I am trying to find either some references to point me on the right track with passing an object with all of it's properties still in tact after it's been created. Currently I am trying to do this through an interface but it seems to just create a new object everytime without the properties. Example below :
import java.util.ArrayList; import java.util.List; public interface TPerson{ //public Person p = null; } class Thrower { Person p;
[code]....
When I implement the interface on the other objects as soon as I call the setP method shown above it seems to just create a new one even though I pass the object to the method I want to use.
Where should I keep a collection of instances of my custom class? In the class itself in a static variable?
class Item { int quantity; static ArrayList<Item> list = new ArrayList<Item>(); Item(int q) { quantity = q; list.add(this); } // Some methods and whatnot. }
Is it fine like this or should I implement the collection elsewhere? What say you?
I’m teaching myself Java. I am a fairly proficient programmer in other languages, but this is the first OO language I’m doing.I have a question that is a bit hard to summarize. Or it should be: how can I pass on an object (or variable) to an event listener?
I am writing an application in which you can play a Sudoku game. I have separated the “logic” or the “model”(the classes with Sudoku data structures and methods to manipulate them) from the presentation (the view and the controller).The main method starts off as follows:
SudokuModel model = new SudokuModel(); SudokuView viewController = new SudokuViewController(model);
The first line creates class for the logic and the second line creates the class for the view and the controller. Since the view and the controller need access to the business logic, the model is passed on to the ViewController class.The SudokuViewController class creates the user interface in Swing and it handles the user input. For the user input I have created a number of listeners, like this:
table.addKeyListener(this);
Now these listeners need access to the model since they update it. However, as far as I’m aware the only parameter passed on to an event listener is the event itself. So these event listeners do not have direct access to the model, even though it is passed on to the constructor of the class SudokuViewController.
To circumvent this, I made model2 an attribute (variable) of the class SudokuViewController. The constructor of the class sets this variable as follows:
model2 = model;
Now the event listeners have access to model2, which they can manipulate.This works. However, I think it is an ugly solution, introducing an additional object (model2). I’d like to pass on the object named model to the event listener, but this doesn’t seem to be possible.
When I hit the url at the first time my call goes to the spring controller and sets the userDetails objects in the modelAndView.addObject("userDetails", userDetails.getUserDetails()) and returns the userDetails.html page. if I click any link in the same page i want to pass same (userDetails) object thru javascript or jquery and calls the another(controller) method and returns the same (userDetails.html) page.
It means how can I pass the java object thru javascript or jquery and calls the controller. If I get the same object in my controller i can avoid calling the db again.
public void randomCreate(ParentObject obj){ int x = random(0-4); //pseudo int y = random(0-4); //pseudo create new ParentObj(x,y); }
ParentObject is actually abstract, so you would only ever pass one of its children objects to it, and a child object of that type would be created. It seems like there should be a way to pass a type, rather than an object, and then create an instance later down, but I don't know if that is actually possible, or if it is poor programming style.
import java.io.FileNotFoundException; public class PrimaClasse { public static void main(String[] args) throws FileNotFoundException { SecondaClasse oggettoSeconda = new SecondaClasse(); oggettoSeconda.controlloNomi();
[code]....
Now it's working and from the main class i can controll the second class BUT. i want that is the main class that ask the user name, and i want pass that value to the second class. what code i must change?why eclipse wants me insert this import java.io.FileNotFoundException; and this throws FileNotFoundException for not give me an error?
Assuming that we have two classes B and C which inherit from class A. What is the best way to pass a parameter from an object of class B to an object of class C by the use of class A without using static variable and without defining a get function in B?
As the title says, how can I pass a value from one variable to another class?
Example:
So here I'm switching one frame to another, called "redigeraProjekt". Now in this class, I want the value from .getSelectedIndex() pass over to that class. I've tried to use the variable "valIListan" but it cannot find it. Probably because it's "private" (?)
valIListan = listaAllaSpelProjekt.getSelectedIndex(); redigeraProjekt npj = new redigeraProjekt(); // "switching" to another frame npj.setVisible(true); this.setVisible(false);
package com.emp; public class salarybean { private String name; private Double days; private Double id; public String getName() { return name;
[code]...
now i want to retrieve all these values in another servlet where i want to do some calculation but not able to retrieve it is showing null and indicating for this value in my eclispe IDE " Iterator<salarybean> itr=list.iterator(); "
public class Time extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, java.io.IOException
Right so I have my ItemsPage Jframe Class and I'm trying to pass my TotalPrice variable to my CashPay so I can calculate the change. CashPrice runs and works but when I try run ItemsPage it does nothing I don't even get errors. I tried to remove that small section of trying to pass the variable to CashPay and it worked perfectly so I 100% know that's the problem. This section "public ItemsPage() { Pounds = ""; //super();
Scanner sc = new Scanner(System.in); CashPay sendTotalPrice = new CashPay(); //System.out.println("Enter your amount"); TotalPrice = sc.nextDouble(); sendTotalPrice.printTotalPrice(TotalPrice); " Here is complete code for both classes, I'm using GUI builder.
