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Not able to print out the Array Elements

This code is to get the firstName, LastName, and StudentID by reading it from a file and displaying the information in the main file. When I run my program, instead of printing the information of the students, it prints out a chain of characters and numbers.
public class main {
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
Student[] students = new Student[10];
getStudentData(students);
for (int i = 0; i < students.length; i++){
System.out.println(students[i]);
}
}
public static void getStudentData(Student[] students){
String infileName = "studentlist.txt";
Scanner reader = null;
try {
reader = new Scanner (new File(infileName));
int index = 0;
while(reader.hasNext()){
String oneLine = reader.nextLine();
String[] parts = oneLine.split(" ");
long studentID = Long.parseLong(parts[2]);
students[index] = new Student(parts[0],parts[1],studentID);
index++;
}
} catch (FileNotFoundException err) {
System.out.println(err);
} finally {
if (reader != null)
reader.close();
}
}
}

Have you defined a toString() method on your Student class?
You need to do this otherwise the default toString() implementation of the superclass for all classes (class Object) will be used which returns the name of the class concatenated with # and the hashcode of the class in hexadecimal format.
Add this method to your Student class and return a meaningful String containing the attribute values of a Student object instead of my descriptive String.
#Override
public String toString() {
return "return a string here that represents the student and his/ her attribute values";
}
FYI: Many IDEs can generate an arbitrary toString() method for you.
See the this thread for more details on Object::toString().

Arrays of Object test but not getting any output

I would like some guidance on this particular code that I am testing but currently it is not printing out anything and on top of that I feel as if it isn't reading the text file at all. It seems to finish right away with no errors and I only get prompted that "build is successful."
The assignment is to read from a data text file that list 20 lines of student information, each line is comprised of first name, last name, and their grade all seperated by spaces. I am put to it into an array and output their information, but for now I am testing to see if it will output the first name before I proceed.
public class studentClass {
private String studentFName, studentLName;
private int testScore;
private char grade;
//constructor
public studentClass(String stuFName, String stuLName, int stuTestScore){
studentFName = stuFName;
studentLName = stuLName;
testScore = stuTestScore;
}
public String getStudentFName(){
return studentFName;
}
public String getStudentLName(){
return studentLName;
}
public int getTestScore(){
return testScore;
}
public char getGrade(){
return grade;
}
public void setStudentFName(String f){
studentFName = f;
}
public void setStudentLName(String l){
studentLName = l;
}
public void setTestScore(int t){
if (t>=0 && t<=100){
testScore = t;
}
}
public void setGrade(char g){
grade = g;
}
}
public static void main(String[] args) throws IOException {
int numberOfLines = 20;
studentClass[] studentObject = new studentClass[numberOfLines];
for(int i = 0; i>studentObject.length; i++){
System.out.print(studentObject[i].getStudentFName());
}
}
public static studentClass[] readStudentData(studentClass[] studentObject)throws IOException{
//create FileReader and BufferedReader to read and store data
FileReader fr = new FileReader("/Volumes/PERS/Data.txt");
BufferedReader br = new BufferedReader (fr);
String lines = null;
int i = 0;
//create array to store data for firstname, lastname, and score
while ((lines = br.readLine()) != null){
String stuArray[] = lines.split(" ");
String stuFName = stuArray[0];
String stuLName = stuArray[1];
int score = Integer.parseInt(stuArray[2]);
studentObject[i] = new studentClass (stuFName, stuLName, score);
i++;
}
return studentObject;
}

You need to actually call the method to read in the data. Try the following (note I didn't handle the Exception. I leave that as an exercise to you)
public static void main(String[] args) throws IOException {
int numberOfLines = 20;
studentClass[] studentObject = new studentClass[numberOfLines];
readStudentData(studentObject);
//NOTE I CHANGED THE '>' TO '<'
for(int i = 0; i < studentObject.length; i++){
System.out.print(studentObject[i].getStudentFName());
}
}
//Note that I changed the return type to void
public static void readStudentData(studentClass[] studentObject)throws IOException{
//Your code here
You'll see I changed your readStudentData to return void since you're passing the array into the method you don't need to return it. You'll need to remove the return at the end of it.
You could also leave it as a method returning a studentClass[] and have no parameters. Instead, create the studentClass array inside readStudentData. I would recommend that approach because it removes the need to create and pass the array, which complicates your main method.

