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Calling superclass in main method

I've just learned about superclasses and subclasses and the homework is pretty simple: have 2 classes and a test class to call and print the attributes. Below is my code from all 3 classes. My question is, why isn't the department attributes printing in my main? Everything else prints just fine, I just can't get that last little bit to print. I think it has something to do with super...thank you in advance! Second computer course and I'm finally feeling I sort of get it, so that's improvement from the first class I took!
public class Employee {
private String firstName;
private String lastName;
private int employeeID;
private double salary;
public Employee () {
firstName = null;
lastName = null;
employeeID = 0;
salary = 0.00;
}
public String getFirstName() {
return firstName;
}
public String getLastName() {
return lastName;
}
public int getEmployeeID() {
return employeeID;
}
public double getSalary() {
return salary;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public void setEmployeeID(int employeeID) {
this.employeeID = employeeID;
}
public void setSalary(double salary) {
this.salary = salary;
}
public String employeeSummary () {
String employeeSummary = "Employee's name is: " + getFirstName() + " " + getLastName() +
". The employee's ID number is " + getEmployeeID() +
". The employee's salary is " + getSalary();
System.out.println(employeeSummary);
return employeeSummary;
}
}
public class Manager extends Employee {
private String departmentA;
public Manager() {
super();
departmentA = null;
}
public String getDepartmentA() {
return departmentA;
}
public void setDepartmentA(String departmentA) {
this.departmentA = departmentA;
}
public void EmployeeSummary() {
super.employeeSummary();
System.out.println("The employee's department is " + departmentA);
}
}
public class ManagerDerivation {
public static void main(String[] args) {
Manager person = new Manager();
person.setFirstName("Ron");
person.setLastName("Weasley");
person.setEmployeeID(2345);
person.setSalary(65000.00);
person.setDepartmentA("Department of Magical Law Enforcement");
person.employeeSummary();
return;
}
}

Method names are case sensitive. EmployeeSummary() does not override employeeSummary() because it uses a different name.
To avoid mistakes like this, always include the #Override annotation on overridden methods. If you include that annotation and make a mistake in the method signature, compilation will fail.
Note also that your return types for the two methods are different (String and void). Overridden methods must have compatible return types.

There is some spelling (employeeSummary vs. EmployeeSummary) mistakes and return types dont match, in Employee should be
public void employeeSummary () {
String employeeSummary = "Employee's name is: " + getFirstName() + " " +
getLastName() +
". The employee's ID number is " + getEmployeeID() +
". The employee's salary is " + getSalary();
System.out.println(employeeSummary);
}
then in Manager
public void employeeSummary() {
super.employeeSummary();
System.out.println("The employee's department is " + departmentA);
}

