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Javafx: Reading from an File and Spliting the result with .split method

I want to by reading the data of a file to split the results based on .split(",") in another words for this particular example i want to have 2 Indexes with each containing up to 5 informations which i would also like to acces with the .[0] and .[1] Method.
the File with the Data.
File Reading Method.
public void fileReading(ActionEvent event) throws IOException {
File file = new File("src/DateSpeicher/datenSpeicher.txt");
BufferedReader br = new BufferedReader(new FileReader(file));
String st;
while ((st = br.readLine()) != null) {
System.out.println(st);
}
}
The method does work very greatly however, i wonder how can i split those two in two Indexes or String arrays which both can be accessed through respective indecies [0], [1]. For first data in the firm array - 655464 [0][0] for last in the second Array [1][4].
My approach:
1. Making an ArrayList for every ,
2. Adding data till ","
Issue: eventho approach above works, you cant do such things as array1[0] - it gives an error, however the index method is crucial.
How can i solve this problem?

Path path = Paths.get("src/DateSpeicher/datenSpeicher.txt"); // Or:
Path path = Paths.get(new URL("/DateSpeicher/datenSpeicher.txt").toURI());
Either two Strings, and then handling them:
String content = new String(Files.readAllBytes(path), Charset.defaultCharset());
String[] data = content.split(",\\R");
or a list of lists:
List<String> lines = Files.readAllLines(path, Charset.defaultCharset());
// Result:
List<List<String>> lists = new ArrayList<>();
List<String> newList = null;
boolean addNewList = true;
for (int i = 0; i < lines.size(); ++i) {
if (addNewList) {
newList = new ArrayList<>();
lists.add(newList);
addNewList = false;
}
String line = lines.get(i);
if (line.endsWith(",")) {
line = line.substring(0, line.length() - 1);
addNewList = true;
}
newList.add(line);
}

Read Tab-Separated-Columns into Lists - Java

Tab-Separated File:
2019-06-06 10:00:00 1.0
2019-06-06 11:00:00 2.0
I'd like to iterate over the file once and add the value of each column to a list.
My working approach would be:
import java.util.*;
import java.io.*;
public class Program {
public static void main(String[] args)
{
ArrayList<Double> List_1 = new ArrayList<Double>();
ArrayList<Double> List_2 = new ArrayList<Double>();
String[] values = null;
String fileName = "File.txt";
File file = new File(fileName);
try
{
Scanner inputStream = new Scanner(file);
while (inputStream.hasNextLine()){
try {
String data = inputStream.nextLine();
values = data.split("\\t");
if (values[1] != null && !values[1].isEmpty() == true) {
double val_1 = Double.parseDouble(values[1]);
List_1.add(val_1);
}
if (values[2] != null && !values[2].isEmpty() == true) {
double val_2 = Double.parseDouble(values[2]);
List_2.add(val_2);
}
}
catch (ArrayIndexOutOfBoundsException exception){
}
}
inputStream.close();
}
catch (FileNotFoundException e) {
e.printStackTrace();
}
System.out.println(List_1);
System.out.println(List_2);
}
}
I get:
[1.0]
[2.0]
It doesn't work without the checks for null, ìsEmpty and the ArrayIndexOutOfBoundsException.
I would appreciate any hints on how to save a few lines while keeping the scanner approach.

One option is to create a Map of Lists using column number as a key. This approach gives you "unlimited" number of columns and exactly the same output than one in the question.
public class Program {
public static void main(String[] args) throws Exception
{
Map<Integer, List<Double>> listMap = new TreeMap<Integer, List<Double>>();
String[] values = null;
String fileName = "File.csv";
File file = new File(fileName);
Scanner inputStream = new Scanner(file);
while (inputStream.hasNextLine()){
String data = inputStream.nextLine();
values = data.split("\\t");
for (int column = 1; column < values.length; column++) {
List<Double> list = listMap.get(column);
if (list == null) {
listMap.put(column, list = new ArrayList<Double>());
}
if (!values[column].isEmpty()) {
list.add(Double.parseDouble(values[column]));
}
}
}
inputStream.close();
for(List<Double> list : listMap.values()) {
System.out.println(list);
}
}
}

