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Java Cannot Reference This Before Supertype

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share|improve this answer answered Aug 21 '15 at 17:48 RealSkeptic 22.4k61939 add a comment| up vote 0 down vote You need to call super as the very first thing in each There is no emoticon for what I am feeling! The fact that Java/C++ disagree on what to do indicates to me that one may have wandered out of the OOP standard practices. posted 10 years ago Originally posted by Ken Blair: I still don't see any explanation of why. http://tcsmacs.net/java-cannot/java-cannot-reference-before-supertype.php

Does the electoral vote count ever get reallocated between states? Not the answer you're looking for? If execution of any of these initializers results in an exception, then no further initializers are processed and this procedure completes abruptly with that same exception. First thing that came to mind. –morganw09dev Aug 21 '15 at 17:49 add a comment| up vote 0 down vote Every class has to call the constructor of its superclass as http://stackoverflow.com/questions/10963775/cannot-reference-x-before-supertype-constructor-has-been-called-where-x-is-a

Call To Super Must Be First Statement In Constructor

Also check this:https://docs.oracle.com/javase/tutorial/java/IandI/super.html There is a note on this page: If a constructor does not explicitly invoke a superclass constructor, the Java compiler automatically inserts a call to the no-argument constructor we have a reference).thats why there is no error when "this" with class variables as arguments is called in the super class. xparse processor with multiple arguments C++ calculator using classes Would we find alien music meaningful?

Is Area of a circle always irrational more hot questions lang-java about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life Right? What is role of palladium in hydrogenation reactions? private final String NAME = "U-Boot"; private final int SIZE = 2; private final int GUNPOWER = 1; public Submarine(){ super(SIZE,GUNPOWER,NAME); //Here it gets underlined } SIZE, GUNPOWDER, and NAME all

How often should I replace windscreen wiper blades? Java Super How do I make an alien technology feel alien? What do I do? http://stackoverflow.com/questions/33106957/java-cannot-reference-before-supertype-constructor So I was trying small programs.

Wrong way on a bike lane? Yes it is already declared, 4 lines up } public MyClass(int p, int q) { super(p,q); this.p = p; this.q = q; } } class MySuperclass { static int x,y; // you're trying to send the private field roomNumber as a parameter. public Room(int roomNumber, boolean enSuite) In Java if the parent constructor can't make the call due to any condition, then the compiler should show it as an error.

Java Super

In the example: class Point { int x, y; Point() { x = 1; y = 1; } } class ColoredPoint extends Point { int color = 0xFF00FF; } class Test http://stackoverflow.com/questions/30895112/cannot-reference-before-supertype-has-been-called-java If the variables are already allocated and initialized to their default values then in theory you'd think it'd be useable. Call To Super Must Be First Statement In Constructor Zener diodes in glass axial package - not inherently shielded from photoelectric effect? Super Keyword In Java In your example that would not have been a problem because the code path in both constructors is dead simple, but I'd like to raise awareness for this because it is

C++ calculator using classes What is this c. 1948 private plane with a sliding canopy? http://tcsmacs.net/java-cannot/java-cannot-create-java-virtual-machine-1.php The super constructor is always the first thing called, whether it is explicitly or implicitly called. The super constructor is always the first thing called, whether it is explicitly or implicitly called. Formula 1 rebus Why are wavelengths shorter than visible light neglected by new telescopes? Java Inheritance

Will boring a cylinder affect its longevity thereafter? If the answer is no, make it static. Imagine that this class we're talking about has a polymorphic method, and the subclass implementation accesses subclass variables -- say, it prints them to System.out, just for fun. click site The memory is allocated and the variables have their default value.

Can anybody just go through the following? Teenage daughter refusing to go to school How EXACTLY can +=/-= operators be interpreted? So the class level variable may be delared but are not initialized with the default values, so the compiler is complaining.

The problem is that Inner2's superclass is itself an inner class Inner1, thus making Inner2's default constructor illegal since it requires an enclosing instance to be supplied to the constructor.

So the class level variable may be delared but are not initialized with the default values, so the compiler is complaining. Thank you everone again I realy appreciate your help JEAN Ernest Friedman-Hill author and iconoclast Marshal Posts: 24212 35 I like... The only thing I can come up with is that it would mislead developers into thinking the variable initializers had been executed, but that's just a guess. You need to update your Ellipse constructor to call the super with values.

I haven't actually written java in about 10 years so I forgot that part. Post Reply Bookmark Topic Watch Topic New Topic programming forums Java Java JSRs Mobile Certification Databases Caching Books Engineering Languages Frameworks Products This Site Careers Other all forums Forum: Programmer Certification I am seen in darkness and in light, What am I? navigate to this website more hot questions question feed lang-java about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / Arts Culture / Recreation

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Note that the invocation of the superclass constructor occurs before instance initializers and instance variable initializers. Right? The problem is that due to how default constructor is defined, we really have the following: // Same as above but with default constructor included explicitly public class Outer { class My assumption has always been (based not on inspection of the source, but on how I would do it myself) is that the default initialization happens automatically because the allocator effectively

If that constructor invocation completes abruptly, then this procedure completes abruptly for the same reason. By "uninitialized", you mean the variable has been initialized to its default value (null, 0, or false), but it hasn't been set to that value the programmer wants to initialize to, Not the answer you're looking for? Do humans have an ethical obligation to prevent animal on animal violence?

It is not clear from the title of your question. –EJK Jun 17 '15 at 14:53 NAME is not static and can't be called at that point. –Dragondraikk Jun The reason you can use a static variable is because the variable belongs to the class and by the time a constructor is ever invoked the class has been loaded and