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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

Display the Shortest Path using BFS in java

This is my BFS algorithm code.
I can calculate the shortest path distance, but somehow I am not able to display the shortest path.
Like for example, I calculated the shortest path from source to destination is 2. But i would like to also display the pathway. (PlaceA -> PlaceB -> PlaceC) for example.
May i know how do i display out the shortest path out using Java?
Please do help me! Thank you!
public static void main(String[] args) {
// TODO Auto-generated method stub
chooseNumOfVertices();
chooseNumOfEdges();
generateGraph();
in.close();
}
private static void generateGraph() {
int source = 0;
int destination = 0;
int edge = chooseEdge;
// TODO Auto-generated method stub
ArrayList<LinkedList<Integer>> graph = new ArrayList<LinkedList<Integer>>();
for (int i = 0; i < limit; i++) {
LinkedList<Integer> vertex = new LinkedList<Integer>();
vertex.add(i);
graph.add(vertex);
}
while (chooseEdge > 0) {
// Randomize the value
int value = new Random().nextInt(cityMapping.size());
int value2 = new Random().nextInt(cityMapping.size());
//
if (value != value2 && !graph.get(value).contains(value2) && !graph.get(value2).contains(value)) {
graph.get(value).add(value2);
graph.get(value2).add(value);
chooseEdge--;
}
}
// Printing out the Nodes
for (int i = 0; i < graph.size(); i++) {
// Return each LinkedList nodes
// System.out.println(graph.get(i));
for (int j = 0; j < graph.get(i).size(); j++) {
// Return each individual nodes inside LinkedList
for (Entry<Integer, String> entry : cityMapping.entrySet()) {
if (entry.getKey() == graph.get(i).get(j)) {
//System.out.print(graph.get(i).get(j) + "-> ");
System.out.print(graph.get(i).get(j) + ". " + entry.getValue() + " -> ");
}
}
}
System.out.println();
}
do {
for (
int i = 0; i < limit; i++) {
int[] newArray = new int[limit];
distance.add(newArray);
predecessor.add(newArray);
}
long time = System.nanoTime();
System.out.println("Searching BFS");
System.out.println("--------------------------------------------");
for (int i = 0; i < limit; i++) {
BFS(graph, i);
}
long CPUTime = (System.nanoTime() - time);
System.out.println("CPU Time for BFS for " + limit + "vertices and " + edge + "edges (in ns): " + CPUTime);
System.out.print("Enter -1 to exit! Enter source vertex (between 0 to " + (limit - 1) + ") : ");
source = in.nextInt();
if (source == -1) {
System.out.print("System terminating...");
break;
}
System.out.print("Enter destination vertex (between 0 to " + (limit - 1) + ") : ");
destination = in.nextInt();
System.out.println("Distance from " + source + " to " + destination + " is: " +
getDistance(source, destination));
System.out.println("The Predecessor of the path from " + source + " to " + destination + " is: "
+ getPredecessor(source, destination));
} while (source != -1);
}
private static void BFS(ArrayList<LinkedList<Integer>> graph, int i) {
// TODO Auto-generated method stub
boolean[] mark = new boolean[graph.size()];
Queue<Integer> L = new ArrayBlockingQueue<Integer>(graph.size()); //Queue
L.add(i);
mark[i] = true;
Arrays.fill(predecessor.get(i), -1);
Arrays.fill(distance.get(i), -1);
distance.get(i)[i] = 0;
while (!L.isEmpty()) {
int vertex = L.remove();
for (int i1 = 0; i1 < graph.get(vertex).size(); i1++) {
int v = graph.get(vertex).get(i1);
if (!mark[v]) {
mark[v] = true;
predecessor.get(i)[v] = vertex;
L.add(v);
distance.get(i)[v] = distance.get(i)[predecessor.get(i)[v]] + 1;
}
}
}
}
public static int getDistance(int start, int end) {
return (distance.get(start)[end]);
}
public static int getPredecessor(int start, int end) {
return (predecessor.get(start)[end]);
}
private static void chooseNumOfEdges() {
System.out.println("Please input the number of Edges:");
chooseEdge = in.nextInt();
}
// Number of Vertices
private static void chooseNumOfVertices() {
in = new Scanner(System.in);
System.out.println("Please input the number of Vertices:");
limit = in.nextInt();
// Read CSV
List<String[]> content = readCsvFile();
// Map each number to a city name
cityMapping = new HashMap<>();
for (int i = 0; i < limit; i++) {
cityMapping.put(i, content.get(i)[0]);
}
// System.out.println(cityMapping);
}
// Read CSV file
public static List<String[]> readCsvFile() {
String csvFile = "./Lab 4/country.csv";
BufferedReader br = null;
ArrayList<String> names = new ArrayList<String>();
List<String[]> content = new ArrayList<>();
String cvsSplitBy = ",";
try {
String line = "";
br = new BufferedReader(new FileReader(csvFile));
while ((line = br.readLine()) != null) {
content.add(line.split(cvsSplitBy));
}
} catch (Exception e) {
e.printStackTrace();
}
Random r = new Random();
Collections.shuffle(content);
return content;
}
}

