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Set boolean to true, but filewriter still overwrites the file, any advice?

I have created a simple program that sorts integers in an input file using different algorithms. I also use filewriter to output results to another file. Unfortunately no matter how I change my code, file gets overridden. Any advice?
Been searching for answer on google and tried changing the way I input the syntax but nothing works.
important bits:
setting the writer up
try {
FileWriter fileWriter = new FileWriter ("Sorted output.txt");
//BufferedWriter bufferedWriter = new BufferedWriter (fileWriter);
PrintWriter out = new PrintWriter (new FileWriter("Sorted output.txt", true));
outputting to the file
out.println("User's own data set sorted using bubble sort.");
out.println(unsortedArray + Arrays.deepToString(FileOne));
out.println("Sorted Array looks like this:" + Arrays.toString(intArrayBubble));
out.println(timeToSort + bubbleSortIs + bubbleTime + "ms");
it works fine, however its used in a do while loop, with nested if statements, and each one overrides the other.
Rest of code in case its required - UPDATED - still not working
import java.io.*;
import java.util.*;
import java.util.concurrent.TimeUnit;
public class PDD_Sorting {
public static void main (String [] pArgs)
{
//Array for a file
String[] FileOne;
FileOne = new String[0];
int optionOne = 1,
optionTwo = 2,
optionThree = 3,
secondaryOptionOne = 1,
secondaryOptionTwo = 2,
secondaryOptionThree = 3,
userSelection,
subUserSelection;
String unsortedArray = "Unsorted array is: ",
bubbleSort = "Sorted array using bubble sort: ",
selectionSort = "Sorted array using selection sort: ",
insertionSort = "Sorted array using insertion sort: ",
timeToSort = "Time needed to sort this array using ",
bubbleSortIs = "bubble sort is ",
selectionSortIs = "selection sort is ",
insertionSortIs = "insertion sort is ",
welcomeToSorter = "Welcome to the SORTER - program that can sort your txt files containing integeres in an ascending order!",
notFiles = "Integers, not files :)",
pleaseSelect = "Please select one of the following options, by enetering a number asociated with it.",
optionOneUserInput = "1. Sort your own data set - input your own set of data (integers, separated by colons, no spaces) into the Input file.",
optionTwoPredefined = "2. Use predetermind set of data to test the algorythms.",
optionThreeExit = "3. Exit the program.",
subMenuPleaseSelect = "Please select which algorythm would you like to use to sort this file.",
optionBubble = "(1) - Bubble Sort.",
optionSelection = "(2) - Selection Sort.",
optionInsertion = "(3) - Insertion Sort.",
usersDataBubble = "User's own data set sorted using bubble sort.",
sortedArrayLooks = "Sorted Array looks like this:",
msTime = "ms",
usersDataSelection = "User's own data set sorted using selection sort.",
usersDataInsertion = "User's own data set sorted using insertion sort.",
validOption = "Please enter a valid option i.e. 1,2 or 3",
lessThanZero = "If time shown in ms is 0, that means the time needed to conduct the sort is shorter than 1ms.",
fileCreated = "File created.",
terminatingProgram = "Terminating the program.",
unableToWriteFile = "Unable to write to file";
System.out.println(welcomeToSorter);
System.out.println(notFiles);
Scanner tInput = new Scanner (System.in);
try {
FileWriter fileWriter = new FileWriter ("Sorted output.txt");
//BufferedWriter bufferedWriter = new BufferedWriter (fileWriter);
PrintWriter out = new PrintWriter (new FileWriter("Sorted output.txt", true));
do {
System.out.println(pleaseSelect);
System.out.println(optionOneUserInput);
System.out.println(optionTwoPredefined);
System.out.println(optionThreeExit);
// Scanner tInput = new Scanner (System.in);
userSelection = tInput.nextInt();
if (userSelection == optionOne) {
//System.out.println("Please enter a valid path for your file.");
String[] splitFile = null;
//String userFile = tInput.next();
FileOne = getAndPrepareFile(splitFile);
System.out.println(subMenuPleaseSelect);
System.out.println(optionBubble);
System.out.println(optionSelection);
System.out.println(optionInsertion);
subUserSelection = tInput.nextInt();
if (subUserSelection == secondaryOptionOne) {
int size = FileOne.length;
int [] intArrayBubble = new int [size];
for(int i=0; i<size; i++) {
intArrayBubble[i] = Integer.parseInt(FileOne[i]);
}
bubbleSort(intArrayBubble);
long bubbleTime = timeCount(intArrayBubble);
out.println(usersDataBubble);
out.println(unsortedArray + Arrays.deepToString(FileOne));
out.println(sortedArrayLooks + Arrays.toString(intArrayBubble));
out.println(timeToSort + bubbleSortIs + bubbleTime + msTime);
}
else if (subUserSelection == secondaryOptionTwo) {
int size2 = FileOne.length;
int [] intArraySelection = new int [size2];
for(int i=0; i<size2; i++) {
intArraySelection[i] = Integer.parseInt(FileOne[i]);
}
doSelectionSort(intArraySelection);
long selectionTime = timeCount(intArraySelection);
out.println(usersDataSelection);
out.println(unsortedArray + Arrays.deepToString(FileOne));
out.println(sortedArrayLooks + Arrays.toString(intArraySelection));
out.println(timeToSort + selectionSortIs + selectionTime + msTime);
