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Java: Why does my toString method print wrong information?

I have an abstract superclass that has two attributes: int and string. I have overridden the toString method in it as well as in its subclass that has one extra attribute (LocalDate). However, for some reason that I don't understand, when I print the subclass toSring info, the int value changes.
This is what I have in the superclass:
public abstract class File {
private int id;
private String text;
public File(int newId, String newText) throws IllegalArgumentException {
id(newId);
text(newText);
}
public int id() {
return id;
}
public void id(int e) throws IllegalArgumentException {
if (e <= 0) {
throw new IllegalArgumentException();
}
else {
id = e;
}
}
public String text() {
return text;
}
public void text(String aText) throws IllegalArgumentException {
if (aText == null || aText.length() == 0) {
throw new IllegalArgumentException();
}
else {
text = aText;
}
}
#Override
public String toString() {
return '"' + id() + " - " + text() + '"';
}
Then in the subclass I have this:
public class DatedFile extends File {
private LocalDate date;
public DatedFile (int newId, LocalDate newDate, String newText) throws IllegalArgumentException {
super(newId, newText);
date(newDate);
}
public LocalDate date() {
return date;
}
public void date(LocalDate aDate) throws IllegalArgumentException {
if (aDate == null) {
throw new IllegalArgumentException();
}
else {
date = aDate;
}
}
#Override
public String toString() {
return '"' + id() + " - " + date + " - " + text() + '"';
}
I tested it like this:
public static void main(String[] args) {
LocalDate when = LocalDate.of(2020, 1, 1);
DatedFile datedFile1 = new DatedFile(999, when, "Insert text here");
System.out.println(datedFile1);
It printed: "1033 - 2020-01-01 - Insert text here"
However, if i use the following code
System.out.println(datedFile1.id());
it prints the correct id (999). So I assume that something with the toString messes it up, but I have no idea where the problem is.
PS. I'm a beginner and I'm sorry if I included too much code but as I don't know what is the problem, I really don't know what is relevant and what isn't.

Your problem is here:
return '"' + id() + " - " + date + " - " + text() + '"';
id() returns an int, and '"' is a char, which is a numeric type. So '"' + 999 is 1033, not "999.
To fix the problem, use a String instead of a character:
return "\"" + id() + " - " + date + " - " + text() + "\"";

Change your toString() method from '"' to " \"".
'"' is a character (which is stored internally as an Integer), so adding it with id() produces the result you're seeing.

or using string interpolation:
return '\" ${id()} - ${date} - ${text()} \"';

How do I change a Variable, in a Java Class

I have to be able to convert some variables in my class. I have a boolean variable, WaGa (Stands for Workstation/Gaming computer), and if it's true, I want to convert String WorGam
I have to do this through service and support methods, and I keep trying, but I constenly fail. It just prints out what's in the driver. HELP.
public class Graphics
//instance data
{
private int Ram;
private String Brand;
private int Res;
private int BiWi;
private int BaCl;
private boolean K4;
private boolean WaGa;
private String WorGam;
//boolean WaGa, boolean K4, int BaCl, int BiWi, int Res, String Brand, int Ram
public Graphics (int R, String B, int Re, int Bi, int Ba, boolean K4, boolean Wa, String Wor ) // constructor
{
Ram = R;
Brand = B;
Res = Re;
BiWi = Bi;
BaCl = Ba;
K4 = K4;
WaGa = Wa;
Wor = WorGam;
}
public int get_Ram() //Accessor Method - there are 3 of them
{
return Ram;
}
public String get_Brand() //Accessor Method - there are 3 of them
{
return Brand;
}
public int get_Res() //Accessor Method - there are 3 of them
{
return Res;
}
public int get_BiWi() //Accessor Method - there are 3 of them
{
return BiWi;
}
public int get_BaCl()
{
return BaCl;
}
public boolean get_K4()
{
return K4;
}
public String WorGam(boolean WaGa)
{
String WorGam;
if ( WaGa == true) {
return WorGam = "Workstation";
} else {
return WorGam = "True";
}
}
public String toString()
{
return ("Ram" + " " + Ram + ". " + "Brand:" + " " + Brand + ". " + "Resolution" + " " + Res + ". " + "Processer" + " " + BiWi + "." + " " + "Base Clock" + " " + BaCl+ " " + "K4?" + " " + K4+ " " +WorGam);
}
}
public class Graphicse_Driver
{
public static void main(String [] args)
{
Graphics unique=new Graphics(4, "Nvinda", 6, 7, 9, false, false, "sdf" );
System.out.println(unique);