Reading & Breaking CSV File in Java:

I am editing this question to be more specific and I've learned some Jave to find the solution to my problem. I have a file in CSV format like this:
or in excel like this:
Now I am using Java program to read the second line of file and separate each Comma Separated Value and write it to console as well as on other output file and it was done easily. Now I'm trying to break the last value of:
S/1,M/1,L/1,XL/1 | 2XL/1,3XL/1,4XL/1,5XL/1 | MT/1,LT/1 (Original)
S/1,M/1,L/1,XL/1,2XL/1,3XL/1,4XL/1,5XL/1,MT/1,LT/1 (Modified using program to remove spaces and replacing the Pipes (|) with comma.
In each value, There is the size name before Forward Slash (/) and its quantity is after that. What I'm trying is using the Forward Slash (/) to separate the size with its quantity. And the problem is that the size may contain the forward slash as well (e.g. 12/BT or 2BT/2x). I've tried many algorithms like reversing the whole array or storing the slash count but not getting the success. The whole code to read file and break the comma separated values into separate columns of file is as following:
import java.io.*;
import javax.swing.*;
public class ReadFile3c{
public static void main(String args[]){
try{
//Getting File Name
String fileName = JOptionPane.showInputDialog("Enter File Name") + ".csv";
//Creating Stream with File
FileReader fr = new FileReader(fileName);
//Applying Buffer Filter
BufferedReader br = new BufferedReader(fr);
//Reading First line then Second Line
String s = br.readLine();
s = br.readLine();
s = s + ",";//adding comma at the end of the file
s = s.replaceAll("\\s",""); //Eliminating Spaces
s = s.replaceAll("\\|",","); //Replacing Pipes with comma
char charArray[] = s.toCharArray();
//Declaring Strings and variablse for value separating function
int n = 0; //Array Variable
int m = 0; //Array Variable
String[] inverted = new String[3]; //String to store inverted Commas Values
String[] comma = new String[10]; //String to store comma Values
String value = ""; //Storing character values
try{
//Loop to cycle each character of file
for(int j = 0; j<charArray.length;j++){
//Inverted comma value separator
if (charArray[j] == '"') {
j++;
//loop to gather values b/w invreted comma
while((charArray[j] != '"')){
value = value + charArray[j];
j++;
}
inverted[n] = value;
n++;
j++;
value = "";
}else{
j = j - 1;
//comma Value separator
if (charArray[j] == ','){
j++;
//loop to gether values b/w commas
while((charArray[j] !=',')){
value = value + charArray[j];
j++;
}
comma[m] = value;
m++;
value = "";
}
}
}
}catch(Exception ex){
System.out.println("in inner Exception Block" + ex);
}
//declaring variables to storing values
String name, patternCode, placeSizeQty,width,length,utill,pArea,pPerimeter,totalPcs,placePcs,tSizes;
name = inverted[0];
patternCode = inverted[1];
placeSizeQty = inverted[2];
width = comma[0];
length = comma[1];
utill = comma[2];
pArea = comma[3];
pPerimeter = comma[4];
totalPcs = comma[5];
placePcs = comma[6];
tSizes = comma[7];
//printing all values on Console
System.out.println("\nMarkerName: " + name);
System.out.println("Width :" + width);
System.out.println("Length :" + length);
System.out.println("Utill :" + utill);
System.out.println("Place Area :" + pArea);
System.out.println("Place Perimeter :" + pPerimeter);
System.out.println("PatternCode: " + patternCode);
System.out.println("PlaceSizeQty: " + placeSizeQty);
System.out.println("Total Pcs :" + totalPcs);
System.out.println("Place Pcs :" + placePcs);
System.out.println("Total Sizes :" + tSizes);
//Creating Output file
String fileOutput = JOptionPane.showInputDialog("Enter Output File Name") + ".txt";
//File Writer
try{
//Creating Stream with output file
FileWriter fw = new FileWriter(fileOutput);
//Applying Buffring Stream
PrintWriter pw = new PrintWriter(fw);
//Declaration
String outputLine = null;
//Writing Inverted inputs
for (int u = 0; u <=2 ;u++ ) {
outputLine = inverted[u];
pw.println(outputLine);
System.out.println("Writing: " + outputLine);
}//end of for
//writing comma inputs
for (int t = 0;t <=7 ; t++ ) {
outputLine = comma[t];
pw.println(outputLine);
System.out.println("Writing: " + outputLine);
}//end of for
pw.flush();
pw.close();
fw.close();
fr.close();
br.close();
}catch(Exception ex){
System.out.println("Output: " + ex);
}//End of output catch
}catch(IOException ex){
System.out.println(ex);
}//end of catch
}//end of catch
}//end of Class
And the code to Break the Size and quantity and store it in Double array (Not completed) is as Following:
import java.io.*;
import javax.swing.*;
public class ReadFileInvert{
public static void main(String args[]){
try{
String fileName = JOptionPane.showInputDialog("Enter File Name") + ".csv";
FileReader fr = new FileReader(fileName);
BufferedReader br = new BufferedReader(fr);
String s = br.readLine();
System.out.println(s);
s = s.replaceAll("\\s","");
s = s.replaceAll("\\|",",");
System.out.println(s);
char charArray[] = s.toCharArray();
char charArrayI[] = new char[charArray.length + 1];
int j = 0;
String value = "";
for(int i = charArray.length; i > 0; i--){
charArrayI[j] = charArray[i];
value = value + charArrayI[j];
j++;
}
System.out.println("1" + value);
}catch(Exception ex){
System.out.println(ex);
}
}
}
Now in simple I just want to Separate the sizes (Which may contains the Forward Slashes) with its quantity (After last slash of each value) and store it in double array Like charArray[sizeName][Qty]. Sorry if i didn't explained my problem well as I'm Learning the Coding. but I'll provide as much info as you want.

