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Ans. 1. Memory is allocated from heap to hold all instance variables and implementation-specific data of the object and its superclasses. Implemenation-specific data includes pointers to class and method data.
2. The instance variables of the objects are initialized to their default values.
3. The constructor for the most derived class is invoked. The first thing a constructor does is call the constructor for its superclasses. This process continues until the constructor for java.lang.Object is called,as java.lang.Object is the base class for all objects in java.
4. Before the body of the constructor is executed, all instance variable initializers and initialization blocks are executed. Then the body of the constructor is executed. Thus, the constructor for the base class completes first and constructor for the most derived class completes last.
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Ans. New operator in Java creates objects. Constructor is the later step in object creation. Constructor's job is to initialize the members after the object has reserved memory for itself.
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Q4. Difference between new operator and Class.forName().newInstance() ?
Ans. new operator is used to statically create an instance of object. newInstance() is used to create an object dynamically ( like if the class name needs to be picked from configuration file ). If you know what class needs to be initialized , new is the optimized way of instantiating Class.
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Q5. Difference between Class#getInstance() and new operator ?
Ans. Class.getInstance doesn't call the constructor whereas if we create an object using new operator , we need to have a matching constructor or copiler should provide a default constructor.
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Ans. Java expects the superclass ( Object Class ) constructor to be called while creation of any object. So super constructor is called in case there are no instance variables to initialize.
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