You can clean up your code some by using try-with resources to open and close the Scanner for you:
try (Scanner inputStream = new Scanner(file))
{
//your code...
}
This is useful because the inputStream will be closed automatically once the try block is left and you will not need to close it manually with inputStream.close();.
Additionally if you really want to "save lines" you can also combine these steps:
double val_2 = Double.parseDouble(values[2]);
List_2.add(val_2);
Into a single step each, since you do not actually use the val_2 anywhere else:
List_2.add(Double.parseDouble(values[2]));
Finally you are also using !values[1].isEmpty() == true which is comparing a boolean value to true. This is typically bad practice and you can reduce it to !values[1].isEmpty() instead which will have the same functionality. Try not to use == with booleans as there is no need.

you can do it like below:
BufferedReader bfr = Files.newBufferedReader(Paths.get("inputFileDir.tsv"));
String line = null;
List<List<String>> listOfLists = new ArrayList<>(100);
while((line = bfr.readLine()) != null) {
String[] cols = line.split("\\t");
List<String> outputList = new ArrayList<>(cols);
//at this line your expected list of cols of each line is ready to use.
listOfLists.add(outputList);
}
As a matter of fact, it is a simple code in java. But because it seems that you are a beginner in java and code like a python programmer, I decided to write a sample code to let you have a good start point. good luck

Reading from csv files

This is a project i'm working on at college, everything seems good except in the game class which initializes the game. Here is a snippet
public class Game{
private Player player;
private World world;
private ArrayList<NonPlayableFighter> weakFoes;
private ArrayList<NonPlayableFighter> strongFoes;
private ArrayList<Attack> attacks;
private ArrayList<Dragon> dragons;
public Game() throws IOException{
player = new Player("");
world = new World();
weakFoes = new ArrayList<NonPlayableFighter>();
strongFoes = new ArrayList<NonPlayableFighter>();
attacks = new ArrayList<Attack>();
dragons = new ArrayList<Dragon>();
loadAttacks ("Database-Attacks_20309.csv");
loadFoes ("Database-Foes_20311.csv");
loadDragons ("Database-Dragons_20310.csv");
}
after that follows some getters and the 4 method i am supposed to implement.
These methods are loadCSV(String filePath),loadAttacks(String filePath),loadFoes(String filePath),loadDragons(String filePath)
I have created loadCSV(String filePath) such that it returns an ArrayList of String[] here:
private ArrayList<String[]> loadCSV(String filePath) throws IOException{
String currentLine = "";
ArrayList<String[]> result = new ArrayList<String[]>();
FileReader fileReader = new FileReader(filePath);
BufferedReader br = new BufferedReader(fileReader);
currentLine = br.readLine();
while (currentLine != null){
String[] split = currentLine.split(",");
result.add(split);
}
br.close();
return result;
}
Then i would like to load some attacks, foes, and dragons and inserting them in the appropriate ArrayList.
I applied loadAttacks(String filePath) here:
private void loadAttacks(String filePath) throws IOException{
ArrayList<String[]> allAttacks = loadCSV(filePath);
for(int i = 0; i < allAttacks.size(); i++){
String[] current = allAttacks.get(i);
Attack temp = null;
switch(current[0]){
case "SA": temp = new SuperAttack(current[1],
Integer.parseInt(current[2]));
break;
case "UA": temp = new UltimateAttack(current[1],
Integer.parseInt(current[2]));
break;
case "MC": temp = new MaximumCharge();
break;
case "SS": temp = new SuperSaiyan();
break;
}
attacks.add(temp);
}
}
I wrote it such that it takes the ArrayList returned from loadCSV(String filePath) and searches in each String[] within the ArrayList on the first String using a switch thus creating the appropriate attack and adding it to attacks.
Then i would like to read another CSV for the Foes and the CSV file is structured such that in the first line there are some attributes the second line some attacks of type SuperAttack and the third line holds some attacks of type Ultimate attack. Also within each foe there is a boolean attribute that determines if it is a Strong or Weak Foe thus putting it in the right Arraylist. Here is the code for loadFoes(String filePath):
private void loadFoes(String filePath) throws IOException{
ArrayList<String[]> allFoes = loadCSV(filePath);
for(int i = 0; i < allFoes.size(); i += 3){
String[] current = allFoes.get(i);
String[] supers = allFoes.get(i+1);
String[] ultimates = allFoes.get(i+2);
ArrayList<SuperAttack> superAttacks = new ArrayList<SuperAttack>();
ArrayList<UltimateAttack> ultimateAttacks = new ArrayList<UltimateAttack>();
NonPlayableFighter temp = null;
for(int j = 0; i < supers.length; j++){
int index = attacks.indexOf(supers[j]);
if(index != -1){
superAttacks.add((SuperAttack)attacks.get(index));
}
else break;
}
for(int j = 0; i < ultimates.length; j++){
int index = attacks.indexOf(ultimates[j]);
if(index != -1){
ultimateAttacks.add((UltimateAttack)attacks.get(index));
}
else break;
}
if(current[7].equalsIgnoreCase("True")){
temp = new NonPlayableFighter(current[0], Integer.parseInt(current[1]),
Integer.parseInt(current[2]), Integer.parseInt(current[3]),
Integer.parseInt(current[4]), Integer.parseInt(current[5]),
Integer.parseInt(current[6]), true, superAttacks, ultimateAttacks);
strongFoes.add(temp);
}
else{
temp = new NonPlayableFighter(current[0], Integer.parseInt(current[1]),
Integer.parseInt(current[2]), Integer.parseInt(current[3]),
Integer.parseInt(current[4]), Integer.parseInt(current[5]),
Integer.parseInt(current[6]), false, superAttacks, ultimateAttacks);
weakFoes.add(temp);
}
}
}
First i get the first three String[] in the ArrayList returned from loadCSV(String filePath and made 2 loops to check if the attacks are within the previously loaded attacks CSV then i check for the attribute that determines if it is a strong or weak and accordingly creating a new NonPlayableFighter and adding it to the appropriate list.
Running the jUnit4 tests for this assignment it gives me a Compilation Error: Unhandled exception type IOException. And generally speaking does the code have any notable problems ?

