How to deal with resource leak problem in scanner class

How to deal with resource leak problem in scanner class - java

The code below gets name and age of the animal and displays it. When I give 1 for dogs, for the first time the code runs correctly and when I give 1 for second time, i.e. when count is changed to 2, the code gets only the age and skips the name.
This happens for both Dog and Cat classes. And also the IDE shows that there is a resource leak problem near the Scanner scan. Please give me a solution
NOTE: This is the first time I'm programming in java, so I can't explain the problem clearly. So please excuse my flaws.
/**
*
*/
package pets;
import java.util.Scanner;
/**
* #author Karthic Kumar
*
*/
public class pets {
public static int total = 0;
public class Dog
{
int age;
String name;
int serial_no=1;
Scanner scan = new Scanner(System.in);
public void get_name()
{
System.out.println("enter the name of the dog: ");
name = scan.nextLine();
}
public void get_age()
{
System.out.println("enter the age of the dog: ");
age = scan.nextInt();
}
public void display()
{
System.out.println(serial_no+". the name of the dog is "+ name +" and his age is "+ age+"\n");
}
public void total_display()
{
System.out.println("total animals = "+total);
}
}
public class Cat
{
int age;
String name;
int serial_no=1;
Scanner scan = new Scanner(System.in);
public void get_name()
{
System.out.println("enter the name of the cat: ");
name = scan.nextLine();
}
public void get_age()
{
System.out.println("enter the age of the cat: ");
age = scan.nextInt();
}
public void display()
{
System.out.println(serial_no+". the name of the dog is "+ name +" and his age is "+ age);
}
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner scan = new Scanner(System.in);
int type,count=1;
pets object_1 = new pets();
pets.Dog dog = object_1.new Dog();
pets.Cat cat = object_1.new Cat();
System.out.println("press one for dog and two for cat and 3 for total");
while(count<=10)
{
System.out.println("\n"+count+". ");
type = scan.nextInt();
if(type == 1)
{
dog.get_name();
dog.get_age();
dog.display();
dog.serial_no +=1;
pets.total+=1;
}
if(type == 2)
{
cat.get_name();
cat.get_age();
cat.display();
cat.serial_no+=1;
pets.total+=1;
}
if(type==3)
{
dog.total_display();
}
if(type <=4 && type >=100)
{
System.out.println("enter correctly");
}
count++;
}
}
}

In order to fix your problem, you simply need to add a call to method nextLine() of class Scanner in your get_age() method in both class Cat and class Dog.
Here is the entire get_age() method from class Dog with the required addition.
public void get_age() {
System.out.println("enter the age of the dog: ");
age = scan.nextInt();
scan.nextLine(); // I added this line.
}

Related

Method being called twice for some strange reason?