}
else if (subUserSelection == secondaryOptionThree) {
int size3 = FileOne.length;
int [] intArrayInsertion = new int [size3];
for(int i=0; i<size3; i++) {
intArrayInsertion[i] = Integer.parseInt(FileOne[i]);
}
doInsertionSort(intArrayInsertion);
long insertionTime = timeCount(intArrayInsertion);
out.println(usersDataInsertion);
out.println(unsortedArray + Arrays.deepToString(FileOne));
out.println(sortedArrayLooks + Arrays.toString(intArrayInsertion));
out.println(timeToSort + insertionSortIs + insertionTime + msTime);
}
else {
System.out.println(validOption);
tInput.next();
}
}
else if (userSelection == optionTwo){
//file being prepared and loaded via function
String[] splitFilePredefined = null;
FileOne = getAndPrepareFilePredefined(splitFilePredefined);
//converting string array into int array so the method can sort it.
int size = FileOne.length;
int [] intArrayBubble = new int [size];
for(int i=0; i<size; i++) {
intArrayBubble[i] = Integer.parseInt(FileOne[i]);
}
int size2 = FileOne.length;
int [] intArraySelection = new int [size2];
for(int i=0; i<size2; i++) {
intArraySelection[i] = Integer.parseInt(FileOne[i]);
}
int size3 = FileOne.length;
int [] intArrayInsertion = new int [size3];
for(int i=0; i<size3; i++) {
intArrayInsertion[i] = Integer.parseInt(FileOne[i]);
}
//inserting pre-prepared int arrays into variables including a timecount method
int bubbleTime = timeCount(intArrayBubble);
int selectionTime = timeCount(intArraySelection);
int insertionTime = timeCount(intArrayInsertion);
//sorting array using various sorts
bubbleSort(intArrayBubble);
doSelectionSort(intArraySelection);
doInsertionSort(intArrayInsertion);
//out.println("Sorted arrray using insertion sort looks like this: " + Arrays.toString(intArrayInsertion));
out.println(timeToSort + bubbleSortIs + bubbleTime + "ms");
out.println(timeToSort + selectionSortIs + selectionTime + "ms");
out.println(timeToSort + insertionSortIs + insertionTime + "ms");
out.println(lessThanZero);
System.out.println(fileCreated);
}
else if (userSelection == optionThree){
System.out.println(terminatingProgram);
System.exit(0);
}
else {
System.out.println(validOption);
tInput.next();
}
out.flush();
out.close();
//tInput.close();
}while (userSelection != optionThree);
}
catch (Exception e)
{
System.out.println(unableToWriteFile);
tInput.next();
}
tInput.close();
}//end main
//method that fetches the file from predefined, hardcoded location and removes comas, esentially prepares the file for the next phase
private static String[] getAndPrepareFile (String[] splitFile)
{
Scanner fileIn = null;
try
{
fileIn = new Scanner(new FileInputStream("C:\\Users\\Greg\\Documents\\Programming\\PDD - Assignment 1\\Input.txt"));
String fileNew = fileIn.next();
splitFile = fileNew.split(",");
//System.err.println(Arrays.toString(splitFile)); //Arrays.toString needed to print the array correctly, otherwise it prints the address of the object
fileIn.close();
}
catch (IOException e)
{
System.out.println("File not found.");
//System.exit(0);
}
return splitFile;
}
//as above but works for predefined file, that can be generated using randomNumber.java program
private static String[] getAndPrepareFilePredefined (String[] splitFilePredefined)
{
Scanner fileIn = null;
try
{
fileIn = new Scanner(new FileInputStream("C:\\Users\\Greg\\Documents\\Programming\\PDD - Assignment 1\\Generated input.txt"));
String fileNew = fileIn.next();
splitFilePredefined = fileNew.split(",");
//System.err.println(Arrays.toString(splitFile)); //Arrays.toString needed to print the array correctly, otherwise it prints the address of the object
fileIn.close();
}
catch (IOException e)
{
System.out.println("File not found.");
//System.exit(0);
}
return splitFilePredefined;
}
//method used to sort a file using bubble sort
private static void bubbleSort(int[] arr) {
int n = arr.length;
int temp = 0;
for(int i=0; i < n; i++){
for(int j=1; j < (n-i); j++){
if(arr[j-1] > arr[j]){
//swap elements
temp = arr[j-1];
arr[j-1] = arr[j];
arr[j] = temp;
}
}
}
}
//method used to sort a file using selection sort
private static int[] doSelectionSort(int[] arr){
for (int i = 0; i < arr.length - 1; i++)
{
int index = i;
for (int j = i + 1; j < arr.length; j++)
if (arr[j] < arr[index])
index = j;
int smallerNumber = arr[index];
arr[index] = arr[i];
arr[i] = smallerNumber;
}
return arr;
}
//method used to sort a file using sinsertion sort
private static int[] doInsertionSort(int[] input){
int temp;
for (int i = 1; i < input.length; i++) {
for(int j = i ; j > 0 ; j--){
if(input[j] < input[j-1]){
temp = input[j];
input[j] = input[j-1];
input[j-1] = temp;
}
}
}
return input;
}
//method used to calculate how much time has lapsed while using any of the given sort methods, outputs in ms, if less than 1 ms, outputs 0ms
private static int timeCount (int[] anArray)
{
long start = System.nanoTime();
Arrays.sort(anArray);
long end = System.nanoTime();
long timeInMillis = TimeUnit.MILLISECONDS.convert(end - start, TimeUnit.NANOSECONDS);
//System.out.println("Time spend in ms: " + timeInMillis);
return (int) timeInMillis;
}
}//end class
File gets constantly overridden, how do i stop this and make it add to file instead?