Non-main print method won't work in Java program

I'm trying to get the "Ratings Report" stuff to print out but all that is printing is the mov1.get stuff. Also, any other problems that are in my program would be helpful to be pointed out as well.
public class PopulatePracticec {
static int countG;
static int countPG;
static int countPG13;
static int countR;
public static void main(String[] args) throws FileNotFoundException {
Scanner inFile = new Scanner(new FileReader("D:\\finalData.in"));
Scanner inFile2 = new Scanner(new FileReader("D:\\finalDataCategories.in"));
do {
inFile.nextLine();
String Id = inFile.next();
String title = inFile.next();
String releaseYear = inFile.next();
String runTime = inFile.next();
String rating = inFile.next();
inFile2.nextLine();
String id2 = inFile2.next();
String genre = inFile2.next();
Practicec mov1 = new Practicec();
mov1.setId(Id);
mov1.setTitle(title);
mov1.setReleaseYear(releaseYear);
mov1.setRunTime(runTime);
mov1.setRating(rating);
mov1.setGenre(genre);
System.out.println(mov1.getId());
System.out.println(mov1.getTitle());
System.out.println(mov1.getReleaseYear());
System.out.println(mov1.getRunTime());
System.out.println(mov1.getRating());
System.out.println(mov1.getGenre());
}
while (inFile.hasNext());
inFile.close();
inFile2.close();
}
public static void processRating(String rating) {
switch (rating) {
case "G":
countG++;
break;
case "PG":
countPG++;
break;
case "PG13":
countPG13++;
break;
case "R":
countR++;
break;
}
}
public static int lookG() {
return countG;
}
public static int lookPG() {
return countPG;
}
public static int lookPG13() {
return countPG13;
}
public static int lookR() {
return countR;
}
public static void outputLines(String rating) {
System.out.println("Ratings Report");
System.out.println();
System.out.println("G = " + countG);
System.out.println("PG = " + countPG);
System.out.println("PG13 = " + countPG13);
System.out.println("R = " + countR);
}
}

What they are trying to say is that you are not calling the outputLines method you created. Within your main method, you need to call your outputLines method and pass a string to hold the ratings for the parameter. Once the method is called, it will print the code inside your method. The problem is that you just didn't call the outputLines method, so there's no way it will be displayed.
It should look something like this:
outputLines(String r); // r holds a copy of the values stored in ratings
Also, what you could do is instead of having a method like outputLines, you could create a toString method in which you can pass all the values needed to print the ratings review stuff and return one formatted and concatenated string.
Hope this helped you.

Creating array from reading a file

I have a file with the following:
5
212:Float On:Modest Mouse
259:Cherub Rock:Smashing Pumpkins
512:Won't Get Fooled Again:The Who
417:Teen Age Riot:Sonic Youth
299:PDA:Interpol
I need to create a array but I need to take into account the integer it starts with, then read the rest as strings taking into account the initial line containing only an integer. I've made the method to read the file and print, just don't know how to split it up.

An example of how to do it:
String s = "212:Float On:Modest Mouse"; // your input - a line from the file
String[] arr = s.split(":");
System.out.println(arr[0]); // your int
// The rest of the array elements will be the remaining text.
// You can concatenate them back into one string if necessary.

you can read file using Scanner
readlines = new Scanner(filename);
while(readlines.hasNextLine())
{
String line = readlines.nextLine();
String[] values = line.split(":");
int firstColumn = -1;
if (values.length > 0) {
try {
firstColumn = Integer.parseInt(values[0]);
} catch (NumberFormatException ex) {
// the value in the first column is not an integer
}
}
}

