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What is the difference between initializing and instantiating?
Instantiation: The new keyword is a Java operator that creates the object. Initialization: The new operator is followed by a call to a constructor, which initializes the new object.
What is meant by instantiating a class in Java?
Instantiate in Java means to call a constructor of a Class which creates an an instance or object, of the type of that Class. Instantiation allocates the initial memory for the object and returns a reference.
What happens during class loading?
After class loading, initialization of the class takes place which means initializing all static members of the class. 2) a static method of a class is invoked. 3) a static field of Class is assigned. 4) a static field of a class is used which is not a constant variable.
What is this keyword in Java?
The this keyword refers to the current object in a method or constructor. The most common use of the this keyword is to eliminate the confusion between class attributes and parameters with the same name (because a class attribute is shadowed by a method or constructor parameter). Return the current class object.
How do you initialize a class?
To initialize a class member variable, put the initialization code in a static initialization block, as the following section shows. To initialize an instance member variable, put the initialization code in a constructor.
Which class will load first in java?
A Java Classloader is of three types: BootStrap ClassLoader: A Bootstrap Classloader is a Machine code which kickstarts the operation when the JVM calls it. It is not a java class. Its job is to load the first pure Java ClassLoader.
What’s the difference between instantiating an object in Java?
Certain things can only occur after a class has been initialized to a specific point, etc. Instantiating an object can only occur after the class has been loaded and initialized (though all methods do not need to have been verified). The size of the object is gotten from the class and that much heap is located and zeroed.
How does a variable get initialized in Java?
A reference to the object that was created is returned from the new keyword. This is when values are put into the memory that was allocated. This is what the Constructor of a class does when using the new keyword. A variable must also be initialized by having the reference to some object in memory passed to it.
How is a class initialized in Java JVM?
When a Java class is “loaded” into the JVM the class representation must be initialized in several ways. The class’s “constant pool” is expanded into a runtime structure and some values in it are initialized. The superclass of the class is located (via the constant pool) and attributes of it extracted.