Question: Can We Have More Than One Constructor In A Class?

Can you have 2 constructors in Java?

There can be multiple constructors in a class.

However, the parameter list of the constructors should not be same.

This is known as constructor overloading..

Can a constructor be private?

Yes, we can declare a constructor as private. If we declare a constructor as private we are not able to create an object of a class. We can use this private constructor in the Singleton Design Pattern.

Why do we create constructors in Java?

The purpose of constructor is to initialize the object of a class while the purpose of a method is to perform a task by executing java code. Constructors cannot be abstract, final, static and synchronised while methods can be. Constructors do not have return types while methods do.

What is a overloaded constructor?

Constructor overloading is a concept of having more than one constructor with different parameters list, in such a way so that each constructor performs a different task. For e.g. Vector class has 4 types of constructors.

Can constructor be inherited?

Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass.

Can you have a class without constructors?

Java doesn’t require a constructor when we create a class. … The compiler automatically provides a public no-argument constructor for any class without constructors. This is called the default constructor.

Can abstract class have a constructor?

The constructor inside the abstract class can only be called during constructor chaining i.e. when we create an instance of sub-classes. This is also one of the reasons abstract class can have a constructor.

Why do we use constructor overloading?

If we want to have different ways of initializing an object using different number of parameters, then we must do constructor overloading as we do method overloading when we want different definitions of a method based on different parameters.

How many constructors can a class have?

A class can have any number of constructors. If a class have more than one constructor, we call it as the constructor is overloaded.

Can we have more than one constructor in a class in C++?

C++ allows more than one constructor. The other constructors must have different parameters. Additionally constructors which contain parameters which are given default values, must adhere to the restriction that not all parameters are given a default value.

Can a class have multiple constructors Python?

Python does not support explicit multiple constructors, yet there are some ways using which the multiple constructors can be achieved. If multiple __init__ methods are written for the same class, then the latest one overwrites all the previous constructors.

How many default constructors can a class have?

one default constructorA class can only have one default constructor.

Can we override private methods?

No, we cannot override private or static methods in Java. Private methods in Java are not visible to any other class which limits their scope to the class in which they are declared.

What is multiple constructor in a class?

A class can have multiple constructors that assign the fields in different ways. Sometimes it’s beneficial to specify every aspect of an object’s data by assigning parameters to the fields, but other times it might be appropriate to define only one or a few.

Can a class have both default constructor and parameterized constructor?

We can have any number of Parameterized Constructor in our class. In this example, I have implemented four constructors: one is default constructor and other three are parameterized.

How do you call a constructor?

No, you cannot call a constructor from a method. The only place from which you can invoke constructors using “this()” or, “super()” is the first line of another constructor. If you try to invoke constructors explicitly elsewhere, a compile time error will be generated.

Can you have two constructors?

A class can have multiple constructors, as long as their signature (the parameters they take) are not the same. You can define as many constructors as you need. When a Java class contains multiple constructors, we say that the constructor is overloaded (comes in multiple versions).

Can constructor be overloaded?

Yes! Java supports constructor overloading. In constructor loading, we create multiple constructors with the same name but with different parameters types or with different no of parameters.

Can a class have two constructors C++?

In C++, We can have more than one constructor in a class with same name, as long as each has a different list of arguments. This concept is known as Constructor Overloading and is quite similar to function overloading.

Can private constructor class inherited?

What is Private Constructor? … If a class has one or more private constructor and no public constructor then other classes are not allowed to create instance of this class; this means you can neither create the object of the class nor can it be inherited by other classes.

What is the purpose of private constructor?

Private constructors are used to prevent creating instances of a class when there are no instance fields or methods, such as the Math class, or when a method is called to obtain an instance of a class. If all the methods in the class are static, consider making the complete class static.