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what are the Key points about a constructor?




->we have 2 kinds of constructor
1. Zero arguments constructs (blank/default constructor)
2. Parameterized constructor
->in any java class, if any kind of constructor is not defined by the developer, java compiler by default provides a zero argument constructor to the class.
* Zero argument constructors are also known as default constructor.
->we can have any no. of constructors in a java class as soon as their signature doesn’t match. it is known as constructor overloading.
->a constructor is called by JVM (java virtual machine) implicitly (automatically) whereas, a normal instance method should be called explicitly (i.e. the instance method called using reference only).
->constructor is the first method called on the object. After constructor execution only, any other instance method is called.
Additional:
->Constructor can’t call explicitly with reference, only the constructor called by JVM only.
->implicit default constructor-the java compiler automatically provide the constructor.
->Explicit default constructor-the developer providing the constructor in the program explicitly.
->Constructor is the initial state of the object.
->“new” operator instructs the JVM and JVM construct the object.

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