Java constructor inheritance?

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I always thought that constructors aren't inherited, but look at this code:

class Parent {
    Parent() {
        System.out.println("S1");
    }
}

class Child extends Parent {
    Child() {
        System.out.println("S2");
    }
}

public class Test5 {
    public static void main(String[] args) {
        Child child = new Child();
    }
}

//RESULT:
//S1
//S2

It shows that Child inherited constructor. Why there is S1 on result? Is there any possibility to create 2 constructors without parameters and have only Child constructor on result without base constructor (only S2)?

Whatever you are seeing here is called as constructor chaining. Now What is Constructor Chaining:

Constructor chaining occurs through the use of inheritance. A subclass constructor method's first task is to call its superclass' constructor method. This ensures that the creation of the subclass object starts with the initialization of the classes above it in the inheritance chain.

There could be any number of classes in an inheritance chain. Every constructor method will call up the chain until the class at the top has been reached and initialized. Then each subsequent class below is initialized as the chain winds back down to the original subclass. This process is called constructor chaining.(Source)

That's what happening in your program. When you compile your program , your Child is compiled to this way by javac:

class Child extends Parent 
{ 
  Child()
  {
    super();//automatically inserted here in .class file of Child
    System.out.println("S2");
  }
}

And your Parent class is converted to following:

Parent() 
{
    super();//Constructor of Object class
    System.out.println("S1");
}

That's why your output is showing as:

S1 //output from constructor of super class Parent
S2 //output from constructor of child Class Child

Inheritance and constructors in Java, Inheritance and constructors in Java. Last Updated: 17-07-2018. In Java, constructor of base class with no argument gets automatically called in derived class� Like C++, Java would also benefit from syntax that permits constructor inheritance. – Derek Mahar Mar 28 '11 at 5:26 If you have a private final int foo; in the superclass Super , you can not assign a value to foo in the inherited Constructor in Son because its private in Super .

Java doc says :

A subclass inherits all the members (fields, methods, and nested classes) from its superclass. Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass.

If you don't declare a constructor of any type, a default is added.

If you don't call any other constructor in the first line of your subclass, a call to super() is made.

Java Constructor Inheritance, Suppose constructors were inherited then because every class eventually derives from Object, every class would end up with a� Java doc says : A subclass inherits all the members (fields, methods, and nested classes) from its superclass. Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass. If you don't declare a constructor of any type, a default is added.

Constructor are not inherited.

Super class constructor are not inherited in derived class.

Is there any possibility to create 2 constructors without parameters and have only Child constructor on result without base constructor.

No, Its not possible In Java every derived class constructor call super class constructor. If you not add it call no argument constructor.

public SuperClass() {
   ...
}

public DerivedClass() {
  //Compiler here call no argument constructor of Super class.
}

Inheritance (The Java™ Tutorials > Learning the Java Language , A subclass inherits all the members (fields, methods, and nested classes) from its superclass. Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass. Java Constructors. A constructor in Java is a special method that is used to initialize objects. The constructor is called when an object of a class is created. It can be used to set initial values for object attributes:

A constructor will always call its superclass constructor unless an explicit constructor has been defined. From the Java Language Specification:

If a constructor body does not begin with an explicit constructor invocation and the constructor being declared is not part of the primordial class Object, then the constructor body implicitly begins with a superclass constructor invocation "super();", an invocation of the constructor of its direct superclass that takes no arguments.

Inheritance and Constructors — Java Review, In Java you can put a call to the parent constructor as the first line in a subclass constructor to initialize inherited fields. public class Person { private String name; � We understood the various scenarios for Java constructor inheritance. In summary, when you create an object of a sub-class, Java implicitly invokes the base class constructor. If there is no constructor in the base class, Java supplies a default no arguments constructor in the base class and inserts a call to this constructor.

You write:

It shows that Child inherited constructor.

Constructors can not be inherited. Classes can be inherited, so Child does not inherit any constructor. Child inherits class Parent. Parent inherits class Object. When you call the Child constructor, automatically an Object constructor is called and then a Parent constructor, before the code of the Child constructor is run.

This why you get this result:

S1
S2

Inheritance in Java Programming with examples, Constructors and Inheritance. constructor of sub class is invoked when we create the object of subclass, it by default invokes the default constructor of super class. A Java constructor cannot be abstract, static, final, and synchronized; Note: We can use access modifiers while declaring a constructor. It controls the object creation. In other words, we can have private, protected, public or default constructor in Java. Types of Java constructors. There are two types of constructors in Java:

Java Inheritance, When creating a Constructor method in a derived class (subclass), you should call the base Duration: 4:50 Posted: 1 May 2018 Constructor is a block of code that allows you to create an object of class and has same name as class with no explicit return type. Whenever a class (child class) extends another class (parent class), the sub class inherits state and behavior in the form of variables and methods from its super class but it does not inherit constructor of super class because of following reasons:

Inheritance Part 3: Constructors (Java), The video looks at the roll constructors play in inheritance. It shows how only one constructor Duration: 11:10 Posted: 7 Feb 2017 Subclass Constructors. The following example illustrates how to use the super keyword to invoke a superclass's constructor. Recall from the Bicycle example that MountainBike is a subclass of Bicycle. Here is the MountainBike (subclass) constructor that calls the superclass constructor and then adds initialization code of its own:

Java - Inheritance, Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass. The super keyword.