Checking if an object is in arraylist in Java

So here is assignment :
A student entity has a name and an address (both represented by an object of class Name and Address), in addition to a university ID, and a course schedule represented by an ArrayList of Courses
Your code should not allow the creation of Two students with the same university ID
So I'm thinking of using ArrayList to hold a list of student and check if student exists or not before create a new student. sorry, this is my first question so I'm trying my best to explain it:
This is my Address class:
public class Address {
private int streetNumber;
private String streetName;
private String city;
private String state;
private int province;
private String country;
public Address (int streetNumber,String streetName,String city,String state,int province,String country)
{
this.streetNumber=streetNumber;
this.streetName=streetName;
this.city=city;
this.state=state;
this.province=province;
this.country=country;
}
public int getStreetNumber() {
return streetNumber;
}
public void setStreetNumber(int streetNumber) {
this.streetNumber = streetNumber;
}
public String getStreetName() {
return streetName;
}
public void setStreetName(String streetName) {
this.streetName = streetName;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public int getProvince() {
return province;
}
public void setProvince(int province) {
this.province = province;
}
public String getCountry() {
return country;
}
public void setCountry(String country) {
this.country = country;
}
public String toString() {
return " [streetNumber=" + streetNumber + ", streetName=" + streetName
+ ", city=" + city + ", state=" + state + ", province="+province+", country="
+ country + "]";
}
public boolean equals(Address add)
{
if(add==null)
{
return true;
}
if(this.getClass()!=add.getClass())
{
return false;
}
Address address=(Address) add;
return streetNumber==address.streetNumber &&
province==address.province && streetName.equals(address.streetName)
&& city.equals(address.city)&& state.equals(address.state)&& country.equals(address.country);
}
}
This is my Name class
public class Name {
private String firstName;
private String lastName;
private char middle;
public Name (String fiName,String laName, char middle)
{
this.firstName=fiName;
this.lastName=laName;
this.middle=middle;
}
public String getFirst()
{
return firstName;
}
public void setFirst(String first)
{
firstName=first;
}
public String getLast()
{
return lastName;
}
public void setLast(String last)
{
lastName=last;
}
public char getMiddle()
{
return middle;
}
public void setMiddle(char midd)
{
middle=midd;
}
/*public String toString()
{
return "[First Name= "+ firstName +" Last Name "+ lastName+" Middle Name "+ middle +"";
}*/
}
This is my Student class:
public class Student {
private int studentId;
private Name name;
private Address address;
boolean a;
ArrayList<Course> courseSchedule = new ArrayList<Course>();
ArrayList<Student> student=new ArrayList<Student>();
public Student(String fiName,String laName, char middle,int stNumber,String stName,String city,String state,int province,String country,int id)
{
if(student.contains(id))
{
System.out.println("Student cannot be same id");
}
else
{
address= new Address(stNumber,stName,city,state,province,country);
name=new Name(fiName,laName,middle);
this.studentId=id;
student.add();
}
}
public int getID()
{
return studentId;
}
public void setId(int id)
{
this.studentId = id;
}
public ArrayList<Course> getCourseSchedule()
{
return courseSchedule;
}
public void setCourseSchedule(ArrayList<Course> courseSchedule)
{
this.courseSchedule = courseSchedule;
}
public void addCourse(Course c) {
courseSchedule.add(c);
}
public void dropCourse(Course course) {
courseSchedule.remove(course);
}
}
My question is how can you add Student Object into Student ArrayList
and how can I check if the Student Id exists in ArrayList with contains() method
student.contains(id) this line right here it does not seem to be right
I hope im explain my question a little clear now. Sorry for my english also.

You would not keep a list of Student objects within the class for Student. Your ArrayList<Student> student=new ArrayList<Student>(); does not belong there.
You would have another structure or collection kept elsewhere named something like StudentBody. When a student is instantiated, it is added to the StudentBody collection.
List< Student > studentBody = new ArrayList< Student >() ; // This list is stored somewhere else in your app.
You could loop a List of Student objects in the StudentBody object. For each you would access the UniversityId member field and compare to your new one being added.
Or you could use a Map, where the key is a UniversityId object and the value is a Student object. Check for an existing key before adding.
These solutions ignore the important issue of concurrency. But that is likely okay for a homework assignment in a beginning course in programming.

Use A HashMap() for collecting information based on unique Ids.
public class Student {
private int studentId;
private Name name;
private Address address;
private static HashMap<Integer,Student> students = new ConcurrentHashMap<>(); // Make a static Map so all objectrs shared same data
public Student(String fiName,String laName, char middle,int stNumber,String stName,String city,String state,int province,String country,int id)
{
if(students.contains(id))
{
System.out.println("Student can be same id");
}
else
{
address= new Address(stNumber,stName,city,state,province,country);
name=new Name(fiName,laName,middle);
this.studentId=id;
students.put(id,this); // use this to add current object
}
}

Java Eclipse: My code's output is skipping a line and I don't know why [duplicate]