Have you considered looking at the CAD software export to see if there is a solution on the file creation side? Or is this file coming from a third party?

OK. So, after the hard work of whole day, I've found the following solution to my problem:
import java.io.*;
import javax.swing.*;
public class ReadFileInvert2{
public static void main(String args[]){
try{
String fileName = JOptionPane.showInputDialog("Enter File Name") + ".csv";
FileReader fr = new FileReader(fileName);
BufferedReader br = new BufferedReader(fr);
String s = br.readLine();
System.out.println(s);
s = s.replaceAll("\\s","");
s = s.replaceAll("\\|",",");
System.out.println(s);
char charArray[] = s.toCharArray();
int x = charArray.length - 1;
charArray[x] = ',';
int no = 1;
int size = 1;
int qty = 2;
String sizeS = "";
String qtyS = "";
//String resSet[][] = new String[4][2];
String resSize[] = new String[20];
String resQty[] = new String[20];
int slashNo = 0;
String value = "";
for (int j = 1; j < charArray.length; j++){
int n = j;
if (charArray[j] == ','){
j++;
}
while (charArray[j] != ','){
if (charArray[j] == '/') {
slashNo = j;
//j++;
}
value = value + charArray[j];
//System.out.println(value);
j++;
}
for (int k = n;k < slashNo; k++ ) {
sizeS = sizeS + charArray[k];
//System.out.println(sizeS);
}
for (int l = slashNo + 1; l < j; l++ ) {
qtyS = qtyS + charArray[l];
//System.out.println(qtyS);
}
resSize[no] = sizeS;
System.out.println(resSize[no]);
resQty[no] = qtyS;
System.out.println(resQty[no]);
System.out.println("Size is: " + resSize[no] + ", and Qty is: " + resQty[no]);
no++;
slashNo = 0;
sizeS = "";
qtyS = "";
}
String fileOutput = JOptionPane.showInputDialog("Enter Output File Name: ") + ".txt";
try{
FileWriter fw = new FileWriter(fileOutput);
PrintWriter pw = new PrintWriter(fw);
String outputSize = null;
String outputQty = null;
for (int t = 1; t < no; t++) {
outputSize = resSize[t];
outputQty = resQty[t];
pw.println(outputSize + " = " + outputQty);
System.out.println("Writing: "+ outputSize + " = " + outputQty);
}
pw.flush();
pw.close();
fw.close();
fr.close();
br.close();
}catch(Exception ex){
System.out.println("Output " + ex);
}
}catch(Exception ex){
System.out.println(ex);
}
}
}
Now its in Generic form but will improve it later. But still its working fine. Thanks for your Help stack overflow Community.

