what is constructor in java and types of constructors in java
In Java, a constructor is a special type of method that is used to initialize objects of a class. It is called automatically when an object is created, and its purpose is to ensure that the object is in a valid and usable state. Constructors have the same name as the class and do not have a return type, not even void.
There are three types of constructors in Java:
- Default Constructor: A default constructor is provided by Java if you do not explicitly define any constructor in your class. It takes no arguments and has an empty body. Its purpose is to initialize the object with default values.
For example:
public class MyClass {
// Default constructor
public MyClass() {
// Initialization code
}
}
- Parameterized Constructor: A parameterized constructor is defined with one or more parameters. It allows you to initialize the object with specific values passed as arguments during object creation.
For example:
public class MyClass {
private int value;
// Parameterized constructor
public MyClass(int value) {
this.value = value;
}
}
- Copy Constructor: A copy constructor is used to create a new object by copying the values of another object of the same class. It helps in creating a deep copy of the object, ensuring that the new object has its own copies of the data rather than just references to the existing object.
For example:
public class MyClass {
private int value;
// Copy constructor
public MyClass(MyClass other) {
this.value = other.value;
}
}