This question already has answers here:
Scanner is skipping nextLine() after using next() or nextFoo()?
(24 answers)
Closed 5 years ago.
The title says it all. This is a basic Customer class that the user inputs their name/age/street address/city/state/zip code and then the program formats the input and returns it to the user. When I run this class it skips over the 'Street Address' and goes straight to 'City' and thus I can't get it to let me input my street address.
I've looked at a fairly similar issue in this thread here: Java is skipping a line (Strings in a Scanner ??)
However I haven't derived anything from that that has helped me solve this issue. I'm sure its extremely basic but I'm just unable to catch it and don't have much time to work on this today, so any tips/help are appreciated!
public class Customer {
String name;
String streetAddress;
String city;
String state;
String zip;
int age;
//default constructor
public Customer() {
name = "Unknown";
streetAddress = "Unknown";
city = "Unknown";
state = "Unknown";
zip = "Unknown";
age = 0;
}
//constructor to accept values for the above attributes
public Customer(String n, String sAdd, String c, String st8, String z, int a) {
name = n;
streetAddress = sAdd;
city = c;
state = st8;
zip = z;
age = a;
}
//getters and setters
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getStreetAddress() {
return streetAddress;
}
public void setStreetAddress(String streetAddress) {
this.streetAddress = streetAddress;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
public String getState() {
return state;
}
public void setState(String state) {
this.state = state;
}
public String getZip() {
return zip;
}
public void setZip(String zip) {
this.zip = zip;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String displayAddress() { //returns a string with the complete formatted address
String showAddress;
showAddress = ("\nStreet Address: " + streetAddress + "\nCity: " + city + "\nState: " + state + "\nZip Code: " + zip);
return showAddress;
}
public String displayAddressLabel() { //returns a string with the customers name/age
String nameAgeAddress;
nameAgeAddress = ("Name: " + name + "\nAge: " + age);
return nameAgeAddress;
}
//main method
public static void main(String[] args) {
Scanner scan = new Scanner(System.in);
//creating an object of the Customer class
Customer actualCustomer = new Customer();
//getting info for displayAddressLabel() and displayAddress
System.out.println("Enter your name: ");
actualCustomer.setName(scan.nextLine());
System.out.println("Enter your age: ");
actualCustomer.setAge(scan.nextInt());
//issue is here
System.out.println("Enter your street address: ");
actualCustomer.setStreetAddress(scan.nextLine());
System.out.println("Enter the city you live in: ");
actualCustomer.setCity(scan.nextLine());
System.out.println("Enter the state you live in: ");
actualCustomer.setState(scan.nextLine());
System.out.println("Enter your zip code: ");
actualCustomer.setZip(scan.nextLine());
System.out.println(actualCustomer.displayAddressLabel());
System.out.println(actualCustomer.displayAddress());
}
}

After this line:
actualCustomer.setAge(scan.nextInt());
you should call:
scan.nextLine();
because after scan.nextInt() there is a new line character left to be read (after inputting int you press Enter to confirm your input and you're missing to read it from your Scanner). Instead of writing these two lines:
actualCustomer.setAge(scan.nextInt());
scan.nextLine();
You might want to change it to:
actualCustomer.setAge(Integer.parseInt(scan.nextLine()));
It will get rid of new line character.

Java string sorting

This is no homework.Its an exercise I came across in a book.
Build a class named Name which represents the name of a person.The class should have fields that represent first name ,last name ,and fathersname.
The class should have these methods :
public Name (String fn,String f_n,String ln)
/* initializes the fields of an object with the values fn,f_n and m.
fn means first name
ln means last name
f_n means fathersname btw. */
public String getNormalOrder(); //returns the name of the person in the normal order : first name,fathers name,last name.
public String getReverseOrder(); //returns the name of the person in the reverse order : last name,fathers name,first name.
public boolean compare (String fn,String f_n,String ln); // Returns true if the first name is the same with fn,fathers name is the same with f_n, last name with ln.If the opposite happens it returns false.
Build a program named TestName which tests the methods of the class Firstname.
My solution
public class Name {
String fn;
String f_n;
String ln;
public Name(String initialfn, String initialf_n, String initialln) {
fn = initialfn;
f_n = initialf_n;
ln = initialln;
}
public String getNormalOrder() {
return fn + " " + f_n +
" " + ln;
}
public String getReverseOrder() {
return ln + ", " + f_n +
" " + fn + " ";
}
}
How about the third method which is comparing? Also how do I test the class?

