All Instances Of Same Class Change Each Other Private Variable
May 2, 2015
I have a class named Base and a private variable named _hopcount i have 10 instances of class base i use _hopcount as creteria to some if but other instances edit _hopcount so i want to prevent _hopcount edit by other instances; I want to have private variable which other instances of same class can't modify it.
public class Base extends TypedAtomicActor {
private int _hopcount = 0;
if(_hopcount <= 3) {
some code;
}
public function() {
_hopCount += 1;
}
}
I'm working on a project that contains multiple classes. Each class contains and must contain only PRIVATE variables. Here's my issue. When my test code calls for a new instance of "StudentClass" as so:
StudentClass studentClass = new StudentClass(offeredClass.getClassIdNumber(), offeredClass.getClassName(), offeredClass.getClassroom());
The corresponding constructor won't let me initialize it's variables because they are declared private within another class, as shown here:
When getClassName, getClassroom, and getClassIdNumber are passed to a toString() method elsewhere in my test code. the output is returned just fine. When passed through the StudentClass, I'm getting Null across the board.
public class Class1 extends AbstractClass { //stuff } public class Class2 extends AbstractClass { //stuff }
within another class I have a private variable with the type of the Abstract class, and within one of the methods I assign an object to the the variable like this:
public class Test { private AbstractClass temp; public testMethod(){ Class1 anObject = new Class1(); temp = anObject; } }
As below code showing that you cannot directly access the private variable as i understood,
public class EncapsulationDemo{ private int ssn; private String empName; private int empAge; //Getter and Setter methods public int getEmpSSN(){ return ssn; } public String getEmpName(){ return empName;
public class Car { //instance variables ---------------------- private String make; private String model; private int year; private double vehiclePrice; private double downPayment; private double milesPerGallon;
[code]....
I created this class "Car" (also not sure if it's correct) and need to write a driver program that creates two instances of the class Car. One must use the default constructor, and the other must use the non-default constructor. It must demonstrate the methods used in the Car class using those instances.
public class DriverCar { public static void main(String[] args) { Car car1 = new Car("Toyota", "Corolla", 2013, 20000, 3000, 35); Car car2 = new Car("Ford", "Taurus", 2005, 14000, 1500, 25); System.out.println(car1);
What I have to do: Use Applet to create two instances of the Employee class. Display the data on the Graphics object. Display in the applet the names and values of all of the instance variables in each instance of the class. Also display the value of any static variables.
What I'm doing:
import java.applet.Applet; import java.awt.*; public class EmployeeApplet extends Applet { public static int topSalary = 195000; int hoursPerWeek; public static void setTopSalary (int s) { if (s > topSalary)
[Code]...
I'm not able to display hours per week for e1 and e2.
I have to write a test class for a Contacts class called ContactTest and store the instances of Contacts created into a LinkedList.The ContactTest class should implement the addition andremoval of contacts to the Linked List and display its contents.
So far I have this, which stores the information entered into a Linked List, the problem is I don't know how I go about doing the addition and removal part.
Contacts Class
public class Contacts implements InterfaceContacts { String fname; String lname; String phone; String email; //constructors public Contacts( ){ this("****", "****", "****", "****");
How do I use two constructors and I'm having trouble with using char for gender...
Write a program to test the Person class defined below. Your test program should create two instances of the class (each to test a different constructor) and test each of the methods. You are also required to illustrate the error in trying to access private data members from the client class (for clarity temporarily change the private modifier to public and test again). See screenshots below for sample output.
The screen shots are displayed as:
p1 name = Not Given Age = 0 Gender = U p2 name = Jane Doe Age = 0 Gender = F p1 name = John Doe Age = 25 Gender = M
and
PersonTester.jave:20: name has private access in Person System.out.println("p2 name = " + p2.name + "Age = " + p2.age + "Gender = " + p2.gender); PersonTester.jave:20: age has private access in Person System.out.println("p2 name = " + p2.name + "Age = " + p2.age + "Gender = " + p2.gender); PersonTester.jave:20: gender has private access in Person System.out.println("p2 name = " + p2.name + "Age = " + p2.age + "Gender = " + p2.gender);
3 errors
Here is the class given :
class Person { // Data Members private String name; // The name of this person private int age; // The age of this person private char gender; // The gender of this person
import java.util.Scanner; import java.util.ArrayList; public class Problem1 { public static void main(String[] args) { Scanner scan = new Scanner(System.in); ArrayList<String> list = new ArrayList<String>();
[Code] ....