It's better to reuse already exist CSV file readers for Java (e.g. CVSReader) if isn't a part of you task.

That makes a lot of code. I'll answer to your Compilation Error.
While reading a file you have to pu your code in a try catch in order to avoid this kind of error. In your loadCSV method you have to set up a try catch block.
Please refer to this site for complete tutorial.
try (BufferedReader br = new BufferedReader(new FileReader("C:\\testing.txt")))
{
String sCurrentLine;
while ((sCurrentLine = br.readLine()) != null) {
String[] split = currentLine.split(",");
result.add(split);
}
} catch (IOException e) {
e.printStackTrace();
}
To make it short, code that access to files have to be in a try catch to avoid IO Exception, or be in a method that throws the exception (but then it has to be catched elsewhere).
In that code you have a good example of a try-with-resource, very good way to manage your ressource and memory.

loadCSV(String filePath) is a infinite loop isn't it? And as for the IOException it as #RPresle suggested a try/catch would do the trick around the BufferedReader.

Java one same name can be occured in combobox

How can I have only one same name in my combobox? There are 2 same name in my fee text file and I want to get the name from fee text file to the combobox. But it display 2 same name.
There are no error in my code and I cannot find out the questions. I think my combobox function got problems. Below is my expected result.
//fee.txt
john|123|0.00
john|456|0.00
//my expected result in combobox
john
//my result
john
john
//filefuncion.java
public class FileFunction {
public static ArrayList getContent(File f) {
ArrayList ls = null;
try (BufferedReader in = new BufferedReader(new FileReader(f));) {
String line;
ls = new ArrayList();
/*while ((line = in.readLine()) != null) {
ls.add(line);
}*/
while ((line = in.readLine()) != null) {
if (line.trim().length() > 0) {
ls.add(line);
}
}
} catch (Exception e) {
e.printStackTrace();
}
return ls;
}
//my code
private void combobox(){
File file = new File("fee.txt");
ArrayList al = FileFunction.getContent(file);
for (Object obj : al) {
String newobj = obj.toString();
String text[] = newobj.split("\\|");
String name = text[0];
String status = text[2];
if(status.equals("0.00")){
comboboxResident.addItem(name);
}
}
}

First, use generics to ensure a stronger type-checking and reduce bugs due to incorrect types. Write something like ArrayList<String> instead of plain ArrayList.
If you want to remove duplicate elements in an ArrayList instance, the most convenient way is to build a Set (which is a class under the Collection framework) and convert it back to ArrayList (if you need to).
For example, suppose you have an ArrayList instance, then you may write
ArrayList<String> list = ...
LinkedHashSet<String> set = new LinkedHashSet<>(list);
Just iterate through set will do. Or you can convert it back to a list by ArrayList<String> newList = new ArrayList<>(set);.
A LinkedHashSet implements the Set interface and does not contain duplicate elements. It also has predictable iteration order. If you want to further sort you elements, try a TreeSet instead.