For some reason, after I add a pet named "Oliver" the main menu prints out twice with the "invalid choice" line along with it. I just need another set of eyes to look at it because I have been looking at it for hours on end and been fixing little mistakes to no avail.
The code when ran looks like this:
/*Welcome to the pet store.Type the letter to make your selection
A. List the pets in the store.
B. Age up the pets
C. Add a new pet
D. Adopt a pet
E. Quit
C
Please type in a name
Oliver
Please type in an age
22
Oliver has just been added to the store!
Welcome to the pet store.Type the letter to make your selection
A. List the pets in the store.
B. Age up the pets
C. Add a new pet
D. Adopt a pet
E. Quit
Invalid choice
Welcome to the pet store.Type the letter to make your selection
A. List the pets in the store.
B. Age up the pets
C. Add a new pet
D. Adopt a pet
E. Quit*/
Here is my main class code:
private static void mainmenu(){
System.out.println("Welcome to the pet store.Type the letter to make
your selection");
System.out.println("A."+" " + "List the pets in the store.");
System.out.println("B."+" " + "Age up the pets");
System.out.println("C."+" " + "Add a new pet");
System.out.println("D."+" " + "Adopt a pet");
System.out.println("E."+" " + "Quit");
MainPets.Getuserinput();
}
public static String Getuserinput(){
userinput=scan.nextLine();
return userinput;
}
public static void main (String [] args){
int pet3age;
String pet3name;
Pet Pet1=new Pet("Fido",3);
Pet Pet2=new Pet("Furball",1);
Pet Pet3=null;
int userinputint;
MainPets.mainmenu();
while(userinput.equals("A")||userinput.equals("B")||userinput.equals("C")||userinput.equals("D")||userinput.equals("E")){
switch(userinput){
case "C":
if (Pet3!=null&&userinput.equals("C")){
System.out.println("Sorry the store is full");
}
if(Pet3==null){
System.out.println("Please type in a name");
pet3name=scan.nextLine();
System.out.println("Please type in an age");
pet3age=scan.nextInt();
Pet3=new Pet(pet3name,pet3age);
System.out.println(pet3name + " has just been added to the store!");
}
MainPets.mainmenu();
break;
}
}
while(!userinput.equals("A")||!userinput.equals("B")||!userinput.equals("C")||!userinput.equals("D")||!userinput.equals("E")){
System.out.println("Invalid choice");
MainPets.mainmenu();
}
Here is the class with all the methods:
public class Pet {
String Name;
String AdoptionStatus;
int Age;
public Pet() {}
public Pet(String Name, int Age) {
this.Name = Name;
this.Age = Age;
}
public void SetName(String namesetup) {
Name = namesetup;
}
public String GetName() {
return Name;
}
public int GetAge() {
return Age;
}
public int ageincrease() {
return Age++;
}
public String Getadoptionstatus() {
return AdoptionStatus;
}
public void Setadoptionstatustonotadopted(int petnumber) {
AdoptionStatus="not adopted";
}
public void Setadoptionstatustoadopted(int petnumber){
AdoptionStatus="adopted";
}
}

It looks like you're trying to use static as much as possible for practice of what it does?
Anyway, see below for a minimal example of which you can build on (i.e. it will let you enter 'C' as many times as you want to 'add' new pets).
static String petname, petage;
public static void main(String[] args) {
initialText();
String userinput = userInput();
while (userinput.equals("A") || userinput.equals("B") || userinput.equals("C") || userinput.equals("D") || userinput.equals("E")) {
if(userinput.equals("C")){
System.out.println("Please type in a name");
petname = userInput();
System.out.println("Please type in an age");
petage = userInput();
Pet p = new Pet(petname, petage);
System.out.println(petname + " has been added to the store.");
}
else{
System.out.println("Option not configured yet");
//TODO - the rest of the options
}
initialText();
userinput = userInput();
}
}
public static void initialText() {
System.out.println("Welcome to the pet store.Type the letter to make your selection");
System.out.println("A." + " " + "List the pets in the store.");
System.out.println("B." + " " + "Age up the pets");
System.out.println("C." + " " + "Add a new pet");
System.out.println("D." + " " + "Adopt a pet");
System.out.println("E." + " " + "Quit");
}
public static String userInput(){
Scanner s = new Scanner(System.in);
return s.nextLine();
}
It's by no means perfect, just knocked it together very quickly to give you a chance to work on it.

How do you run a Java class from another class?

I am working on a project for school. at this point i'm just going over board, I would like to run the class bookstoreCreditPersonal if none of the following conditions are true, but I cant get it to work. any suggestions?
import java.util.Scanner;
public class bookstoreCreditPersonal {
public static void main(Object o) {
String studentNamePers;
String userType;
double studentGPAPers;
double bookstoreCreditPers;
Scanner input = new Scanner(System.in);
System.out.print("Please enter 'S' if you are the student, 'T' if you are the teacher, or 'P' if you are the Parent: ");
userType = input.nextLine();
if (userType.equals("S")) {
System.out.println("Greetings student...");
Scanner Sinput = new Scanner(System.in);
System.out.println("Please enter your(The students) first and last name :");
studentNamePers = input.nextLine();
Scanner SSinput = new Scanner(System.in);
System.out.println("Please enter your(The student's) GPA :");
studentGPAPers = input.nextDouble();
bookstoreCreditPers = studentGPAPers * 10;
System.out.println(studentNamePers + ", your GPA is " + studentGPAPers + ", and you have an available bookstore credit of $" + bookstoreCreditPers);
} else if (userType.equals("T")) {
System.out.println("Teacher");
} else if (userType.equals("P")) {
System.out.println("Parent");
} else {
System.out.println("Lets try that again, one character, in capital form only please.");
//created a class that reruns this class
runClassBSCP.call(null);
}
}
}
Here is the class runClassBSCP:
public class runClassBSCP {
public void call() {
bookstoreCreditPersonal.main(null);
}
}

