Contents

Introduction to Java

DataType and Operation

Conditional statements

Iterative statements

Nested loops

Functions

OOPs

String

Static Data members

Inherintance

Polymorphisam

Applets

AWT

MultiThreading

I/o

Exception Handling

Collection FrameWork

Contents

Introduction to Java

DataType and Operation

Conditional statements

Iterative statements

Nested loops

Functions

OOPs

String

Static Data members

Inherintance

Polymorphisam

Applets

AWT

MultiThreading

I/o

Exception Handling

Collection FrameWork

Constructors

Constructor Overloading

Defining multiple constructors in class is called as constructor overloading.
Only precaution to be taken is that

No of arguments or
Type of arguments or
Sequence of arguments must be different

An appropriate constructor will be called depending on no of argument or type of argument or sequence of arguments that are passed while creating an object.
Note: The advantage of constructor overloading is that we can create objects of same class in different ways.

Syntax

[AccessSpecifier] ClassName(datatype arg1,datatype arg2,...)
{
    Statements
    ----------
    ----------
}

#Program to create 2 rectangles a and b of size 5x7 and 10x20.Display area, perimeter of a and area of b.

Design a class Rectangle

Data members

Length
Breadth

Member Functions

Area()
Perimeter()

  class rectangle 
  {
    private int length,breadth;
    public void area()
    {
        int a=length*breadth;
        System.out.println("Area is "+a);
    }
    public void perimeter()
    {
        int p=2*(length+breadth);
        System.out.println("perimerter is"+p);
    }
    public void setdimension(int m,int n)
    {
        length=m;
        breadth=n;
    }
  }
  class demo
  {
    public static void main(String args[])
    {
        rectangle a, b ;
        a = new rectangle();
        b=new rectangle();
        a.setdimension(5,7);
        b.setdimension(10,20);
        a.area();
        a.perimeter();
        b.area();
    }
  }

Area is 35
Perimeter is 24
Area is 200

#Program to create 2 students a ( rollno=4117 name=Amit Jain ) , b ( name=Seeta Rathi rollno=3012 ) . Display their information.

Design a class Student

Data members

rollno
name

Member Functions

showdata()
setdata(rn,nm)
setdata(nm,rn)

  class Student 
  {
    private int rollno;
    private String name;
    public void showData()
    {
        System.out.println("RollNo is "+rollno);
        System.out.println("Name is "+name);
    }
    public void setData(int rn,String nm)
    {
        rollno = rn;
        name = nm;
    }
    public void setData(String nm,int rn)
    {
        rollno = rn;
        name = nm ;
    }
  }
  class demo
  {
    public static void main(String args[])
    {
        Student a = new Student();
        Student b = new Student();
        a.setData(4117,"Amit Jain");
        b.setData("Seeta Rathi",3012);
        a.showData();
        b.showData();
    }
  }

RollNo is 4117
Name is Amit Jain 
RollNo is 3012
Name is Seeta Rathi

#Program to create 3 circle a ,b(radius=5) and c( radius=2.5 ) .Display area.

Design a class Circle

Data members

radius

Member Functions

Area()
Circle()
Circle(n) -int
Circle(n) -double

  class Circle
  {
    private double R;
    public void area()
    {
        double A=3.14*R*R;
        System.out.println("Area is "+A);
    }
    public void Circle()
    {
        R = 1;
    }
    public void Circle(int n)
    {
        R = n;
    }
    public void Circle(double n)
    {
        R = n;
    }
  }
  class demo
  {
    public static void main(String args[])
    {
        Circle a = new Circle();
        Circle b = new Circle(5);
        Circle c = new Circle(2.5);
        a.area();
        b.area();
        c.area();
    }
  }

Area is 3.14 
Area is 78.5 
Area is 19.625

CCITcoder

Introduction to Java

DataType and Operation

Conditional statements

Iterative statements

Functions

OOPs

String

Static Data members

Inherintance

Polymorphisam

Applets

AWT

MultiThreading

I/o

Exception Handling

Collection FrameWork

Introduction to Java

DataType and Operation

Conditional statements

Iterative statements

Functions

OOPs

String

Static Data members

Inherintance

Polymorphisam

Applets

AWT

MultiThreading

I/o

Exception Handling

Collection FrameWork

Constructors

Constructor Overloading