My array Printing NULL

In the method, i have all these initialize
Scanner input = new Scanner(System.in);
File file = new File("order.dat");
File viewOrder = new File("ViewOrder.dat");
String orderNo, itemNo, itemNameHolder, qtyHolder, priceHolder, status;
int hold, count = 0, countArray = 0;
double tempPriceHolder, totalPrice = 0;
String tempStatus = "";
String[] holdItemNo = null;
String[] holdName = null;
Integer[] holdQty = null;
Double[] holdTotal = null;
String[] holdStatus = null;
After, i try to read all my content in the file and store the content into holdX array
try {
BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
String line = null;
while ((line = br.readLine()) != null) {
String tokens[] = line.split(";");
orderNo = tokens[0];
itemNo = tokens[1];
itemNameHolder = tokens[2];
qtyHolder = tokens[3];
priceHolder = tokens[4];
status = tokens[5];
if (orderNo.equalsIgnoreCase(userOrderNo)) {
tempPriceHolder = Double.parseDouble(priceHolder);
hold = Integer.parseInt(qtyHolder);
tempPriceHolder = tempPriceHolder * hold;
totalPrice += tempPriceHolder;
countArray++;
holdItemNo = new String[countArray];
holdName = new String[countArray];
holdQty = new Integer[countArray];
holdTotal = new Double[countArray];
holdStatus = new String[countArray];
if (status.matches("s")) {
tempStatus = "Success";
} else if (status.matches("p")) {
tempStatus = "Partially Full";
} else if (status.matches("o")) {
tempStatus = "Out of Stock";
}
holdItemNo[count] = itemNo;
holdName[count] = itemNameHolder;
holdQty[count] = hold;
holdTotal[count] = tempPriceHolder;
holdStatus[count] = tempStatus;
count++;
}
}
} catch (Exception e) {
System.out.println("Error");
}
Final, i write all my array into a new file.
System.out.printf("%s %15s %15s %10s %10s\n", "Item No", "Description", "Quantity", "Total", "Status");
for (int i = 0; i < holdItemNo.length; i++) {
System.out.printf("\n%-11s %-18s %-13s $%-8s %s \n", holdItemNo[i], holdName[i], holdQty[i], holdTotal[i], holdStatus[i]);
}
System.out.println("-----------------------------------------------------------------------");
System.out.printf("%46s %s\n", "$", totalPrice);
System.out.print("Print Order to file Y/N: ");
String choice = input.next();
if (choice.equalsIgnoreCase("y")) {
try {
PrintWriter bw = new PrintWriter(new FileWriter("ViewOrder.dat", true));
for (int i = 0; i < holdItemNo.length; i++) {
bw.write(userOrderNo + ";" + holdItemNo[i] + ";" + holdName[i] + ";" + holdQty[i] + ";" + holdTotal[i] + ";" + holdStatus[i] + "\n");
bw.flush();
}
bw.flush();
bw.close();
System.out.println("Sucessfull!");
} catch (Exception e) {
System.out.println("Error");
}
} else if (choice.equalsIgnoreCase("n")) {
System.out.println("");
}
but the problem is even my code is working but the output is not what i expected. It printed out the printed out the last content and also the sub price is working as well but the rest is only printed out NULL.
Example
Also, it gave me warning of Derefencing possible null pointer on the array.length
for (int i = 0; i < holdItemNo.length; i++) {
bw.write(userOrderNo + ";" + holdItemNo[i] + ";" + holdName[i] + ";" + holdQty[i] + ";" + holdTotal[i] + ";" + holdStatus[i] + "\n");
bw.flush();
}

