping.close();
}
//These are the values i am trying to sort into two separate arrays
20 88.6
16 71.6
19.8 93.3
18.4 84.3
17.1 80.6
15.5 75.2
14.7 69.7
17.1 82
15.4 69.4
16.2 83.3
15 79.6
17.2 82.6
16 80.6
17 83.5
14.4 76.3

I don't usually use nextDouble() to read files so i don't know what your problem is exactly, but you can refactor your code to this:
double[] firstColumn = new double[30];
double[] secondColumn = new double[30];
String line = "";
int i = 0;
// keep reading until there is nothing to read
while( (line = chirping.nextLine()) != null ) {
// this is a regex that splits the line into an array based on whitespace
// just use " " if your data is separated by space or "\t" if tab
String[] columns = line.split("\\s+");
firstColumn[i] = Double.parseDouble(columns[0]);
secondColumn[i++] = Double.parseDouble(columns[1]);
}
chirping.close();

Is it possible to write a text file in such a way that when read by the Java compiler, it will add a line break at certain points?

For my Java class, I'm working on a project that is essentially a database for MTG cards. I have to read from a file as part of the project, so I am reading the card information from a file, and then splitting the lines to put each different type of information together to form different object classes for the different types of cards. The main nitpicky issue I'm running into right now is that I need the card text to be on one line in the text file so I can read it line by line, but I'd prefer if it weren't all on one line when I print it to the console. Is there any way to add a character combination into the text of the file itself that will tell my compiler, "line break here," when it reads that, or am I out of luck? I know I could just use \n in the code to achieve this, but as I am looping through the file, there is no way to do so properly that I know of, as not every card's text needs line breaks inserted. If it matters, this is the chunk of my code that deals with that:
import java.io.BufferedReader;
import java.io.FileReader;
import java.util.Scanner;
public class MTG {
public static void main(String[] args) {
int creatureLength = 4;
//Prompt User
Scanner sc = new Scanner(System.in);
System.out.println("Welcome to the Magic: the Gathering card database. This tool currently supports Rare and Mythic Rare cards from the Throne of Eldraine Expansion.");
try {
System.out.println("\nSelect the card type you'd like to view.");
System.out.println(""
+ "(1)Creatures\n"
);
int choice = Integer.parseInt(sc.next());
//Choose type
//Creatures
if(choice == 1){
Creature[] creatures = creatureGen("textfiles/Creatures.txt", creatureLength);
System.out.println("\nViewing creatures. Which card would you like to view?: \n");
for(int k = 0; k < creatureLength; k++) {
System.out.println(
"(" + (k + 1) + ") " + creatures[k].getName());
}
int creatureChoice = Integer.parseInt(sc.next());
try {
System.out.println("\n" + creatures[(creatureChoice - 1)]);}
catch(Exception e) {
System.out.println("Input was not a specified number. Exiting...");
}
}
}
catch(NumberFormatException ex){
System.out.println("Input was not a specified number. Exiting...");
}
sc.close();
}
//Read Creature text file
public static Creature[] creatureGen(String path, int length) {
Creature[] creatures = new Creature[length];
try {
FileReader file = new FileReader(path);
BufferedReader reader = new BufferedReader(file);
String name[] = new String[length];
String cost[] = new String[length];
String color[] = new String[length];
String type[] = new String[length];
String cTypes[] = new String[length];
String tags[] = new String[length];
String text[] = new String[length];
int power[] = new int[length];
int toughness[] = new int[length];
for (int i = 0; i < length; i++) {
String line = reader.readLine();
if(line != null) {
name[i] = line.split("\\|")[0];
cost[i] = line.split("\\|")[1];
color[i] = line.split("\\|")[2];
type[i] = line.split("\\|")[3];
cTypes[i] = line.split("\\|")[4];
tags[i] = line.split("\\|")[5];
text[i] = line.split("\\|")[6];
power[i] = Integer.parseInt(line.split("\\|")[7]);
toughness[i] = Integer.parseInt(line.split("\\|")[8]);
creatures[i] = new Creature(name[i], cost[i], color[i], type[i], cTypes[i], tags[i], text[i], power[i], toughness[i]);
}
}
reader.close();
}
catch (Exception e) {
System.out.println("Error reading file: " + path);
}
return creatures;
}
}
The Creature object class essentially just stores the data that I am putting into it with the creatureGen method. A sample line from the text file I am reading from looks something like this:
Charming Prince|1W|White|Creature|Human Noble||When Charming Prince enters the battlefield, choose one — • Scry 2. • You gain 3 life. • Exile another target creature you own. Return it to the battlefield under your control at the beginning of the next end step.|2|2
It would be ideal to be able to insert line breaks after each of the bullet points in this card, for example, but as I said earlier, I need the text to be in one line for my loop to read it. Is there any way around this when I print this back to the console? I appreciate any help.

