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|Java - Interview Questions and Answers|
|Ans. Java provides a default constructor ( no argument ) if no constructor is provided by the programmer. Java makes a check during pre compilation if there is any constructor provided by the programmer. If any constructor is provided, Java understands that programmer has provided all the mechanism for initialization and construction of the object and may not even intend to create objects by calling a no argument constructor. For example - One may like to have objects created with self defined state otherwise restrict its creation.|
We make the constructor private if we want to make a class singleton as we would like to restrict creation of new objects using new operator and default constructor. Similar could be the situation wherein we would like to construct objects in a particular manner only.
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|What is a Default Constructor ?|
|Will Compiler creates a default no argument constructor if we specify only multi argument constructor ?|
|Difference between Class#getInstance() and new operator ?|
|Can we create an object if a Class doesn't have any constructor ( not even the default provided by constructor ) ?|
|Does every class needs to have one non parameterized constructor ?|
|Variable of the boolean type is automatically initialized as?|
|Why Java provides default constructor ?|
|In a case where there are no instance variables what does the default constructor initialize?|
|Is it mandatory to have a default constructor ?|