You need to instantiate/create an object of the class. Then you can call the desired method with the object.
runClassBSCP bscp = new runClassBSCP();
bscp.call();
Also, your class names should always start with an uppercase letter: RunClassBSCP, rather than `runClassBSCP'. For more info, check out Code Conventions for the Java Programming Language.

Creating an array of students based on user input

I'm trying to create an array of math students, science students, and computer students based on the user input.
So basically the user should choose what student they want to add and then enter the student details.
Below I have added the code I have so far:
Main Java class:
public class Lab4 {
public static final int DEBUG = 0;
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
Student s[] = new Student[10];
s[0] = new MathStudent(4,5);
s[1] = new MathStudent(5,7);
s[2] = new MathStudent(2,8);
s[3] = new MathStudent(3,6);
s[4] = new ScienceStudent(8,9);
s[5] = new ScienceStudent(3,6);
s[6] = new ScienceStudent(4,9);
s[7] = new ComputerStudent(6,12);
s[8] = new ComputerStudent(11,14);
s[9] = new ComputerStudent(13,17);
}
}
Student class:
public class Student {
private String name;
private int age;
public String gender = "na";
public static int instances = 0;
// Getters
public int getAge(){
return this.age;
}
public String getName(){
return this.name;
}
// Setters
public void setAge(int age){
this.age = age;
}
public void setName(String name){
if (Lab4.DEBUG > 3) System.out.println("In Student.setName. Name = "+ name);
this.name = name;
}
/**
* Default constructor. Populates name,age,gender,course and phone Number
* with defaults
*/
public Student(){
instances++;
this.age = 18;
this.name = "Not Set";
this.gender = "Not Set";
}
/**
* Constructor with parameters
* #param age integer
* #param name String with the name
*/
public Student(int age, String name){
this.age = age;
this.name = name;
}
/**
* Gender constructor
* #param gender
*/
public Student(String gender){
this(); // Must be the first line!
this.gender = gender;
}
/**
* Destructor
* #throws Throwable
*/
protected void finalize() throws Throwable{
//do finalization here
instances--;
super.finalize(); //not necessary if extending Object.
}
public String toString (){
return "Name: " + this.name + " Age: " + this.age + " Gender: "
+ this.gender;
}
public String getSubjects(){
return this.getSubjects();
}
}
MathStudent class:
public class MathStudent extends Student {
private float algebraGrade;
private float calculusGrade;
public MathStudent(float algebraGrade, float calculusGrade) {
this.algebraGrade = algebraGrade;
this.calculusGrade = calculusGrade;
}
public MathStudent() {
super();
algebraGrade = 6;
calculusGrade = 4;
}
// Getters
public void setAlgebraGrade(float algebraGrade){
this.algebraGrade = algebraGrade;
}
public void setCalculusGrade(float calculusGrade){
this.calculusGrade = calculusGrade;
}
// Setters
public float getAlgebraGrade() {
return this.algebraGrade;
}
public float getCalculusGrade() {
return this.calculusGrade;
}
/**
* Display information about the subject
* #return
*/
#Override
public String getSubjects(){
return("Algebra Grade: " + algebraGrade + " Calculus Grade: "
+ calculusGrade);
}
}
scienceStudent class:
public class ScienceStudent extends Student {
private float physicsGrade;
private float astronomyGrade;
/**
* Default constructor
*/
public ScienceStudent() {
super();
physicsGrade = 6;
astronomyGrade = 7;
}
public ScienceStudent(float physicsGrade, float astronomyGrade) {
this.physicsGrade = physicsGrade;
this.astronomyGrade = astronomyGrade;
}
// Getters
public void setPhysicsGrade(float physicsGrade){
this.physicsGrade = physicsGrade;
}
public void setAstronomyGrade(float astronomyGrade){
this.astronomyGrade = astronomyGrade;
}
// Setters
public float getPhysicsGrade() {
return this.physicsGrade;
}
public float getAstronomyGrade() {
return this.astronomyGrade;
}
/**
* Display information about the subject
* #return
*/
#Override
public String getSubjects(){
return("Physics Grade: " + physicsGrade + " Astronomy Grade: "
+ astronomyGrade);
}
}
computerStudent class:
public class ComputerStudent extends Student {
private float fortanGrade;
private float adaGrade;
/**
* Default constructor
*/
public ComputerStudent() {
super();
fortanGrade = 4;
adaGrade = 9;
}
public ComputerStudent(float fortanGrade, float adaGrade) {
this.fortanGrade = fortanGrade;
this.adaGrade = adaGrade;
}
// Getters
public void setFortanGrade(float fortanGrade){
this.fortanGrade = fortanGrade;
}
public void setAdaGrade(float adaGrade){
this.adaGrade = adaGrade;
}
// Setters
public float getFortanGrade() {
return this.fortanGrade;
}
public float getAdaGrade() {
return this.adaGrade;
}
/**
* Display information about the subject
* #return
*/
#Override
public String getSubjects(){
return("Fortan Grade: " + fortanGrade + " Ada Grade: " + adaGrade);
}
}
How Would I go about this?