You don't need the first FileWriter fileWriter = new FileWriter("Sorted output.txt");; this is actually creating/overwriting the file, after which your PrintWriter opens it again for appending.
So, just change
// ... omitting beginning
try {
FileWriter fileWriter = new FileWriter ("Sorted output.txt");
//BufferedWriter bufferedWriter = new BufferedWriter (fileWriter);
PrintWriter out = new PrintWriter (new FileWriter("Sorted output.txt", true));
do {
// ... omitting rest
to
// ... omitting beginning
try {
//BufferedWriter bufferedWriter = new BufferedWriter (fileWriter);
PrintWriter out = new PrintWriter (new FileWriter("Sorted output.txt", true));
do {
// ... omitting rest

Move out.close() outside the loop
else {
System.out.println("Please enter a valid option i.e. 1,2 or 3");
tInput.next();
}
out.flush();
/* THIS -> out.close(); <- THIS */
//tInput.close();
}while (userSelection != optionThree);
out.close();
}
I tried your code and your problem is not that the file is being overwritten, but that you are closing the outputstream in the first iteration.

JAVA :Unable to view println after the while loop

I'm unable to view the println after exiting the "For" and "While" loop.
What am i doing wrong?
Assignment is : to Extract doubles from a txt file that has the numbers split by a "," . once i have the data do some calculations and display it. I've done all except the displaying. which I'm having some difficulty in.
try {
FileInputStream ofile = new FileInputStream("Sales Analysis.txt");
DataInputStream in = new DataInputStream(ofile);
BufferedReader Rreader = new BufferedReader( new InputStreamReader(in));
String Filedata ;
String read;
double[] TotalWeekSales = new double [7];
double[] DailyAverage = new double [7];
double TotalSales = 0;
double[] amount= new double [7];
double AverageSales = 0;
int Topsale = -1 ; // Position of Highest Week Sale
int LowestSale= -1; // Lowest Week Sale
while ((Filedata= Rreader.readLine()) != null) {
String[] Splitt = Filedata.split(",");
//double amount[] =new double [10];
for (int i = 0; i<Filedata.length(); i++)
{
read = Splitt[i];
amount[i] = Double.parseDouble(read);
TotalWeekSales[i] = amount[i];
DailyAverage[i]= (amount[i]/7);
TotalSales += amount[i];
System.out.println("\nWeek: "+(i+1));
System.out.println("\nAmount : $"+amount[i]);
}
};
/********* This part below doesn't Print ***********/
AverageSales = (TotalSales/7);
System.out.println("\nTotal Average Sales: $"+AverageSales);
} catch (Exception e) {
// TODO: handle exception
}
}
}

