There is an r missing public void actionPerfomed(ActionEvent e) ^^^ public void actionPerformed(ActionEvent e) solved Method is not abstract and does not override method in Interface error
Looking it up, the thing you’re using (“Ready to program Java”) comes with Java 1.4. It’s ancient. So … no, @Override isn’t allowed, and also you can not set the layout directly on the JFrame. See: http://docs.oracle.com/javase/1.4.2/docs/api/javax/swing/JFrame.html#setLayout(java.awt.LayoutManager) By default the layout of this component may not be set, the layout of its contentPane should be … Read more
Not all “String in Java are interned”. Try reading something from a file or console, those Strings aren’t “interned”, thus equals() (and also hashcode()) needs to be overriden. 1 solved What is the need to override equals method in String class? [closed]
why output is 0 not “lol” ? because you are printing an integer and not an instance of that Main class you can do the following public class Main { @Override public String toString(){ return “lol”; } public static void main(String[] args) { // int aaa=0; Main myMain = new Main(); System.out.println(myMain); } } note … Read more
You override the method in D, even if it is just to forward to one (or both) of the B and C overrides. (You have to do this even if you never call print on an expression whose static type is D, since an A* elsewhere could point to a D.) 1 solved What to … Read more
AAA ref1 = new CCC(); BBB ref2 = new CCC(); CCC ref3 = new CCC(); Is there anyone who can explain how it works inside the complier? In this case ref1 is a reference to a AAA object and since CCC inherits from AAA it is also an AAA so this assignment is allowed by … Read more
Of course, because run is a part of an anonymous inner class. In this method: public void start(long delay, long period) { … updateTask = new TimerTask() { // !! method run() should be override public void run() { // TODO } }; … } You cannot override run because it isn’t a part of … Read more
what are the methods “public override bool equals(object obj)” and “public override int gethashcode()” doing? [closed] solved what are the methods “public override bool equals(object obj)” and “public override int gethashcode()” doing? [closed]
Would overriding func1 work? class Class(file1.Class2): def func1(self): print “Class3.func1” c = Class3() c.func2() Since func2 is not defined in Class3, Class2.func2 is called. However, in the body of that function, self is still an instance of Class3, so self.func1() calls Class3.func1, not Class1.func1. That is different from d = Class2() d.func2() where self in … Read more
You create an instance of B that is lets say “Bigger”, but the variable ‘a’ is converted into class A that is “Smaller” and contains the method print A. You did something similar to: A : IClass B : IClass The interface exposes some method that is in both A and B, and you to … Read more
Your Debug.CallObjectEvent() method explicitly instantiates a Call object and calls the overridden method in that class: public static class Debug { internal static void CallObjectEvent(string log) { new Call().CallEvent(new Log(log, Timer.GetTime())); } } The CallEvent() method in the Call class simply calls base.Event(), which resolves to IDebug.Event(). The Program.Event() override is never invoked because Program … Read more
Seems like a basic setter… It should go like public void setCapacity(int newCapacity) { this.capacity = newCapacity; } solved java method which can be changed