You can ask for the number of students with type on each input and dynamically create the object.
Here is an example
System.out.println("Enter total number of students");
int n = scannerObject.nextInt();
Student students[] = new Students[n];
for(int i=0;i<n;i++){
int type = scannerObject.nextInt();
if(type == 1)
students[i] = new MathStudent();
}
Similarly, you can write for others.

For allowing user to enter his choice as input
You can do this(interpreted by your comments)
Pseudo code -
Print:
Enter 1 for math student
Enter 2 for Science student
Enter 3 for Comp student
Input choice
Now in your code use either multiple if else or better switch statement
switch(choice){
case 1: create object of math student
break;
case 2: create object of science student
break;
case 3:create object of comp student
break;
default: if not above by default do this
}

You could use an ArrayList and switch case to make your life easier. Your code should be like this:
import java.util.ArrayList;
import java.util.Scanner;
public class Students {
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
ArrayList<Student> students = new ArrayList<>();
int age;
boolean addMore = true;
String name, gender;
Student st;
while (addMore) {
System.out.print("Give lesson (Computers, Math, Science): ");
String lesson = input.nextLine();
switch (lesson) {
case "Math":
// Read student's info
System.out.print("Give student's name: ");
name = input.nextLine();
System.out.print("Give student's gender: ");
gender = input.nextLine();
System.out.print("Give student's age: ");
age = input.nextInt();
System.out.print("Give student's Algebra grade: ");
int alg = input.nextInt();
System.out.print("Give student's Calculus grade: ");
int calc = input.nextInt();
input.nextLine(); // This is needed in order to make the next input.nextLine() call work (See here: https://stackoverflow.com/questions/13102045/scanner-is-skipping-nextline-after-using-next-nextint-or-other-nextfoo )
// Create the student object and pass info
st = new MathStudent(alg, calc);
st.setName(name);
st.setAge(age);
st.gender = gender;
students.add(st); // Adding the student in the list
System.out.println(st);
System.out.println(((MathStudent) st).getSubjects());
break;
case "Science":
// Read student's info
System.out.print("Give student's name: ");
name = input.nextLine();
System.out.print("Give student's gender: ");
gender = input.nextLine();
System.out.print("Give student's age: ");
age = input.nextInt();
System.out.print("Give student's Physics grade: ");
int physics = input.nextInt();
System.out.print("Give student's Astronomy grade: ");
int astronomy = input.nextInt();
input.nextLine();// This is needed in order to make the next input.nextLine() call work (See here: https://stackoverflow.com/questions/13102045/scanner-is-skipping-nextline-after-using-next-nextint-or-other-nextfoo )
// Create the student object and pass info
st = new ScienceStudent(physics, astronomy);
st.setName(name);
st.setAge(age);
st.gender = gender;
students.add(st); // Adding the student in the list
System.out.println(st);
System.out.println(((ScienceStudent) st).getSubjects());
break;
case "Computers":
// Read student's info
System.out.print("Give student's name: ");
name = input.nextLine();
System.out.print("Give student's gender: ");
gender = input.nextLine();
System.out.print("Give student's age: ");
age = input.nextInt();
System.out.print("Give student's Fortran grade: ");
int fortran = input.nextInt();
System.out.print("Give student's Ada grade: ");
int ada = input.nextInt();
input.nextLine();// This is needed in order to make the next input.nextLine() call work (See here: https://stackoverflow.com/questions/13102045/scanner-is-skipping-nextline-after-using-next-nextint-or-other-nextfoo )
// Create the student object and pass info
st = new ComputerStudent(fortran, ada);
st.setName(name);
st.setAge(age);
st.gender = gender;
students.add(st); // Adding the student in the list
System.out.println(st);
System.out.println(((ComputerStudent) st).getSubjects());
break;
default:
System.out.println("Wrong lesson");
addMore = false;
break;
}
if (addMore) {
System.out.println("Add another student? (y/n)");
String ans = input.nextLine();
addMore = ans.equals("y");
} else {
addMore = true;
}
}
System.out.println("Students");
for (Student student : students) {
System.out.println(student);
}
}
}