I just want to know how to pass an Attribute along with its value from servlets to a plain Java class. Im using java beans but it's showing null...So as an alternative im using session to access variables in java class..
Suppose I have an enum class named Faction and one of the constants is named DAUNT. I created a class of the enum DAUNT but how can I pass in a DAUNT faction type in for Daunt?
Java Code:
public enum Faction { ALMIGHTY, AMBITION, DAUNT, RESTLESS, CAN; }
//new file public class Daunt { public Daunt() { } } mh_sh_highlight_all('java');
in my progrm there are three diff array of objects...namely garments..gadgets and home app...now one who buys from each of these sections will have to make a bill at last...when he choses to make the bill he will be shown the list of products he bought and their details (like price...brand...etc)...so i thought that while he orders each product(which is done in a previous method called purchase()...)....(each product is stored as an object in there diif arrays namely garments...gadgets ...appliances)....each of those object will be copied in a new array in a diif class...then that array print will give me the desired result...
is this approach correct...?and if its correct then how can i pull out a specific obj frm a stored array of object and then save it in a new array....?
I have an stand alone client to use a remote ejb with some methods. All works fine, but when I pass an entity class as parameter from the stand alone client to the remote ejb, the entity class is received as null.
"You might wonder what happens when a static synchronized method is invoked, since a static method is associated with a class, not an object. In this case, the thread acquires the intrinsic lock for the Class object associated with the class. "What is a Class object associated with a class. Google search rather finds material about the Object class.
I want to know is there any way we can call parent class method using child class object without using super keyword in class B in the following program like we can do in c++ by using scoop resolution operator
class A{ public void hello(){ System.out.println("hello"); } } class B extends A{ public void hello(){ //super.hello(); System.out.println("hello1");
How to create object for "class B" and call the "function_B" from other different class D where class D has no connection with class A? Here is my program.
public class A(){ void print(){} } class B{ void function_B(){} } class C{ void function_C(){} }
Here, A, B, C are in the same package. But class D is in different package.
I am a beginner here at JAVA and I am trying to program a Gratuity Calculator using both interface class and object class but it keeps on compiling with errors saying "cannot find symbol".I tried everything to fix it but it just keeps on stating symbol.
[CODE] public class GratuityCalculator extends JFrame { /* declarations */
// color objects Color black = new Color(0, 0, 0); Color white = new Color(255, 255, 255); Color light_gray = new Color(192, 192, 192);
Design a class named Person and its two subclasses named Student and Employee. Make Faculty and Staff subclasses of Employee. There is also a MyDate class as explained below. A person has a name, address, phone number, and email address. A student has a status (freshman, sophomore, junior, or senior). Define the status as an integer which can have the value 0 (for "Freshman"),
1 (for "Sophomore"), 2 (for "Junior"), and 3 (for "Senior"),
but don't allow the status to be set to any other values. An employee has an office, salary, and dateHired. The dateHired is a MyDate field, which contains the fields: year, month, and day. The MyDate class does not explicitly inherit from any class, and it should have a no-arg constructor that sets the year, month, and day to the current year, month, and day. The MyDate class should also have a three-argument constructor that gets three int arguments for the year, month and day to set the year, month and day.
A faculty member has office hours and a rank. Define the rank as a String (for values like "Professor" or "Instructor"). A staff member has a title, which is also a String. Use data types for the fields as specified, or where one is not specified, use a data type that is appropriate for the particular field. Write a test program called TestEveryone.java that creates a Person, Student, Employee, Faculty, and Staff object, and invoke their toString() method (you don't need to call the objects' toString() method explicitly).
Note: Your MyDate.java class is the object class that your dateHired field is created from in the Employee.java class.
Do not use the Person, Employee or Faculty classes defined on pages 383 and 384 of the book. Create new ones.Here is the code I have so far concerning the employee and MyDate.
public class Employee extends Person { private String office; private double salary; //private MyDate dateHired; //7 argument constructor for employee public Employee(String name, String phoneNumber, String email, String address, String office, double salary /*MyDate dateHired*/) { super(name, phoneNumber, email, address);
In the process of creating a new class, I need to move my main method from the class SaveDate to the class DynamicTest. Below I have listed the code of both classes.The objective is to be able to run my program from the DynamicTest Class. I need understanding the process of moving my main method to a different class and creating an Object of a class and calling its method.
public class SaveData { private static final Map<String, Object> myCachedTreeMap = new TreeMap<String, Object>(); public static final List<String> getLines(final String resourceParam, final Charset charset) throws IOException{ System.out.println("Please get: "+resourceParam); if (myCachedTreeMap.containsKey(resourceParam) ) { // Use the cached file, to prevent an additional read.