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Suppose your object is: o = new MyClass(); Then you can simply do: o.getClass().getCanonicalName() to get the fully qualified class name(FQCN) in Java. This can be required in special cases like below: I am using Hibernate to bind my objects into relational database. When I want to identify unique objects, and when I want to properly implement ...


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The getClass() or the instanceof are the easiest ways to know the Object's class. We can use the instanceof in a if loop, to check the type. The getClass will help get the runtime type of the object.


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obj instanceof Class however using instanceof is often considered a design flaw, in that polymorphism is preferred e.g. rather than if (obj instanceof Supervisor) { handleSupervisor(obj, args); } if (obj instanceof Programmer) { handleProgrammer(obj, args); } you create a method in a shared interface and move the logic into each implementation ...


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The difference between class variables and instance variables, is simply a question of who knows what?. An instance variable is only known (= bound) to that concrete instance - hence the name. public class Person { private String firstName; private String lastName; [...] } The definition of a class is like a blueprint for building ...


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Instance Variable: Instance variables are declared in a class, but outside a method, constructor or any block. Instance variable belongs to the instance of a class or you can say that instance variable belongs to the object. Instance variable have separate value of each and every instance of the class. Class InstanceDemo { // this instance variable ...


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They both are member variables, meaning that both are associated with a class. Now of course, there are differences between the two: Instance variables: These variables belong to the instance of a class, thus an object. And every instance of that class (object) has it's own copy of that variable. Changes made to the variable don't reflect in other ...


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It is explained here (with an example Bicycle class with class variable numberOfBicycles and instance variables cadence, speed, gear & id): Sometimes, you want to have variables that are common to all objects. This is accomplished with the static modifier. Fields that have the static modifier in their declaration are called static fields or class ...


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It depends. Without any synchronisation and without volatile or atomic variables it does not make a difference. However, if those methods change the object-state you will need some form of synchronisation, otherwise multiple threads would overwrite changes from other threads or just not see the change. Synchronisation is not free, volatile variables and ...



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