for (int i = 0; i<Filedata.length(); i++)
should be:
for (int i = 0; i < Splitt.length; i++)
there might be other bugs as well.
Note: it's difficult to read the code since it's not indented properly.

List<String[]> method Adding always same values

In my Java Project, i want to read values from txt file to List method.Values seems like;
1 kjhjhhkj 788
4 klkkld3 732
89 jksdsdsd 23
Number of row changable. I have tried this codes and getting same values in all indexes.
What can i do?
String[] dizi = new String[3];
List<String[]> listOfLists = new ArrayList<String[]>();
File f = new File("input.txt");
try {
Scanner s = new Scanner(f);
while (s.hasNextLine()) {
int i = 0;
while (s.hasNext() && i < 3) {
dizi[i] = s.next();
i++;
}
listOfLists.add(dizi);
}
} catch (FileNotFoundException e) {
System.out.println("Dosyaya ba?lanmaya çal???l?rken hata olu?tu");
}
int q = listOfLists.size();
for (int z = 0; z < q; z++) {
for (int k = 0; k < 3; k++) {
System.out.print(listOfLists.get(z)[k] + " ");
}
}

String [] dizi = new String [3];
dizi is a global variable getting overridden eveytime in the loop. Thats why you are getting same values at all indexes
Make a new instance everytime before adding to the list.

You put the same reference to the list, create a new array in while loop.
while (s.hasNextLine()){
String[] dizi = new String[3]; //new array
int i = 0;
while (s.hasNext() && i < 3)
{
dizi[i] = s.next();
i++;
}
listOfLists.add(dizi);
}

Adding multiple arraylist integers together

UPDATED:
After making the changes using Mike Kobit's answer, i wanted to move the files that i have already calculated to a different folder. the files do not successfully move and i dont know why? Does it have to do with the array list locking the files?
public static void main(String[] args) throws FileNotFoundException {
fSplit(path);
Date date = new Date();
SimpleDateFormat d = new SimpleDateFormat("yyyyMMdd_HHmmSS");
String d_f = d.format(date);
System.out.println(allSums);
try {
File fold = new File(path);
for(File k : fold.listFiles()) {
System.out.println(k.getName());
if(k.getName().contains("file")) { //named files read to be moved
boolean success = k.renameTo(new File(path2 + "\\" + k.getName()));
if(!success) {
System.out.println("FAILED MOVE");
}
}
}
} catch(Exception e) { e.printStackTrace(); }
}
private static void fSplit(String path) throws FileNotFoundException {
//ArrayList<Integer> allSums = new ArrayList<>();
//ArrayList<List<Integer>> allLists = new ArrayList<>();
File folder = new File(path);
for (File f : folder.listFiles()) {
//System.out.println(f.getName());
BufferedReader br = new BufferedReader(new FileReader(path + "\\" + f.getName()));
Scanner scanner = new Scanner(br);
ArrayList<Integer> list = new ArrayList<Integer>();
while(scanner.hasNext()) {
list.add(scanner.nextInt());
}
// Store each read list into a container for all of the lists
allLists.add(list);
//System.out.println(list);
}
// Assuming all lists are the same size
//int listLength = allLists.get(0).size();
// Iterate over each index
for(int i = 0; i < 5; i++) {
int sum = 0;
// For each index, add the elements from that index in each list
for(List<Integer> list : allLists) {
sum += list.get(i);
}
// Add the current indexes sum to the final list
allSums.add(sum);
}
}