The code above asks for the lesson name (Computers, Math, Science) and if it is one of them it reads all the info about the student and the grades for the corresponding lesson. It creates the objects and adds them in the list students. When all info is added, it asks the user if he/she wants to add another student and if he writes the letter y, then all these are made again, until the user answers something different than the letter y (the letter n in most cases). After these it prints all the students' info by itterating the list.
Note: I think in your code for the ComputerStudent class, you meant to name the variable fortranGrade and not fortanGrade (change it also in the getSubjects function).
Links:
Java ArrayList
Switch Case in Java
Scanner is skipping nextLine() after using next(), nextInt() or other nextFoo() methods
I hope this helped you. If you have any questions or wanted something more you can do it.
UPDATE
The code below does the same things, but it uses for loop instead of switch case, as you asked in your comment.
package students;
import java.lang.reflect.InvocationTargetException;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.logging.Level;
import java.util.logging.Logger;
public class Lab4 {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
ArrayList<Student> students = new ArrayList<>();
int age;
boolean addMore = true;
String name, gender;
Student st;
ArrayList<Class<?>> studentClasses = new ArrayList<>();
studentClasses.add(MathStudent.class);
studentClasses.add(ComputerStudent.class);
studentClasses.add(ScienceStudent.class);
while (addMore) {
System.out.print("Give lesson (Computers, Math, Science): ");
String lesson = input.nextLine();
addMore = false;
for (Class studentClass : studentClasses) {
try {
st = (Student) studentClass.newInstance();
if (st.getLessonName().equals(lesson)) {
// Read student's info
System.out.print("Give student's name: ");
name = input.nextLine();
System.out.print("Give student's gender: ");
gender = input.nextLine();
System.out.print("Give student's age: ");
age = input.nextInt();
System.out.print("Give student's " + st.getSubjectsNames()[0] + " grade: ");
float firstSubj = input.nextFloat();
System.out.print("Give student's " + st.getSubjectsNames()[1] + " grade: ");
float secondSubj = input.nextFloat();
input.nextLine(); // This is needed in order to make the next input.nextLine() call work (See here: https://stackoverflow.com/questions/13102045/scanner-is-skipping-nextline-after-using-next-nextint-or-other-nextfoo )
// Create the student object and pass info
st = (Student) studentClass.getConstructor(float.class, float.class).newInstance(firstSubj, secondSubj);
st.setName(name);
st.setAge(age);
st.gender = gender;
students.add(st); // Adding the student in the list
System.out.println(st);
System.out.println(st.getSubjects());
addMore = true;
break;
}
} catch (NoSuchMethodException | SecurityException | InstantiationException | IllegalAccessException | IllegalArgumentException | InvocationTargetException ex) {
Logger.getLogger(Lab4.class.getName()).log(Level.SEVERE, null, ex);
}
}
if (addMore) {
System.out.println("Add another student? (y/n)");
String ans = input.nextLine();
addMore = ans.equals("y");
} else {
System.out.println("Wrong lesson. Try again.");
addMore = true;
}
}
System.out.println("Students");
for (Student student : students) {
System.out.println(student);
}
}
}
You also need to add the functions in the classes as mentioned bellow:
Student class:
public String getLessonName(){
return "";
}
public String[] getSubjectsNames(){
return new String[] {"", ""};
}
MathStudent class:
#Override
public String[] getSubjectsNames(){
return new String[] {"Algebra", "Calculus"};
}
#Override
public String getLessonName(){
return "Math";
}
ComputerStudent class:
#Override
public String[] getSubjectsNames(){
return new String[] {"Fortran", "Ada"};
}
#Override
public String getLessonName(){
return "Computers";
}
ScienceStudent class:
#Override
public String[] getSubjectsNames(){
return new String[] {"Physics", "Astronomy"};
}
#Override
public String getLessonName(){
return "Science";
}
Changes: The code firstly creates an arraylist with the student classes (studdentClasses) and adds all the classes for the students that are currently in the project (MathStudent, ComputerStudent, ScienceStudent). Then the user adds the lesson's name. Then (instead of the switch case) there is a for loop which itterates through the studdentClasses list and checks if the lesson's name that the user has written is the same with a student's class by using the getLessonName function. After that all the info for the student are asked and the grades for the subjects, and for the question (Give student's Physics grades) it uses the function getSubjectsNames. All the other things are like before.

