A default constructor is a constructor that either has no parameters, or if it has parameters, all the parameters have default values . If no user-defined constructor exists for a class A and one is needed, the compiler implicitly declares a default parameterless constructor A::A() .
Read moreWhy does Java need a default constructor?
Java doesn’t require a constructor when we create a class. However, it’s important to know what happens under the hood when no constructors are explicitly defined. The compiler automatically provides a public no-argument constructor for any class without constructors . This is called the default constructor.
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