You need to keep track of your arrays and then you can iterate over them. Here is your example with added comments and how you could sum up the elements after.
ArrayList<Integer> allSums = new ArrayList<>();
ArrayList<List<Integer>> allLists = new ArrayList<>();
for (File f : folder.listFiles()) {
BufferedReader br = new BufferedReader(new FileReader(path + "\\" + f.getName()));
Scanner scanner = new Scanner(br);
ArrayList<Integer> list = new ArrayList<Integer>();
while (scanner.hasNext()) {
list.add(scanner.nextInt());
}
// Store each read list into a container for all of the lists
allLists.add(list);
System.out.println(list);
}
// Assuming all lists are the same size
final int listLength = allLists.get(0).size();
// Iterate over each index
for (int i = 0; i < listLength; i++) {
int sum = 0;
// For each index, add the element from that index in each list
for (List<Integer> list : allLists) {
sum += list.get(i);
}
// Add the current indexes sum to the final list
allSums.add(sum);
}
// allSums contains the sum from every index
// Using Java 8 streams
allSums.clear();
IntStream.range(0, listLength)
.forEach((i) -> allSums.add(i, allLists.stream().collect(Collectors.summingInt((c) -> c.get(i)))));
System.out.println(allSums);
Output from both ways:
[11, 12, 6, 5, 11]
[11, 12, 6, 5, 11]

If you want to add using ArrayList you can do this
List<Integer> sum = new ArrayList<Integer>(5);
for (int i = 0; i < sum.size(); i++) {
sum.add(i, list1.get(i) + list2.get(i) + list3.get(i));
}

Explantion:In the for loop you will add all same index elements in different array with each other and save it in same index at result array
Note:
my code is done with array but I am sure you can change it to arraylist very easily
Code:
List<Integer> list1 = Arrays.asList(5, 4, 3, 1, 0);
List<Integer> list2 = Arrays.asList(3, 4, 2, 1, 5);
List<Integer> list3 = Arrays.asList(3, 4, 1, 3, 6);
List<Integer> result = new ArrayList<>();
// you cannot use reslut size because result does not have anything in it, so
// there is no size for result list.
// you can use size each list as long as the size of all the list is the same
for (int i = 0; i < list1.size(); i++) {
result.add(i, list1.get(i) + list2.get(i) + list3.get(i));
}
for (int i = 0; i < result.length; i++) {
System.out.print(result.get(i)+" ");
}
Output:
11 12 6 5 11

multidimensional String[][] array java

I have an array that is from .split command and want to put it into an array called String[][] datatabvars, I do not know how to turn datatabvars into a two dimensional array and put the data into it.
public String[] getList() {
String file_name = "path";
String[] links = null;
String[][] datatabvars = null; // this var
int numberOfDatatabs = 0;
try {
ReadFile file = new ReadFile(file_name);
String[] aryLines = file.OpenFile();
int i;
for(i=0; i < aryLines.length; i++) { //aryLines.length
if (aryLines[i].substring(0, 7).equals("datatab")) {
aryLines[i] = aryLines[i].replace("datatab["+Integer.toString(numberOfDatatabs)+"] = new Array(", "");
aryLines[i] = aryLines[i].replace(");", "");
datatabvars = aryLines[i].split(","); // this split array
numberOfDatatabs++;
}
}
System.out.println(datatabvars[0]);
}catch (IOException e) {
System.out.println( e.getMessage() );
}
return links;
}

Update the two lines(I added comment) as below: (I am assuming that rest of your code is working)
String[][] datatabvars = null; // this var
int numberOfDatatabs = 0;
try {
ReadFile file = new ReadFile(file_name);
String[] aryLines = file.OpenFile();
datatabvars = new String[aryLines.length][]; // INITIALIZED
int i;
for(i=0; i < aryLines.length; i++) { //aryLines.length
if (aryLines[i].substring(0, 7).equals("datatab")) {
aryLines[i] = aryLines[i].
replace("datatab["+Integer.toString(numberOfDatatabs)+"] =
new Array(", "");
aryLines[i] = aryLines[i].replace(");", "");
datatabvars[i] = aryLines[i].split(","); // this split array: ASSIGNED
numberOfDatatabs++;
}
}
System.out.println(datatabvars[0]);

In general, arrays are to avoided like the plague - use collections if possible:. In this case, split() returns a String[], so use that, but use List<String[]> to store multiple String[]:
List<String[]> datatabvars = new ArrayList<String[]>();
...
String[] array = input.split(",");
datatabvars.add(array);
You find life is much easier using collections than arrays.