Just replace those bullet points with line breaks :
text[i] = line.split("\\|")[6].replaceAll("•","\n");
Also, you should not split each time you need an element, put the result of line.split("\|") in a String[] variable and use it afterwards.
for (int i = 0; i < length; i++) {
String line = reader.readLine();
if(line != null) {
String[] elements = line.split("\\|");
name[i] = elements[0];
cost[i] = elements[1];
color[i] = elements[2];
type[i] = elements3];
cTypes[i] = elements[4];
tags[i] = elements[5];
text[i] = elements[6].replaceAll("•","\n");
power[i] = Integer.parseInt(elements[7]);
toughness[i] = Integer.parseInt(elements[8]);
creatures[i] = new Creature(name[i], cost[i], color[i], type[i], cTypes[i], tags[i], text[i], power[i], toughness[i]);
}
}
Finally, about vocabulary, the compiler is not reading your file. The compiler translates your code into binary instructions for the processor (to summarize).
Your file is read at runtime.

When I run my code I get (0, null) and cant figure out why

I am creating a program that is reading a file of names and ages then printing them out in ascending order. I am parsing through the file to figure out the number of name age pairs and then making my array that big.
The input file looks like this:
(23, Matt)(2000, jack)(50, Sal)(47, Mark)(23, Will)(83200, Andrew)(23, Lee)(47, Andy)(47, Sam)(150, Dayton)
When I am running my code I get the output of (0,null) and I am not sure why. I have been trying to fix it for a while and am lost. If anyone can help that would be great My code is below.
public class ponySort {
public static void main(String[] args) throws FileNotFoundException {
int count = 0;
int fileSize = 0;
int[] ages;
String [] names;
String filename = "";
Scanner inputFile = new Scanner(System.in);
File file;
do {
System.out.println("File to read from:");
filename = inputFile.nextLine();
file = new File(filename);
//inputFile = new Scanner(file);
}
while (!file.exists());
inputFile = new Scanner(file);
if (!inputFile.hasNextLine()) {
System.out.println("No one is going to the Friendship is magic Party in Equestria.");
}
while (inputFile.hasNextLine()) {
String data1 = inputFile.nextLine();
String[] parts1 = data1.split("(?<=\\))(?=\\()");
for (String part : parts1) {
String input1 = part.replaceAll("[()]", "");
Integer.parseInt(input1.split(", ")[0]);
fileSize++;
}
}
ages = new int[fileSize];
names = new String[fileSize];
while (inputFile.hasNextLine()) {
String data = inputFile.nextLine();
String[] parts = data.split("(?<=\\))(?=\\()");
for (String part : parts) {
String input = part.replaceAll("[()]", "");
ages[count] = Integer.parseInt(input.split(", ")[0]);
names[count] = input.split(", ")[1];
count++;
}
}
ponySort max = new ponySort();
max.bubbleSort(ages, names, count);
max.printArray(ages, names, count);
}
public void printArray(int ages[], String names[], int count) {
System.out.print("(" + ages[0] + "," + names[0] + ")");
// Checking for duplicates in ages. if it is the same ages as one that already was put in them it wont print.
for (int i = 1; i < count; i++) {
if (ages[i] != ages[i - 1]) {
System.out.print("(" + ages[i] + "," + names[i] + ")");
}
}
}
public void bubbleSort(int ages[], String names[], int count ){
for (int i = 0; i < count - 1; i++) {
for (int j = 0; j < count - i - 1; j++) {
// age is greater so swaps age
if (ages[j] > ages[j + 1]) {
// swap the ages
int temp = ages[j];
ages[j] = ages[j + 1];
ages[j + 1] = temp;
// must also swap the names
String tempName = names[j];
names[j] = names[j + 1];
names[j + 1] = tempName;
}
}
}
}
}
output example
File to read from:
file.txt
(0,null)
Process finished with exit code 0