You may need to reread you code to make sure there aren't any other mistakes in your code, but this is the root of your problem.
In order to access the WarGam getter, you need to call:
System.out.println(unique.WarGam());
When you do System.out.println(unique), you are trying to print out the entire Graphics object instead of just the WarGam string.
You then should change your WarGam() method to look like the following:
public String WorGam()
{
if (WaGa) {
return "Workstation";
}
return "Gaming";
}
Here is a more in depth explanation of the changes:
WaGa is a private variable of your Graphics class. Since the WarGam() method is in the same Graphics class, it already had access to the WaGa variable, so you do not need to pass it in.
if(WaGa == true) is just a wordier way of writing if(WaGa).
Instead of creating a String WorGam variable, you can just return the string you want directly.
The else surrounding the second return is unnessary since that code will only be hit if the first return is skipped.
After these changes, the private String WarGam variable is really not necessary either.

public String worGam(boolean waGa) {
if (waGa)
return "Workstation";
else
return "Gaming";
}

You need to correct your worGam() function:
public String worGam(boolean waGa) {
if (waGa == true)
return "Workstation";
else
return "True";
}
And the main() function:
public static void main(String [] args) {
Graphics unique = new Graphics(4, "Nnn", 6, 7, 9, false, false, "xxx");
System.out.println(unique.WorGam(false));
}

How to compare parameter values of two objects in Java?

Right now I'm working on a method for comparing the scores of athletes in the olympics. So far I've had little trouble, however now I've reached a point where i need to compare two objects (athletes) scores and I'm not sure how to do it. This is my code for the Olympic class:
// A program using the Athlete class
public class Olympics {
public static void main(String args[]) {
System.out.println("The leader is " + Athlete.leader() +
", with a score of " + Athlete.leadingScore());
Athlete meryl = new Athlete("Meryl Davis", "U.S.");
meryl.addScore(75);
System.out.println(meryl);
Athlete tessa = new Athlete("Tessa Virtue", "Canada");
System.out.println(tessa);
System.out.println(); // blank line
tessa.addScore(50);
System.out.println(tessa);
System.out.println(meryl);
System.out.println("The leader is " + Athlete.leader() +
", with a score of " + Athlete.leadingScore());
System.out.println(); // blank line
tessa.addScore(100);
meryl.addScore(65);
System.out.println(tessa);
System.out.println(meryl);
System.out.println("The leader is " + Athlete.leader() +
", with a score of " + Athlete.leadingScore());
System.out.println(); // blank line
tessa.addScore(20);
System.out.println("Tessa's final score is " + tessa.getScore());
meryl.move("France");
System.out.println(meryl);
} // end main
} // end class Olympics
And this is the constructor class "Athlete":
public class Athlete {
private String name;
private String country;
protected int score;
public static int leadScore;
public Athlete(String athName, String athCountry) {
this.name = athName;
this.country = athCountry;
score = 0;
if (score < 1) {
System.out.println("Score cannot be lower than 1");
}
}
public int addScore(int athScore) {
score += athScore;
return score;
}
public static String leader(){
//TODO
}
public static int leadingScore() {
//MUST COMPARE BOTH ATHLETES
}
public int getScore(){
return score;
}
public void move(String newCountry) {
country = newCountry;
}
public String toString() {
return name + ": " + "from " + country + ", current score " + score;
}
}
So what I'm trying to do is have the program check Meryl's score compared to Tessa's and return that Athlete's score in leadingScore() and, using that athlete, return a leader(). Any help is appreciated! Thanks.