I've grown a habit of reading the entire file into a List, then handling the List in memory. Doing this is not the only option.
Once I have the file read in, I look at the first line to know how many tracks to expect in the remaining file. I then would loop through the remaining List to either get the number of tracks from the first line or until I reach the end of the list, in the event that the number of tracks (from the first line) exceeds the actual amount of tracks that are in the file.
As I go through the tracks I would use substring to break the line apart, and convert just the first part.
Update
Base on your comment, I've updated to use split instead of substring. Then some basic alignment formatting for output
public static void main(String[] args) throws Exception {
String yourFile = "path to your file.txt";
List<String> yourFileLines = new ArrayList<>(Files.readAllLines(Paths.get(yourFile)));
// You know the first line is suppose to be the number of tracks so convert it to a number
int numberOfTracks = Integer.valueOf(yourFileLines.get(0));
// Either go to the number of tracks or till the end of file
List<Track> tracks = new ArrayList<>();
for (int i = 1; (i <= numberOfTracks && i < yourFileLines.size()); i++) {
String currentFileLine = yourFileLines.get(i);
String[] currentFileLinePieces = currentFileLine.split(":");
Track currentTrack = new Track();
currentTrack.TrackTime = Integer.valueOf(currentFileLinePieces[0]);
currentTrack.TrackTitle = currentFileLinePieces[1];
currentTrack.TrackArtist = currentFileLinePieces[2];
tracks.add(currentTrack);
}
System.out.println(String.format("%-20s\t\t%-20s\t\t%-20s", "TITLE", "ARTIST", "TIME"));
System.out.println(String.format("%-20s\t\t%-20s\t\t%-20s", "-----", "------", "----"));
for (Track currentTrack : tracks) {
System.out.println(currentTrack);
}
}
public static class Track {
public int TrackTime;
public String TrackTitle;
public String TrackArtist;
#Override
public String toString() {
return String.format("%-20s\t\t%-20s\t\t%-20d", TrackTitle, TrackArtist, TrackTime);
}
}
Results:
Here's an example using a Scanner, and breaking everything into methods. You should be able to use List and ArrayList. Results are the same.
public static void main(String[] args) throws Exception {
String yourFile = "data.txt";
List<String> yourFileLines = readFile(yourFile);
if (yourFileLines.size() > 0) {
// You know the first line is suppose to be the number of tracks so convert it to a number
int numberOfTracks = Integer.valueOf(yourFileLines.get(0));
List<Track> tracks = getTracks(numberOfTracks, yourFileLines);
printTracks(tracks);
}
}
public static List<String> readFile(String pathToYourFile) {
List<String> yourFileLines = new ArrayList();
try {
File yourFile = new File(pathToYourFile);
Scanner inputFile = new Scanner(yourFile);
while(inputFile.hasNext()) {
yourFileLines.add(inputFile.nextLine().trim());
}
} catch (Exception e) {
System.out.println(e);
}
return yourFileLines;
}
public static List<Track> getTracks(int numberOfTracks, List<String> yourFileLines) {
List<Track> tracks = new ArrayList();
// Either go to the number of tracks or till the end of file
for (int i = 1; (i <= numberOfTracks && i < yourFileLines.size()); i++) {
String currentFileLine = yourFileLines.get(i);
String[] currentFileLinePieces = currentFileLine.split(":");
Track currentTrack = new Track();
currentTrack.TrackTime = Integer.valueOf(currentFileLinePieces[0]);
currentTrack.TrackTitle = currentFileLinePieces[1];
currentTrack.TrackArtist = currentFileLinePieces[2];
tracks.add(currentTrack);
}
return tracks;
}
public static void printTracks(List<Track> tracks) {
System.out.println(String.format("%-20s\t\t%-20s\t\t%-20s", "TITLE", "ARTIST", "TIME"));
System.out.println(String.format("%-20s\t\t%-20s\t\t%-20s", "-----", "------", "----"));
for (Track currentTrack : tracks) {
System.out.println(currentTrack);
}
}
public static class Track {
public int TrackTime;
public String TrackTitle;
public String TrackArtist;
#Override
public String toString() {
return String.format("%-20s\t\t%-20s\t\t%-20d", TrackTitle, TrackArtist, TrackTime);
}
}

Entering multiple things in to one array in java

I am quite new to java but have a project i need to complete and am stuck on a certain part.
I want to allow the user to enter a route including, start destination, an end destination, and a number of stops. I have been able to do this, but then i want the user to have the ability of being able to add the same things again, to the same array. without deleting the existing route
here is the code i have so far
import java.util.Scanner;
import java.util.Arrays;
public class main {
public static void main(String[] args){
menu();
}
public static void menu(){
Scanner scanner = new Scanner(System.in);
System.out.println("enter 1 to input a new route");
int option = scanner.nextInt();
if(option==1){
inputRoute();
}
}
public static void inputRoute(){
Scanner scanner = new Scanner(System.in);
System.out.println("Please Enter Starting Destination");
String startDest = scanner.next();
System.out.println("Please Enter End Destination");
String endDest = scanner.next();
System.out.println("Please Enter Number of stops");
int numberOfStops = scanner.nextInt();
String[] stops = new String[numberOfStops];
for(int i = 1; i<=numberOfStops; i++){
System.out.println("Enter Stop" + i);
stops[i-1] = scanner.next();
}
System.out.println(Arrays.toString(stops));
menu();
}
}
however when this runs, if i go back and enter in another route, it will just delete the existing route.
Is there any way of appending the next route to the end of that array or any way of doing this?
thank you

Like crush said. Rather than use a normal array of strings, use an ArrayList<String> object. Or even an ArrayList<String[]> and stash each individual route in there.

