public class Code{
//many properties
//...
final String NEWLINE;// ohh a final property!
void creation() //this method is for avoid repetition of code
{
//final ...
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Why is it a good practice to mark a class with only private constructors as final? My guess is, it is to let other programmers know that it cannot be sub-classed.
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public class User
{
private final String _first_name;
private final String _last_name;
private final String ...
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I wanted to split the constructor of my class into parts. But I have a problem...
Is it possible to initialize a final value in a method called inside constructor? It has ... |
Is it possible to make a modification as specified in the class below, and initialize a member for existing callers to some default value, say null?
Member is required to be private ... |
In Java, I can't create instances of abstract classes. So why doesn't eclipse scream about the following code?
public abstract class FooType {
private final int myvar;
...
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What exactly is the difference between a final class and having a class constructor as private.
I know both can't be subclassed(correct me if i am wrong). Is their any difference?
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In final variable passed to anonymous class via constructor, Jon Skeet mentioned that variables are passed to the anonymous class instance via an auto-generated constructor. Why would I not be ... |
import java.util.*;
public Class C
{
final Vector v;
C()
{
v=new ...
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I understand that constructors cannot be marked final because they can never be inherited and overridden, and so it is redundant. However, you can declare an interface as abstract even though it's obvious that it is, and you can declare a private method as final even though it too will never be inherited. So my question is, why is there a ... |
If you use nested classes, it's possible to subclass a class with a final constructor using another class contained within the same top-level class. Private does not prevent this sort of access. Another difference is that if you have a private constructor, it's always possible to add another non-private constructor as well, and then the class can be subclassed. Most importantly, ... |
If I remember correctly (don't actually use either of these much myself), a private constructor means an instance of the object can only be created by itself. In other words you couldn't create an instance of Object1 from Object2, only from inside Object1. While I'm sure there's a use for this I've never come across it in my job. As for ... |
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well peter iam thinking about how far java is flexible and robust if final keyword is allowed for a constructor hardly no class will have more than one constructor if i think one constructor is enough for a class then i may have a final keyword for a constructor why not a constructor final? but with the static constructor you can ... |
Hi Again, "A constructor cannot be abstract, static, final, native, or synchronized." I understand on why it can't be all of the above, except "final". why can't we have a final constructor, i understand constructors are not inherited, hence no chance/case of overriding etc. But why is it not allowed at all ? |
The soul is dyed the color of its thoughts. Think only on those things that are in line with your principles and can bear the light of day. The content of your character is your choice. Day by day, what you do is who you become. Your integrity is your destiny - it is the light that guides your way. - ... |
public class single { static single objectTest; private single(){ } public single getObj() { return objectTest; } public void setObj(single objectTest) { this.objectTest = objectTest; } public static single getObjectReference() { if(objectTest == null) { objectTest = new single(); System.out.println("Object created"); }else{ System.out.println("Object already created"); } return objectTest; } public static void main(String args[]){ single.getObjectReference(); single.getObjectReference(); } } |
Not like this you can't. Until the parent constructor has been called you can't use any attributes of the child since the object hasn't been built yet, so those attributes don't really exist. What is it you are trying to achieve? A default value to use if the empty constructor is called? If so then make X static. |
I just read that when a var is not to be changed in the program you should declare it final. So I make my map var private final private final Map map; public Game() { try { map = resources.getMap("test.xml"); } catch(Exception ex) { logger.severe(ex) } But this doesn't work, the try catch seems to hide the map from the constructor. ... |
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