The function must take the two Athletes you're comparing as the parameters for this to work
public static int leadingScore(Athlete a1, Athlete a2) {
if (a1.getScore() < a2.getScore()) {
// do stuff
}
}

The lead score should not be in the athlete class, but rather in main () because one instance of an Athlete class would not know of other instances unless you put a self-referential list inside the class. Similarly, leadingScore should be in main ().
It or main can call each athlete and compare:
int merylScore = meryl.getScore ();
int tessaScore = tessa.getScore ();
int leadingScore = 0;
String leaderName = "";
if (merylScore > tessaScore) {
leadingScore = merylScore;
leaderName = meryl.getName ();
} else if (tessaScore > merylScore) {
leadingScore = tessaScore;
leaderName = tessa.getName ();
} else {
leadingScore = merylScore;
leaderName = "a tie between Meryl and Tessa";
}
System.out.println ("The leader is " + leaderName + ", with a score of " + leadingScore);

You should consider using a "collection". Use an array, a list ... or even a sorted list.
Stored your individual objects in the collection, then traverse the collection to find the highest score.
For example:
// Create athlete objects; add each to list
ArrayList<Athlete> athletes = new ArrayList<Athlete>();
Athlete meryl = new Athlete("Meryl Davis", "U.S.");
meryl.addScore(75);
...
athletes.add(meryl);
Athlete tessa = new Athlete("Tessa Virtue", "Canada");
...
athletes.add(tessa );
// Go through the list and find the high scorer
Athlete highScorer = ...;
for (Athlete a : athletes) {
if (highScorer.getScore() < a.getScore())
highScorer = a;
...
}
System.out.println("High score=" + highScorer.getScore());
Here's a good tutorial:
http://www.vogella.com/tutorials/JavaCollections/article.html

Java: Unexpected behaviour with concatenating a String and an expression using the plus + operator

Consider the following piece of code
public class Test {
public static void main(String... strings) {
System.out.println("String, " + false);
System.out.println("String, " + getFalse());
System.out.println("String, " + new TestClass());
System.out.println("String, " + (new TestClass() == null));
System.out.println("String, " + new TestClass() == null);
}
private static class TestClass {
public String toString() {
return "false";
}
}
private static boolean getFalse() {
return false;
}
}
Why does the last System.out.println print a different output than the others? I have no idea, is this a bug? Is it to do with the plus operator? The StringBuilder?

"String, " + new TestClass() == null
would be considered as
("String, " + new TestClass()) == null
therefore prints out false
(you can check out more details in the operator precedence)