First of all you will need to declare the stops array as an instance variable, otherwise you will always be creating a new array whenever you call the method inputRoute().
and then to preserve old entries i can think of two ways-->
--> modify the loop as below...
for(int i = 1; i<=numberOfStops; i++){
System.out.println("Enter Stop" + i);
if(stops!=null) //without the if condition it will also append null in the start
stops[i-1]=stops[i-1]+", "+ scanner.next(); // you can you any separator
else
stops[i-1]=scanner.next();
}
--> or you can ArrayList or any other Collection that provides auto increment

Try declaring stops as a global variable. (right below the class line)
Also I would recommend using an ArrayList, List something on those lines

You can't use an array for this (without constantly re-allocating them) as Arrays are fixed in size once created.
Use an ArrayList though and you can add as many items as you like whenever you like.

The easy (and slightly wrong) solution would be to make your array a static array that is defined outside any method. That will get you going (although you will have to make the array big enought.
Other recommendations:
Capatilize your Main class--avoids confusiong (even moreso if you
don't call it main!)
Make your public static void main method do
this: new Main()
Then get rid of all the other statics.
Use a collection instead of an array.
instead of adding each entry into the array separately (which will make EVERYTHING harder for you), create a second class with 3 fields (start, end, stop) and each time you input another record, "new" an instance of the second class, place the three things into the new instance and place that instance on your collection.
It may seem arbitrary and unnecessary right at this minute, but if you have ANY follow-on work to do on this class these things will make your life easier. If any seems confusing or you want to understand why, feel free to ask in the comments.

I think this will help you.
Main file.
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;
public class Main {
public static void main(String[] args){
menu();
}
public static void menu(){
List<Route> routeList = new ArrayList<Route>();
Scanner scanner = new Scanner(System.in);
System.out.println("enter 1 to input a new route");
int option = scanner.nextInt();
if(option==1){
routeList.add(inputRoute());
}
System.out.println("Complete list of routes is "+routeList);
}
public static Route inputRoute(){
Route route = new Route();
Scanner scanner = new Scanner(System.in);
System.out.println("Please enter the name of the route");
String name = scanner.next();
route.setName(name);
System.out.println("Please Enter Starting Destination");
String startDest = scanner.next();
route.setStartLocation(startDest);
System.out.println("Please Enter End Destination");
String endDest = scanner.next();
route.setEndLocation(endDest);
System.out.println("Please Enter Number of stops");
int numberOfStops = scanner.nextInt();
if(numberOfStops > 0){
route.setStopList(new ArrayList<String>());
for(int i = 1; i<=numberOfStops; i++){
System.out.println("Enter Stop" + i);
route.getStopList().add(scanner.next());
}
System.out.println("current entered route is "+route);
menu();
}
return route;
}
}
Route file:
import java.util.List;
public class Route {
String name ;
String startLocation;
String endLocation;
List<String> stopList;
public Route() {
}
public Route(String name, String startLocation, String endLocation, List<String> stopList) {
this.name = name;
this.startLocation = startLocation;
this.endLocation = endLocation;
this.stopList = stopList;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getStartLocation() {
return startLocation;
}
public void setStartLocation(String startLocation) {
this.startLocation = startLocation;
}
public String getEndLocation() {
return endLocation;
}
public void setEndLocation(String endLocation) {
this.endLocation = endLocation;
}
public List<String> getStopList() {
return stopList;
}
public void setStopList(List<String> stopList) {
this.stopList = stopList;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Route route = (Route) o;
if (endLocation != null ? !endLocation.equals(route.endLocation) : route.endLocation != null) return false;
if (name != null ? !name.equals(route.name) : route.name != null) return false;
if (startLocation != null ? !startLocation.equals(route.startLocation) : route.startLocation != null)
return false;
if (stopList != null ? !stopList.equals(route.stopList) : route.stopList != null) return false;
return true;
}
#Override
public int hashCode() {
int result = name != null ? name.hashCode() : 0;
result = 31 * result + (startLocation != null ? startLocation.hashCode() : 0);
result = 31 * result + (endLocation != null ? endLocation.hashCode() : 0);
result = 31 * result + (stopList != null ? stopList.hashCode() : 0);
return result;
}
#Override
public String toString() {
return "Route{" +
"name='" + name + '\'' +
", startLocation='" + startLocation + '\'' +
", endLocation='" + endLocation + '\'' +
", stopList=" + stopList +
'}';
}
}