There is an error and says that my ArrayList has private access. I can't figure out how to fix it.
The code runs but when I enter "Quit", the program just stops. The arraylist isn't printed out?
When creating a class with a constructor, why does one have to create private variables (attributes) to be used as parameters by the object? The object's parameters will be set to be exactly equal to the private variables (attributes), so what is the point of having the private variables (attributes) Why are both private variables (attributes) and parameters needed when they are set to be equal each other anyway?
1) When a variables are declared "Private" How should it be accessed from the driver class ? Sometimes i get an error in driver class saying "your variable is declared Private" why am I getting this error ...
The document says "Private" declared variables should be accessed only through methods. What does that mean.
GoodEmployee is defined who has ALL the following properties:
He should be married. He should have 2 or less than 2 children. His middle name should start with "k" but not end with "e" The last name should have more than 4 characters The character "a" should appear in the last name at least two times. The name of one of his children should be "Raja"
isMarried true if the employee is married. noOfChild the number of children of the employee. middleName the middle name of the employee lastName the last name of the employee. childNames the array of the names of the children of the employee
When we say derived class that means copy of base class plus subclass specific implementations. But when it comes to private members it cannot be accessible in subclass scope. Does it mean byte code generated for subclass doesn't has byte code of private members of super class ?
The String class stores the characters of the string internally as a private char[] and calling someString.length() results in getting the length field from the character array. I am looking to get the details on how the length is implemented. I understand it is a field, but in the original question I provide sample code and really want to know if/how the resulting byte code may differ when compiled, perhaps I am just not seeing the simple answer through my confusion.
If i have a class(lets say class name is Approval) with the following private members: String recip_id, Int accStat, String pDesc, String startDate How can i create public get and setter methods for these private members of the class?
I am wondering if there is a way in jave to use enums WITHIN a class (without creating a separate enum class) without using private static final. Something like as folows:
class My Class { myEnum {ACTIVE, INACTIVE, PENDING}; }
Okay, I am supposed to implement the functionalities of the Set class using a private data member of type ListReferencedBased<E>,how the ListReferenceBased works with what I am trying to accomplish.I am trying to complete Set.java, and I have barely started and much of the code doesn't work. ListReferenceBased was given to me completed.
import java.util.Iterator; pubic class ListReferenceBased<E> implements ListInterface<E>, Iterable<E>{ /** reference to the first element of the list */ private Node<E> head; /** number of items in list */ private int numItems;
From what i understand static methods should be called without creating an instance of the same class . If so why would they return an instance of the same class like in the following : public static Location locateLargest(double[][] a) , the Location class being the same class where the method is defined . I don't understand this , does it mean that every field and every method in the class must be static ? Meaning that you cannot have instances of the class because everything is static . Or it's just a mistake and the class Location cannot have a static method: public static Location locateLargest(double[][] a) ?
I have a program with 4 classes, all of them in the same package, one of them is the Main class, and in that class I declared a variable named "port" of type int. One of the 3 another ones is the class Connection class, which it requires the port variable. I want to use this variable in the Connection class. How can I do it?Both classes are shown below:
Main.java package server; /* Imports */ /* Another variables */ int port; /* <-- IS THIS ONE */
So it seems to reason that many JavaFX applications will want to dynamically change CSS styles. Is the best way to do this via the <node>.getStyleClass().add("classname")? The underlying data structure is an observable list. So lets say one has 5 styles that simply change the fill color of a circle to 5 different colors respectively. So if I have a condition in which I want to dynamically apply 1 of these 5 styles, the way I currently do this is by defining all 5 styles as strings in a list using a static initializer, then I call <node>.getStyleClass().removeAll(list), then getStyleClass().add("classname"). I do this to avoid adding the same style over and over and inflating the underlying list. Is this the correct way to manage dynamic CSS styles?
So I know there is a few different way to implement a splash screen. My app has definitely gotten larger over the last few months of development and I have noticed there is about a 5 second delay between when I run the application to when I see the main stage. I was thinking a splash screen would be nice to fill this time period. I have not had time to prototype using a Preloader and I fear that using an alternate, lightweight stage on startup would still take too long of a delay. I was actually thinking that using the nice and simple JVM argument "-splash:<image name>" would be simple, easy and effective. Unfortunately when I try to do this, the splash screen comes up but never goes away.