Specifically writing from an array of courses to a csv file

I'm having trouble using a method from a class that I have written. The following method was added to a class I created named Course. The goal is to write all of the properties of the object on one line as a String.
// method to return properties as a CSV string on one line
public String toCSVString(Course c) {
String record = c.campus + ","
+ c.course + ","
+ c.section + ","
+ c.crn + ","
+ c.credits + ","
+ c.time + ","
+ c.days + "\n";
return record;
} //end toCSVString()
OK, so after adding that method to the Class. I then began to create a method (which is called from the main method) needed to write from a Course array to a CSV File which calls the above method. This is the method I wrote.
// add a method here to write from an array of courses to a CSV file
public static void writeCSV(Course[] courseArray, int count) throws Exception {
//create a File class object and give the file the name employees.csv
java.io.File courseCSV = new java.io.File("courses.csv");
//Create a Printwriter text output stream and link it to the CSV File
java.io.PrintWriter outfile = new java.io.PrintWriter(courseCSV);
//Iterate the elements actually being used
for (int i=0; i < count ; i++) {
outfile.write(courseArray.toCSVString(courseArray[i]));
}//end for
outfile.close();
} //end writeCSV()
I'm having trouble with the line that starts with "outfile.write"
In my code, I am having trouble getting Netbeans to locate the toCSVString method which is defined after the toString method in the Course class. Originally that line in the code looked like this:
outfile.write(toCSVString(courseArray[i]));
But my IDE could not find it so I added the instance of the course object in front of it. However, I am still having trouble.
Does anybody see what I am doing wrong?
EDIT #1
Here is the Course class in my program. I am having issues with the toCSVString method.
class Course implements Serializable {
private String campus; // the campus on which the course is offered
private String course; // the course number, such as CSCI 111
private String section; // the section number
private String crn; // the CRN for this section
private int credits; // the number od credits for the course
private String time; // the time the course is offered, such as 8:00 to 10:00 A.M.
private String days; // the Days the course is offered, suhc as MW
// constructors
Course() {
}
Course(String course, String section, String crn, int credits) {
this.course = course;
this.section = section;
this.crn = crn;
this.credits = credits;
} // end Course() initalizing
// muatator methods
public void setCampus(String cmp) {
this.campus = cmp;
}// end setCampus()
public void setCourse(String crse) {
this.course = crse;
}// end setCourse()
public void setSection(String sect) {
this.section = sect;
} // end setSection()
public void setCRN(String crn) {
this.crn = crn;
} // end setCRN()
public void setCredits(int cr) {
this.credits = cr;
} // end setCredits()
public void setTime(String tm) {
this.time = tm;
}// end setTime()
public void setDays(String days) {
this.days = days;
}// end setDays()
// accessor methods
public String getCampus() {
return campus;
} // end getCampus()
public String getCourse() {
return course;
} // end Course()
public String getSection() {
return section;
} // end getSection()
public String getCRN() {
return crn;
} // end getCRN()
public int getCredits() {
return credits;
} // end getCredits()
public String getTime() {
return time;
} // end getTime()
public String getDays() {
return days;
} // end getDays()
// method to compare by CRN using the String class compareTo()
public int compareTo(Course other) {
return this.crn.compareTo(other.getCRN());
} // end compareTO()
// method to return properties as a string
public String toString() {
return campus + " "
+ course + " "
+ section + " "
+ crn + " "
+ credits + " "
+ time + " "
+ days;
} // end toString()
// method to return properties as a CSV string on one line
//public String toCSVString(Course c){
public String toCSVString (Course c){
String record = campus + ","
+ course + ","
+ section + ","
+ crn + ","
+ credits + ","
+ time + ","
+ days + "\n";
return record;
} //end toCSVString()
}// end class Course

You have:
outfile.write(courseArray.toCSVString(courseArray[i]));
You mean:
outfile.write(courseArray[i].toCSVString(courseArray[i]));
As toCSVString is a member of Course, not of Course[] (courseArray is a Course[] and you are attempting to call .toCSVString() on the array itself, which is not valid).
Also note that in this form, it is redundant to pass the Course as a parameter, as you are not using it and you also would want this instead of some other Course anyways. I recommend either ditching that parameter entirely (since it is unused):
public String toCSVString () { // <- c wasn't actually used
String record = campus + "," // <- and this. is implied here
+ course + ","
+ section + ","
+ crn + ","
+ credits + ","
+ time + ","
+ days + "\n";
return record;
}
And you simply call it as:
outfile.write(courseArray[i].toCSVString());
Or, if you prefer you can make the method static and use the parameter (although that does not get you any particular benefit in this situation):
public static String toCSVString (Course c) {
String record = c.campus + ","
+ c.course + ","
+ c.section + ","
+ c.crn + ","
+ c.credits + ","
+ c.time + ","
+ c.days + "\n";
return record;
}
If you choose the static approach then you call it as:
outfile.write(Course.toCSVString(courseArray[i]));