Constructor is a special method in Java that is used to initialize an object. There are two types of constructors: default (no-arg) constructors that have no parameters, and parameterized constructors that allow passing parameters to set object attribute values. Constructors can be overloaded to support different initialization scenarios. They are invoked during object creation to construct and provide initial values for the object's attributes.

1. CONSTRUCTOR
S.G.V.P.Gunasekara - 2015238
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2. Constructor
Constructor in java is a special type of method that is used to initialize the
object.
Java constructor is invoked at the time of object creation. It constructsthe
values i.e. provides data for the object that is why it is known as
constructor.
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3. Rules for creating java constructor
There are basically two rules defined for the constructor.
1. Constructor name must be same as its classname
2. Constructor must have no explicit returntype
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4. Types of java constructors
There are two types of constructors:
1. Default constructor (no-arg constructor)
2. Parameterizedconstructor
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5. Default constructor
class. It will be invoked at the
A constructor that have no parameter is known as defaultconstructor.
Syntax of default constructor:
<class_name>(){}
Example of default constructor
In this example, we are creating the no-arg constructor in theBike
time of object creation.
class Bike1{
Bike1(){
System.out.println(&quot;Bike is created&quot;)
;}
public static void main(Stringargs[]){
Bike1 b=new Bike1();
}
}
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6. Parameterized constructor
A constructor that have parameters is known as parameterizedconstructor.
Why use parameterized constructor?
Parameterized constructor is used to provide different values to
the distinct objects.
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7.  Example of parameterized constructor
In this example, we have created the constructor of Student class that have two parameters.
We can have any number of parameters in the constructor.
class Student4{
int id;
String name;
Student4(int i,String n){
id = i;
name = n;
}
void display(){System.out.println(id+&quot; &quot;+name);}
public static void main(String args[]){
Student4 s1 = new Student4(111,&quot;Karan&quot;);
Student4 s2 = new Student4(222,&quot;Aryan&quot;);
s1.display();
s2.display();
}
}
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8. Output:
111 Karan
222 Aryan
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9. Constructor overloading
Like other methods in java constructor can be overloaded i.e. we can
create asmany constructors in our class asdesired. Number of
constructors depends on the information about attributes of an objectwe
have while creating objects.
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10. example: constructor overloading example:
classLanguage{
String name;
Language() {
System.out.println("Constructor methodcalled.");
}
Language(String t) {
name = t;
}
public static void main(String[] args) {
Language cpp = new Language();
Language java = new Language("Java");
cpp.setName("C++");
java.getName();
cpp.getName();
}
void setName(String t) {
name = t;
}
void getName() {
System.out.println("Language name: " + name);
}
}
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11. Output:
Constructor method called.
Language name: java
Language name:c++
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