Compare values in two files

I have two files Which should contain the same values between Substring 0 and 10 though not in order. I have Managed to Outprint the values in each file but I need to Know how to Report say id the Value is in the first File and Notin the second file and vice versa. The files are in these formats.
6436346346....Other details
9348734873....Other details
9349839829....Other details
second file
8484545487....Other details
9348734873....Other details
9349839829....Other details
The first record in the first file does not appear in the second file and the first record in the second file does not appear in the first file. I need to be able to report this mismatch in this format:
Record 6436346346 is in the firstfile and not in the secondfile.
Record 8484545487 is in the secondfile and not in the firstfile.
Here is the code I currently have that gives me the required Output from the two files to compare.
package compare.numbers;
import java.io.*;
/**
*
* #author implvcb
*/
public class CompareNumbers {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
File f = new File("C:/Analysis/");
String line;
String line1;
try {
String firstfile = "C:/Analysis/RL001.TXT";
FileInputStream fs = new FileInputStream(firstfile);
BufferedReader br = new BufferedReader(new InputStreamReader(fs));
while ((line = br.readLine()) != null) {
String account = line.substring(0, 10);
System.out.println(account);
}
String secondfile = "C:/Analysis/RL003.TXT";
FileInputStream fs1 = new FileInputStream(secondfile);
BufferedReader br1 = new BufferedReader(new InputStreamReader(fs1));
while ((line1 = br1.readLine()) != null) {
String account1 = line1.substring(0, 10);
System.out.println(account1);
}
} catch (Exception e) {
e.fillInStackTrace();
}
}
}
Please help on how I can effectively achieve this.
I think I needed to say that am new to java and may not grab the ideas that easily but Am trying.

Here is the sample code to do that:
public static void eliminateCommon(String file1, String file2) throws IOException
{
List<String> lines1 = readLines(file1);
List<String> lines2 = readLines(file2);
Iterator<String> linesItr = lines1.iterator();
while (linesItr.hasNext()) {
String checkLine = linesItr.next();
if (lines2.contains(checkLine)) {
linesItr.remove();
lines2.remove(checkLine);
}
}
//now lines1 will contain string that are not present in lines2
//now lines2 will contain string that are not present in lines1
System.out.println(lines1);
System.out.println(lines2);
}
public static List<String> readLines(String fileName) throws IOException
{
List<String> lines = new ArrayList<String>();
FileInputStream fs = new FileInputStream(fileName);
BufferedReader br = new BufferedReader(new InputStreamReader(fs));
String line = null;
while ((line = br.readLine()) != null) {
String account = line.substring(0, 10);
lines.add(account);
}
return lines;
}

Perhaps you are looking for something like this
Set<String> set1 = new HashSet<>(FileUtils.readLines(new File("C:/Analysis/RL001.TXT")));
Set<String> set2 = new HashSet<>(FileUtils.readLines(new File("C:/Analysis/RL003.TXT")));
Set<String> onlyInSet1 = new HashSet<>(set1);
onlyInSet1.removeAll(set2);
Set<String> onlyInSet2 = new HashSet<>(set2);
onlyInSet2.removeAll(set1);

If you guarantee that the files will always be the same format, and each readLine() function is going to return a different number, why not have an array of strings, rather than a single string. You can then compare the outcome with greater ease.

Ok, first I would save the two sets of strings in to collections
Set<String> s1 = new HashSet<String>(), s2 = new HashSet<String>();
//...
while ((line = br.readLine()) != null) {
//...
s1.add(line);
}
Then you can compare those sets and find elements that do not appear in both sets. You can find some ideas on how to do that here.
If you need to know the line number as well, you could just create a String wrapper:
class Element {
public String str;
public int lineNr;
public boolean equals(Element compElement) {
return compElement.str.equals(str);
}
}
Then you can just use Set<Element> instead.

Open two Scanners, and :
final TreeSet<Integer> ts1 = new TreeSet<Integer>();
final TreeSet<Integer> ts2 = new TreeSet<Integer>();
while (scan1.hasNextLine() && scan2.hasNexLine) {
ts1.add(Integer.valueOf(scan1.nextLigne().subString(0,10));
ts1.add(Integer.valueOf(scan1.nextLigne().subString(0,10));
}
You can now compare ordered results of the two trees
EDIT
Modified with TreeSet

Put values from each file to two separate HashSets accordingly.
Iterate over one of the HashSets and check whether each value exists in the other HashSet. Report if not.
Iterate over other HashSet and do same thing for this.