For a flexible solution:
public enum NameMember {
FIRSTNAME, SECONDNAME, FATHERSNAME;
}
The Name class:
public class Name {
private final String firstName;
private final String secondName;
private final String fathersName;
public Name(String firstName, String secondName, String fathersName) {
this.firstName = firstName;
this.secondName = secondName;
this.fathersName = fathersName;
}
public String getName(NameMember member1, NameMember member2, NameMember member3) {
StringBuilder sb = new StringBuilder();
return sb.append(getMember(member1)).append(" ")
.append(getMember(member2)).append(" ")
.append(getMember(member3)).toString();
}
public String getMember(NameMember member) {
switch (member) {
case FIRSTNAME:
return firstName;
case SECONDNAME:
return secondName;
case FATHERSNAME:
return fathersName;
default:
return null;
}
}
#Override
public String toString() {
return getName(NameMember.FIRSTNAME, NameMember.SECONDNAME, NameMember.FATHERSNAME);
}
}
A NameComparator (flexible) class:
import java.util.Comparator;
public class NameComparator implements Comparator<Name> {
private NameMember nameMember;
public NameComparator(NameMember nameMember) {
this.nameMember = nameMember;
}
#Override
public int compare(Name name1, Name name2) {
return name1.getMember(nameMember).compareTo(name2.getMember(nameMember));
}
}
And the main class (test drive):
public static void main(String args[]) {
List<Name> names = new ArrayList<>();
names.add(new Name("Alice", "Burda", "Christophe"));
names.add(new Name("Ben", "Ashton", "Caine"));
names.add(new Name("Chane", "Bagwell", "Alex"));
names.add(new Name("Ann", "Clinton", "Brad"));
System.out.println("NAMES ORDERED BY FIRST NAME:");
Collections.sort(names, new NameComparator(NameMember.FIRSTNAME));
printNames(names);
System.out.println("\nNAMES ORDERED BY SECOND NAME:");
Collections.sort(names, new NameComparator(NameMember.SECONDNAME));
printNames(names);
System.out.println("\nNAMES ORDERED BY FATHERSNAME:");
Collections.sort(names, new NameComparator(NameMember.FATHERSNAME));
printNames(names);
}
private static void printNames(Collection<Name> names) {
names.stream().forEach(System.out::println);
}

java toString() is returning null from class [closed]