Guessing:
holdItemNo = new String[countArray];
and the following lines: you are creating these new array objects within your reading loop (inside a condition).
So probably that condition never goes true; therefore your arrays stay all null. But even when the condition is met - you probably expect that to happen more then once. And guess what: you are creating completely new arrays then. While throwing away the previously created array. Each time the if condition turns true you will lose previously stored values!
So the answer is: create your arrays before entering the loop. This means that you either have to query "how many slots to create" upfront; or you have to create an array with say 100 empty slots; and within your loop you then have to check if you still have free slots.
Or you start using java.util.List resp. ArrayList - which allows for dynamic adding of elements.

running time error when trying to implent a keyword frequency counter in my parser java

I want to implement my input reading method into my main class, I want use my code to parse. It's been fixed now. thanks.
String x;
int count = -1;=
while (str.hasMoreTokens()) {
count++;
x = str.nextToken();
word[count] = x;
System.out.println(count + ": " + word[count]);
}
System.out.println("---Frequency---");
// create unique words
for (int i = 0; i < 7; i++) {
if ((!Arrays.asList(unique).contains(word[i]))) {
unique[i] = word[i];
}
}
// measuring frequency
int[] measure = new int[10];
for (int a = 0; a < 7; a++) {
if (Arrays.asList(unique).contains(word[a])) {
measure[a] += 1;
System.out.println(unique[a] + " : " + measure[a]);
}
}
}
}
private List<String[]> termsDocsArray = new ArrayList<String[]>();
private List<String> allTerms = new ArrayList<String>(); //to hold all terms
private List<double[]> tfidfDocsVector = new ArrayList<double[]>();
/**

To start with your code
String text = "Professor, engineering, data, mining, research";
StringTokenizer str = new StringTokenizer(text);
String word[] = new String[10];
String unique[] = new String[10];
String x;
int count = -1;
while (str.hasMoreTokens()) {
count++;
x = str.nextToken();
word[count] = x;
System.out.println(count + ": " + word[count]);
}
System.out.println("---Frequency---");
// create unique words
for (int i = 0; i < 7; i++) {
if ((!Arrays.asList(unique).contains(word[i]))) {
unique[i] = word[i];
}
}
// measuring frequency
int[] measure = new int[10];
for (int a = 0; a < 7; a++) {
if (Arrays.asList(unique).contains(word[a])) {
measure[a] += 1;
System.out.println(unique[a] + " : " + measure[a]);
}
}
should be in it's own method like .
private void doSomething(){
//This variable will hold all terms of each document in an array.
String text = "Professor, engineering, data, mining, research";
StringTokenizer str = new StringTokenizer(text);
String word[] = new String[10];
String unique[] = new String[10];
String x;
int count = -1;
while (str.hasMoreTokens()) {
count++;
x = str.nextToken();
word[count] = x;
System.out.println(count + ": " + word[count]);
}
System.out.println("---Frequency---");
// create unique words
for (int i = 0; i < 7; i++) {
if ((!Arrays.asList(unique).contains(word[i]))) {
unique[i] = word[i];
}
}
// measuring frequency
int[] measure = new int[10];
for (int a = 0; a < 7; a++) {
if (Arrays.asList(unique).contains(word[a])) {
measure[a] += 1;
System.out.println(unique[a] + " : " + measure[a]);
}
}
}
Secondly in ur given code u have written like
int count = -1;=
which accounts to this error Syntax error on token "=", { expected.It should be
int count = -1;
And since all your code is simply written in class without any method so it is giving you the error saying { expected.
Please make sure you have copied the code correctly.