You have a main class, that's what you need essentially, but you need to read from command line. Great, run from command line. Once you run, pay attention to what you did, you can pass parameters there as well. once you pass parameters, they go in line. This line is logically splitable, so split it within you code. for instance by pair of numbers after some key word like science and until next keyword and put again from java and ask a new question once you there.

Name output shows "null" Java

I am making a game-ish type of thing with three classes, combined. NOT HOMEWORK; hobby.
Codes for three classes:
Runner:
public class CounterGameRunner
{
// instance variables - replace the example below with your own
public static void main(String [] args){
Scanner input = new Scanner(System.in);
CounterGameCounter game = new CounterGameCounter();
System.out.println("You want to play a game I see. What is your name?");
String name = input.next();
game.NameIn(name);
CounterGAME game1 = new CounterGAME();
game1.actual();
}
}
Actual Game:
public class CounterGAME
{
// instance variables - replace the example below with your own
Scanner input = new Scanner(System.in);
int number;
int count=1;
boolean loop = true;
public CounterGAME(){
}
public void actual(){
CounterGameCounter game2 = new CounterGameCounter();
System.out.println("Guess a number between 1 and 101, see how many times you get it!");
number=input.nextInt();
int r = (int)(Math.random() * (100) + 1);
while(loop==true){
if(number < r){
System.out.println("Too small, try again");
number = input.nextInt();
count++;
game2.Counter(count);
} else if(number == r){
System.out.println("Wow, you won! Who'd have thought?");
count++;
game2.Counter(count);
break;
System.out.println(game2.done());
} else if(number > r){
System.out.println("Too large, try again");
number = input.nextInt();
count++;
game2.Counter(count);
}
}
}
}
Counter Class:
public class CounterGameCounter
{
// instance variables - replace the example below with your own
private String Name;
String done1;
int correct;
public CounterGameCounter(){
}
public String NameIn (String nm){
Name = nm;
return Name;
}
public String NameOut(){
return Name;
}
public void Counter(int count){
correct = count;
}
public int getCount(){
return correct;
}
public String done(){
done1 = "Name: " + NameOut() + "\n" +
"Times Answered: " + getCount();
return done1;
}
}
Problem:
The counter works properly and everything else displays and functions properly in the end. However, any name I input in the beginning always shows "null" while running the program. Why?

