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Why there is the need of the constructor if you can assign the value to variables by the help of the methods ..?
A constructor is what allocates memory for an object. If you didn't call a constructor, you would have no object in which to assign values.
1 Explain the concepts of constructor and destructor Do you have to declare a constructor every time you create a class?
You only need a constructor if the default constructor will not suffice. Often times, it is useful to have a constructor that takes common parameters so that you do not have to write additional code. For example, a Point class might have a constructor for Point(int x, int y), which would be a shortcut for assigning x and y independently. Other classes may not need any default values assigned, and for this, it is acceptable to just use the default constructor. Finally, some classes are virtual, static, or abstract, and so may not need a constructor because the constructor is unnecessary (static), or may be defined elsewhere (virtual, abstract).
What kind of education does a constructor need?
construction engineer
Why constructor rather than classes in java?
Constructor is not an alternative to class. In Java, you create classes; the classes contain methods - including the constructor, which can be viewed as a special method. If you want to have a constructor, you need a class that surrounds it, so it's not one or the other.
What is a constructor and its mandatory to use constructor in a class?
Constructor is a special block of code similar to the method that is used to initialize the state of objects. If you do not define a constructor in a class, Java compiler automatically put a default constructor in the class.
Can you call a constructor from another if a class has multiple constructors?
Yes. All you need to do is to specify the correct number of arguments to invoke the correct constructor.
Is scenery an abstract noun?
The noun scenery is a concrete noun for specific scenery, the immediate physical surroundings or the set on a stage. The noun scenery is an abstract noun when used in general, for example: I need a vacation from the dreary scenery of the city. The scenery of the countryside would be so soothing.
Why do you need a constructor as a class member?
A constructor is not a mandatory member that we need to code specifically for a class. While creating a class, even if we miss out coding the constructor, Java would create a default constructor all by itself. The constructor is usually the place where we initialize things that are required by the class. Hence it is a good practice to code the constructor for our class. Tip: If you do not want anyone to instantiate your class, you can declare the constructor as private. In that way no other class can instantiate your class.
Default constructor in java?
If you don't type a constructor into your class code, a default constructor will be automatically generated by the compiler. The default constructor is ALWAYS a no-arg constructor. (Obviously the compiler has no clue what all arguments you might want for your class. So it takes the safe way out with a no argument constructor) A no-arg constructor is not necessarily the default (i.e., compiler-supplied) constructor, although the default constructor is always a no-arg constructor. The default constructor is the one the compiler provides! While the default constructor is always a no-arg constructor, you're free to put in your own no-arg constructor.
Do we need Always need constructor in every class?
Objects are constructed. You can't make a new object without invoking a constructor. In fact, you can't make a new object without invoking not just the constructor of the object's actual class type, but also the constructor of each of its superclasses including the Object class itself! Constructors are the code that runs whenever you use the keyword new.
What is an empty constructor?
An empty constructor takes no arguments and calls the default constructor
What is the general syntax of a default constructor?
There is no such thing as 'the general syntax of a default constructor'. A default constructor is one that is generated by the compiler if you don't specify any constructors at all. Semantically speaking, it is public and takes no arguments, but this is not 'syntax'.
