Question

Using constructor overloading method, create 3 constructors with different
parameter lists to display:
 the Roll No. and Name in constructor 1,
 Roll No., Name and Age in constructor 2
 Roll No., Name, Age and Address in constructor 3
 Use Display () method to display the output

Answer 1

Explanation:

class StudentData { private int stuID; private String stuName; private int stuAge; StudentData() { //Default constructor stuID = 100; stuName = "New Student"; stuAge = 18; } StudentData(int num1, String str, int num2) { //Parameterized constructor stuID = num1; stuName = str; stuAge = num2; } //Getter and setter methods public int getStuID() { return stuID; } public void setStuID(int stuID) { this.stuID = stuID; } public String getStuName() { return stuName; } public void setStuName(String stuName) { this.stuName = stuName; } public int getStuAge() { return stuAge; } public void setStuAge(int stuAge) { this.stuAge = stuAge; } public static void main(String args[]) { //This object creation would call the default constructor StudentData myobj = new StudentData(); System.out.println("Student Name is: "+myobj.getStuName()); System.out.println("Student Age is: "+myobj.getStuAge()); System.out.println("Student ID is: "+myobj.getStuID()); /*This object creation would call the parameterized * constructor StudentData(int, String, int)*/ StudentData myobj2 = new StudentData(555, "Chaitanya", 25); System.out.println("Student Name is: "+myobj2.getStuName()); System.out.println("Student Age is: "+myobj2.getStuAge()); System.out.println("Student ID is: "+myobj2.getStuID()); } }