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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);
}

Use custom class in HashMap in android

EDIT: I have posted it earlier for java. But it working in Java but not in android. So I am posting the android code now.
I am trying to use a custom class into a HashMap in my android application. But it is not giving my desired output. Please help.
I want to do something like this...
//Code for android application:
//Point class
class Point{
private int x;
private int y;
public Point(){
}
public Point(int _x, int _y){
this.x = _x;
this.y = _y;
}
}
DataManager.java
public class DataManager {
private Vector<Integer> RSSI = null;
private int numOfRSSI;
private Map<Vector<Integer>, Point> SingleData = null;
private Vector<Map<Vector<Integer>, Point>> Data = null;
private Context context;
public DataManager(Context _context) {
this.context = _context;
Data = new Vector<Map<Vector<Integer>, Point>>();
}
public void loadData(String filename) {
if (Data == null) {
System.out.println("***ERROR: DataSet not initalized!!!\n");
}
readFile(filename);
}
public void printData(){
Vector<Integer> rssi = null;
Map<Vector<Integer>, Point> single = null;
Point point = null;
for(int i=0;i<Data.size();i++){
single = new HashMap<Vector<Integer>, Point>() ;
single = Data.get(0);
for (Map.Entry<Vector<Integer>, Point> entry :single.entrySet()) {
rssi = new Vector<Integer>();
point = new Point();
rssi = entry.getKey();
point = entry.getValue();
System.out.print("("+point.x+" "+point.y+") ");
for(int j = 0;j<rssi.size(); j++){
System.out.print(rssi.get(j)+" ");
}
System.out.println("");
}
}
}
private void readFile(String filename) {
InputStream is = null;
try {
is = context.getResources().getAssets().open("datasets.txt");
} catch (IOException e) {
e.printStackTrace();
System.out.println("error file reading");
}
if (is != null) {
StringBuilder text = new StringBuilder();
int flag = 0;
try {
BufferedReader br = new BufferedReader(
new InputStreamReader(is));
String line;
while ((line = br.readLine()) != null) {
if(flag==0){
flag=1;
this.numOfRSSI = Integer.parseInt(line);
System.out.println("number of RSSI: "+numOfRSSI);
}
else if(flag==1){
parseLine(line);
}
}
} catch (IOException e) {
// Error reading file
}
finally {
// myHelper.print(text.toString());
}
}
}
private void parseLine(String line) {
RSSI = new Vector<Integer>();
SingleData = new HashMap<Vector<Integer>, Point>();
StringTokenizer st = new StringTokenizer(line, ",");
int co = 0;
int x=0,y=0;
while (st.hasMoreTokens()) {
if(co < this.numOfRSSI){
RSSI.add(Integer.parseInt(st.nextToken()));
co++;
}
else{
x = Integer.parseInt(st.nextToken());
y = Integer.parseInt(st.nextToken());
}
}
Point point = new Point(x,y);
SingleData.put(RSSI, point);
Data.add(SingleData);
}
}
MainActivity.java
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
DataManager dataManager = new DataManager(MainActivity.this);
dataManager.loadData("datasets.txt");
dataManager.printData();
}
}
datasets.txt
5
-61,-51,-46,-41,-28,1,0
-60,-50,-51,-47,-34,2,0
-72,-52,-53,-55,-37,3,0
-60,-44,-58,-53,-40,3,1
-68,-55,-46,-47,-45,2,1
-66,-60,-48,-43,-37,1,1
-62,-57,-49,-45,-34,0,2
Output is showing.....
1 0 -61 -51 -46 -41-28
1 0 -60 -50 -51 -47 -34
1 0 -72 -52 -53 -55 -37
etc.....
But it should be...
1 0 -61 -51 -46 -41-28
2 0 -60 -50 -51 -47 -34
etc...
So this is my problem.

Below is working fine on my machine :-
import java.util.Map;
import java.util.Vector;
public class Demo {
public static void main(String[] args) {
Map<Vector<Integer>, Point> vectorPointMap = new HashMap<Vector<Integer>, Point>();
Vector<Integer> vector1 = new Vector<Integer>();
vector1.add(1);
vector1.add(2);
vector1.add(3);
vectorPointMap.put(vector1, new Point(10, 10));
Vector<Integer> vector2 = new Vector<Integer>();
vector2.add(4);
vector2.add(5);
vector2.add(6);
vectorPointMap.put(vector2, new Point(20, 20));
// Print data
for (Map.Entry<Vector<Integer>, Point> entry : vectorPointMap.entrySet()) {
Vector<Integer> keyVector = entry.getKey();
Point valuePoint = entry.getValue();
System.out.print("(" + valuePoint.x + " " + valuePoint.y + ") ");
for (int j = 0; j < keyVector.size(); j++) {
System.out.print(keyVector.get(j) + " ");
}
System.out.println("");
}
}
}

You should change this from
for(int i=0;i<Data.size();i++){
single = new HashMap<Vector<Integer>, Point>() ;
single = Data.get(0);
}
to
for(int i=0;i<Data.size();i++){
single = new HashMap<Vector<Integer>, Point>() ;
single = Data.get(i);
}

try changing:
single = Data.get(0);
to
single = Data.get(i);

What does it mean, "it does not give right"?
You can put your own classes to Map, there is no problem. But remember, when you put items to HashMap in some order, there is no guarantee, it will come out in the same order. If you need to have same order on output, as on input, instead HashMap use LinkedHashMap. You can use it in the same way as HashMap, but it preserves order of inserted items.

Code to read the dataset

Here I read the dataset and extracted the data lines(not the attributes) and print it.Next I need to sort the dataset.Now this is stored in an ArrayList.How to sort it?
public static void main(String args[]) throws Exception
{
String filen, jsnfl;
Customiseddata data = new Customiseddata();
data.setAlgorithm("C4.5");
data.setUserName("Dahlia");
System.out.println("Enter the file name");
sc = new Scanner(System.in);
filen = sc.nextLine();
data.setFileName("input_files/" + filen);
Mainclass main = new Mainclass();
main.build(data);
}
public void build(Customiseddata data) throws Exception
{
int extension;
String filename;
filename = data.getFileName();
extension = filename.lastIndexOf('.');
String extensionType = filename.substring(extension + 1,
filename.length());
if (extensionType.equalsIgnoreCase("csv"))
{
readcsv(filename);
}
else if (extensionType.equalsIgnoreCase("arff"))
{
readarff(filename);
}
}
public void readarff(String filename) throws Exception
{
#SuppressWarnings("unused")
int filesize, attributesize, c = 0, i;
#SuppressWarnings("unused")
float v = 0;
String s, line1;
ArrayList<String> filelines;
ArrayList<String> attributes;
Customiseddata data = new Customiseddata();
Arfffilereader arfffile = new Arfffilereader();
Extractdata exdata = new Extractdata();
exdata = arfffile.extractInputArff(filename);
filelines = exdata.getFileLines();
attributes = exdata.getAttributes();
filesize = filelines.size();
attributesize = attributes.size();
data.setFilesize(filesize);
System.out.println("Print the attributes");
System.out.println("--------------------");
for (i = 0; i < attributesize; i++)
{
System.out.println(attributes.get(i));
}
System.out.println("\t");
System.out.println("Print the filelines");
System.out.println("--------------------");
for (int j = 0; j < filesize; j++)
{
System.out.println(filelines.get(j));
}
}
But after this I need to sort the dataset.

Since the elements of the list are Strings and since String implements Comparable, sorting a list is as simple as:
Collections.sort(theList);
Note however that it will sort the list in place. If you don't want that, make a copy of the list and sort that copy.