Every class has a constructor whether it’s a normal class or a abstract class . Constructors are not methods and they don’t have any return type. Constructor name should match with class name . Constructor can use any access specifier, they can be declared as private also.
Read moreWhy does JPA need a no-arg constructor?
2 Answers. Because it often happens that the JPA provider has to instantiate your domain object dynamically . It cannot do so, unless there is a no-arg constructor – it can’t guess what the arguments should be.
Read moreWhat is no-arg constructor?
No-Arg Constructor – a constructor that does not accept any arguments . Parameterized constructor – a constructor that accepts arguments. Default Constructor – a constructor that is automatically created by the Java compiler if it is not explicitly defined.
Read moreDo you need a no-arg constructor?
No-argument constructor A constructor that has no parameter is known as the default constructor. If we don’t define a constructor in a class, then the compiler creates a default constructor(with no arguments) for the class .
Read moreWhat are inner classes used for in Java?
Simply put, Java allows us to define classes inside other classes. Nested classes enable us to logically group classes that are only used in one place, write more readable and maintainable code and increase encapsulation .
Read moreIs it a good practice to use inner classes?
Nested Class can be used whenever you want to create more than once instance of the class or whenever you want to make that type more available . Nested Class increases the encapsulations as well as it will lead to more readable and maintainable code.
Read moreWhy are Java inner classes bad?
Now you are clear that inner classes keep reference to outer class .So image scenario where you pass reference of inner class to other outer world class and then reference never gets released to in turn OuterClass is also referenced , hence leak. So this makes using inner classes bad if not used prpperly.
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