Your variable names are really confusing, and there are a lot of bad practices in your code, but null in name is because you create a new Counter in CounterGAME:
public void actual(){
// here
CounterGameCounter game2 = new CounterGameCounter();
// more code
}
Change actual to receive a CounterGameCounter:
public void actual(CounterGameCounter game2){
// more code
}
And call it like:
public static void main(String [] args){
Scanner input = new Scanner(System.in);
CounterGameCounter game = new CounterGameCounter();
System.out.println("You want to play a game I see. What is your name?");
String name = input.next();
game.NameIn(name);
CounterGAME game1 = new CounterGAME();
game1.actual(game);
// more stuff
}
FREE TIPS:
use String getName() and void setName(String)
start variable, object and attribute names with lowercase
String name;
Object object;
Variable names must be representative and descriptive
CounterGameCounter counterGameCounter = new CounterGameCounter();
This is also applicable to Object names:
GameCounter gameCounter = new CounterGameCounter();

try this:
String name = input.nextLine();
instead of:
String name = input.next();

Populating an array Using Polymorphism

Here is my code. I did my work a bit off. I was supposed to not just do one applicant, I was supposed to do many and I was supposed to populate the applicants into 2 different arrays, one for graduates, and one for undergraduates. I need help figuring out how to make an empty array and fill up applicants in those. A start would help
import java.util.Scanner;
public class CollegeApplicant
{
String applicantName;
String collegeName;
public String getApplicantName()
{
return applicantName;
}
public void setApplicantName(String applicantName)
{
this.applicantName = applicantName;
}
public String getCollegeName()
{
return collegeName;
}
public void setCollegeName(String collegeName)
{
this.collegeName = collegeName;
}
public void checkCollege()
{
int choice;
Graduate g = new Graduate();
Undergraduate ug = new Undergraduate();
Scanner input = new Scanner(System.in);
System.out.println("1. Undergraduate");
System.out.println("2. Graduate");
System.out.println("enter your choice ");
choice = input.nextInt();
if (choice == 1)
{
System.out.println("Enter SAT marks :");
ug.SAT = input.nextDouble();
System.out.println("Enter GPA marks :");
ug.GPA = input.nextDouble();
}
else
{
System.out.println("Enter the origin of college:");
g.collegeOrigin = input.next();
System.out.println("Status :" + g.checkCollege());
}
}
public class Undergraduate
{
double SAT;
double GPA;
}
public class Graduate
{
String collegeOrigin;
String checkCollege()
{
String information = null;
if (collegeName.equals(collegeName)) information = "Applicant is applying from inside";
else information = "Applicant is applying from outside";
return information;
}
}
}
The Client
import java.util.Scanner;
public class CollegeApplicantClient extends CollegeApplicant
{
public static void main(String[] args)
{
TestCollege tc = new TestCollege();
Scanner input = new Scanner(System.in);
System.out.println("Enter the name of applicant ");
tc.setApplicantName(input.next());
System.out.println("enter the college name of applicant ");
tc.setCollegeName(input.next());
tc.checkCollege();
}
}
Here is an example of the possible output
Name: Joe
College Applied to: Harvard
SAT: 5
GPA: 2
Name: Tom
College Applied to: Yale
College of Origin: NYU – from outside
I need to be able to put the graduates in an array and the undergrads in an array. Then display it when it's all done

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