What your code does is to Scan the file twice.
In the first loop you do
String data1 = inputFile.nextLine();
Code reads first line and then scanner goes to the next (second) line.
Later you do again inputFile.nextLine(); The second line is empty and the code never goes into the second loop and content is never read.
If you can use Lists, you should create two array lists and add ages and names into the arraylists in the first scan, so you scan the file once. When done, you could get the Array out of the arraylist.
If you should only use arrays and you want a simple update, just add another Scanner before the second loop:
ages = new int[fileSize];
names = new String[fileSize];
inputFile = new Scanner(file); // add this line

How to print out a line in a textfile into 2 different lines on console Java

public static FAQ_Alisa_QnA[] oipReadQuestion(){
String questionA1,thisUser;
int indexQuestion;
String [] entryDetails;
FAQ_Alisa_QnA [] entries = new FAQ_Alisa_QnA[100];
//Read file = "activities.txt".
File file = new File ("ReadOIP.txt");
int count = 0;
try{
Scanner sc = new Scanner(file);
//do this while there is a next line in file.
while(sc.hasNextLine()){
String line = sc.nextLine();
entryDetails = line.split(";");
// index = entryDetails[0];
indexQuestion = Integer.parseInt(entryDetails[0]);
thisUser = entryDetails[1];
questionA1 = entryDetails[2];
//Object to store values of entry.
FAQ_Alisa_QnA a = new FAQ_Alisa_QnA();
// a.index = Integer.parseInt(index);
a.indexQuestion = indexQuestion;
a.thisUsername = thisUser;
a.questionA1 = questionA1;
entries [count] = a;
count++;
}
}catch(FileNotFoundException fnfe){
System.out.println(fnfe.getMessage());
}
FAQ_Alisa_QnA [] allQuestions = new FAQ_Alisa_QnA [count];
for(int i = 0; i < count; i++){
allQuestions[i] = entries[i];
}
return allQuestions;
}
public static FAQ_Alisa_QnA[] oipReadAnswers(){
String indexAnswer, answer11, thisUser;
String [] answerDetails;
FAQ_Alisa_QnA [] answers = new FAQ_Alisa_QnA[100];
//Read file = "activities.txt".
File thisFile = new File ("AnsReadOIP.txt");
int count1 = 0;
try{
Scanner sc1 = new Scanner(thisFile);
//do this while there is a next line in file.
while(sc1.hasNextLine()){
String line = sc1.nextLine();
answerDetails = line.split(";");
// index = entryDetails[0];
indexAnswer = answerDetails[0];
thisUser = answerDetails[1];
answer11 = answerDetails[2];
//Object to store values of entry.
FAQ_Alisa_QnA a = new FAQ_Alisa_QnA();
// a.index = Integer.parseInt(index);
a.indexAnswer = Integer.parseInt(indexAnswer);
a.thisUsername = thisUser;
a.answer11 = answer11;
answers [count1] = a;
count1++;
}
}catch(FileNotFoundException fnfe){
System.out.println(fnfe.getMessage());
}
FAQ_Alisa_QnA[] allAnswers = new FAQ_Alisa_QnA[count1];
for(int i = 0; i < count1; i++){
allAnswers[i] = answers[i];
}
return allAnswers;
}
public static void oipPrintQnA(){
FAQ_Alisa_QnA [] allQuestions = oipReadQuestion();
FAQ_Alisa_QnA [] allAnswers = oipReadAnswers();
System.out.println("Organization in project work");
System.out.println("=============================");
for(int i = 0; i < allQuestions.length; i++){
System.out.println( allQuestions[i].indexQuestion + "-" + "Question" + ":");
System.out.println(allQuestions[i].thisUsername + ":" +allQuestions[i].questionA1);
System.out.println(" ");
for(int j = 0; j < allAnswers.length; j++){
if(allQuestions[i].indexQuestion == allAnswers[j].indexAnswer){
System.out.println("Answer for question "+ + allAnswers[j].indexAnswer+ ":" );
System.out.println(allAnswers[j].thisUsername+ ":" +allAnswers[j].answer11);
System.out.println(" ");
}
}
}
}
//So I have read answers and questions and I saved my qns and answers in 2 different text files. This is because I have add functions to it but i never put it here cuz my qn is not related to that. I just wanna know how to print out the qn and answer in 2 lines so that if the qn is so long then it can print out in two lines//
So these are how my text files look like:
ReadOIP.txt
1;Shafiq;How to organize your time well when you're juggling with so many project work and assignments on the same day? Best answer:The best solution to this is to early planning or schedule your time wisely. Write in a calendar beforehand the work you are going to do for an assignment.
2;Rohannah;Does having a timetable works to finish your project on time?
3;lymeoww;Is task allocation really important to be organized in project work?
AnsReadOIP.txt
1;Andy23;The best solution to this is to early planning or schedule your time wisely. Write in a calendar beforehand the work you are going to do for an assignment .2; Does having a timetable to do your project works? //For example this line, it will print out very long on the console//
2;Betty23;of course it does!
1;Ying Qian;just organize lorh
3;lymeoww;Yes, it is important!
//Refer to this picture//

