In my opinion, there is only a syntax difference between parameterized constructors and setter function in JAVA. Both would be used to initialize the class variables with user-defined values.
In parameterized constructors, all the class variables can be initialized within one function (constructor) which is automatically invoked when a user creates an object of that class.
On the other hand, while using a Setter function. Each class variable should have its own setter method which needs to be invoked for each variable of that class.
Getter function is used to read/access the class variables. There are two methods to access/read a class variable using a return statement or without the return statement.
ClassA
/**
*
*/
package GetterSetter;
/**
* @author ashok.kumar
*
*/
public class ClassA
{
int roll;
String name;
public ClassA(int x, String y)
{
roll=x;
name=y;
}
}
ClassB
/**
*
*/
package GetterSetter;
/**
* @author ashok.kumar
*
*/
public class ClassB
{
int rollB;
String nameB;
// Setter function for 'rollB'
void setrollB(int x)
{
rollB=x;
}
// Getter function for 'rollB'
void getrollB()
{
System.out.println(rollB);
}
// Setter function for 'nameB'
void setnameB(String y)
{
nameB=y;
}
// Getter function for 'nameB' via return statement.
String getnameB()
{
return nameB;
}
}
mainClass
/**
*
*/
package GetterSetter;
/**
* @author ashok.kumar
*
*/
public class mainClass {
public static void main(String[] args) {
ClassA objA=new ClassA(10,"Rambo");
System.out.println("Value of ClassA object");
System.out.println(objA.roll + " " + objA.name);
objA=new ClassA(20,"Ramesh");
System.out.println(objA.roll + " " + objA.name);
ClassB objB=new ClassB();
objB.setrollB(20);
objB.setnameB("Ajay");
System.out.println("\nValue of ClassB object");
objB.getrollB(); // First method to read/access Class variable.
System.out.println(objB.getnameB()); // Alternate method to read/access Class variable.
objB.setrollB(30);
objB.setnameB("Rajan");
objB.getrollB();
System.out.println(objB.getnameB());
objB.setrollB(40);
objB.setnameB("Sonu");
objB.getrollB();
System.out.println(objB.getnameB());
}
}
Console Output
Value of ClassA object
10 Rambo
20 Ramesh
Value of ClassB object
20
Ajay
30
Rajan
40
Sonu