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Closed 10 years ago.
This is Java, using BlueJ.
I have four classes called Person, Letter, Address and PhoneNumber. In each, I override the toString() method to return a concatenated string of the values I want from the class. When calling the Letter toString(), it is returning null on all values.
The idea is to use the hard coded information, pass it into the appropriate class, and return it in a standard letter format.
Am I headed in the right direction for printing out the information hard coded, or should I go a different route? This is a homework problem, but I feel I have hit a brick wall.
Here are the classes:
public class Person
{
private static String aPerson;
private String first;
private String middle;
private String last;
private Address address;
private PhoneNumber phone;
public String getFirst()
{
return this.first;
}
public void setFirst(String FirstName)
{
this.first = FirstName;
}
public String getMiddle()
{
return this.middle;
}
public void setMiddle(String MiddleName)
{
this.middle = MiddleName;
}
public String getLast()
{
return this.last;
}
public void setLast(String LastName)
{
this.last = LastName;
}
public Address getMyAddress()
{
return this.address;
}
public void setMyAddress(Address Address)
{
this.address = Address;
}
public PhoneNumber getMyPhoneNum()
{
return this.phone;
}
public void setMyPhoneNum(PhoneNumber Number)
{
this.phone = Number;
}
public Person()
{
aPerson = getFirst() + getMiddle() + getLast() + getMyAddress() +
getMyPhoneNum();
}
public String toString()
{
return aPerson;
}
}
PhoneNumber:
public class PhoneNumber
{
private String number;
private int areaCode = 0;
private int phonePrefix = 0;
private int phoneLineNum = 0;
private int phoneExtension = 0;
public String getNumber()
{
return number;
}
public void setNumber(String Number)
{
number = Number;
}
public int getAreaCode()
{
return areaCode;
}
public void setAreaCode(int AreaCode)
{
areaCode = AreaCode;
}
public int getPrefix()
{
return phonePrefix;
}
public void setPrefix(int Prefix)
{
phonePrefix = Prefix;
}
public int getPhoneLineNumber()
{
return phoneLineNum;
}
public void setLineNum(int PhoneNumber)
{
phoneLineNum = PhoneNumber;
}
public int getExtension()
{
return phoneExtension;
}
public void setExtension(int Extension)
{
phoneExtension = Extension;
}
}
Address:
public class Address
{
private String state;
private String anAddress;
private String address;
private String city;
private int zip = 0;
public String getState()
{
return state;
}
public void setState(String State)
{
state = State;
}
public String getAddress()
{
return address;
}
public void setAddress(String Address)
{
address = Address;
}
public String getCity()
{
return city;
}
public void setCity(String City)
{
city = City;
}
public int getZip()
{
return zip;
}
public void setZip(int Zip)
{
zip = Zip;
}
public Address()
{
anAddress = getState() + getAddress() + getCity() + getZip();
}
public String toString()
{
return this.anAddress;
}
}
Letter:
public class Letter
{
private Person to;
private Person from;
private String body;
private String finishedLetter;
public Person getTo()
{
return to;
}
public void setTo(Person newValue)
{
to = newValue;
}
public Person getFrom()
{
return from;
}
public void setFrom(Person newValue)
{
from = newValue;
}
public String getBody()
{
return body;
}
public void setBody(String newValue)
{
body = newValue;
}
public Letter()
{
finishedLetter = getTo() + " \n" + getFrom() + " \n" + getBody();
}
public String toString()
{
return finishedLetter;
}
}
And main:
public class MainClass
{
public static void main(String args[])
{
PhoneNumber phone1 = new PhoneNumber();
phone1.setAreaCode(417);
phone1.setPrefix(447);
phone1.setLineNum(7533);
phone1.setExtension(0);
PhoneNumber phone2 = new PhoneNumber();
phone2.setAreaCode(210);
phone2.setPrefix(336);
phone2.setLineNum(4343);
phone2.setExtension(9850);
Address address1 = new Address();
address1.setState("MO");
address1.setAddress("1001 East Chestnut Expressway");
address1.setCity("Springfield");
address1.setZip(65807);
Address address2 = new Address();
address2.setState("TX");
address2.setAddress("4800 Calhoun Road");
address2.setCity("Houston");
address2.setZip(77004);
Person person1 = new Person();
person1.setFirst("Shane");
person1.setMiddle("Carroll");
person1.setLast("May");
person1.setMyAddress(address1);
person1.setMyPhoneNum(phone1);
Person person2 = new Person();
person2.setFirst("Ted");
person2.setMiddle("Anthony");
person2.setLast("Nugent");
person2.setMyAddress(address2);
person2.setMyPhoneNum(phone2);
Letter aLetter = new Letter();
aLetter.setTo(person2);
aLetter.setFrom(person1);
aLetter.setBody("This is the body");
System.out.println(aLetter.toString());
}
}

Your Letter constructor is calling methods such as getTo() and getFrom() before those fields have been filled. Don't do this since your finishedLetter String will never be correctly "finished". i.e.,
public Letter()
{
finishedLetter = getTo() + " \n" + getFrom() + " \n" + getBody();
}
will always result in null + "\n" + null + "\n" + null
Perhaps that sort of code should be in the toString() method instead.

When your letter is constructed using new Letter(), it initializes its instance field finishedLetter with several null values. Because to, from, and body haven't yet been set with their corresponding setters, their getters return null, resulting in finishedLetter being equal to "null \nnull \nnull".
To fix this, I one approach is to define the finishedLetter in the toString() method itself. This will both fix the issue and take a more object-oriented approach to the program design.
// remove constructor (if you wish) and finishedLetter field
public String toString() {
return getTo() + " \n" + getFrom() + " \n" + getBody();
}
An even better approach is to require to, from, and body, as parameters in the Letter constructor.
// remove finishedLetter field
public Letter(Person to, Person from, String body) {
this.to = to;
this.from = from;
this.body = body;
}
public String toString() {
return getTo() + " \n" + getFrom() + " \n" + getBody();
}