Reading from file/array. No values. No errors

Any ideas what I am missing here? I am reading from a file array. The values in the text file don't get stored and there is no output. All I get is "names and totals" but no values.
I don't know.
private int[] totals;
private String[] names;
private String[] list;
private int count;
public void readData() throws IOException {
BufferedReader input = new BufferedReader(new FileReader("cookies.txt"));
//create the arrays
totals = new int[count];
names = new String[count];
list = new String[count];
//read in each pair of values
String quantityString = input.readLine();
for (int i = 0; i < count; i++) {
names[i] = input.readLine();
list[i] = input.readLine();
quantityString = input.readLine();
totals[i] = Integer.parseInt(quantityString);
}
}
public void display() {
System.out.println("names totals")
for (int i = 0; i < count; i++)
System.out.println(list[i] + " \t " + names[i] + " \t" + totals[i]);
}
//called to compute and print the result
public void printResults() {
//find the best teacher
int maxIndex = 0;
int maxValue = 0;
//for each record stores
for (int i = 0; i < count; i++) {
//if we have a new MAX value so far, update variables
if (maxValue < totals[i]) {
maxValue = totals[i];
maxIndex = i;
}
}
}

You never give the variable count a value, so it initialized to 0 by Java. This means that your arrays are of size 0 also.
So since count is zero, you never read anything from the file, which is why nothing is stored in your arrays and also why nothing is printed out.
Example: Reading a File line-by-line
// create temporary variable to hold what is being read from the file
String line = "";
// when you don't know how many things you have to read in use a List
// which will dynamically grow in size for you
List<String> names = new ArrayList<String>();
List<Integer> values = new ArrayList<Integer>();
// create a Reader, to read from a file
BufferedReader input = new BufferedReader(new FileReader("cookies.txt"));
// read a full line, this means if you line is 'Smith 36'
// you read both of these values together
while((line = input.readLine()) != null)
{
// break 'Smith 36' into an array ['Smith', '36']
String[] nameAndValue = line.split("\\s+");
names.add(nameAndValue[0]); // names.add('Smith')
values.add(Integer.parseInt(nameAndValue[1]); // values.add(36);
}