Write a program for calculating area and perimeter of a rectangle
If you are a newbie in Java programming then our
tutorials and examples will be helpful in understanding Java programming in the
most simplest way. Here after reading this lesson, you will be able to write
program for calculating the area and perimeter of a rectangle.
First of all create a class named RecArea under
Java.io package. Now define two integer variable 'l' and 'w'. As
the program will be based on keyboard numerical input, it is important for every
programmer to use correct data without any mistake. In this case the exception
methods like try/catch mechanism helps in detecting user input errors. So
before starting the functional code, enclosed it with try clause so that
any error in the statement causes the execution of the catch clauses.
Now create an abstract buffer class which is the super
class of all classes and represents a stream of input bytes. The
InputSreamReader reads the character stream and stores it in the buffer class.
Now use parseInt for both length and width of the rectangle. This
is an instance of class method and is used to convert a string to an integer.
Define the area as l*w and perimeter as 2*(l+w) and in the end use the catch
exception.
Now compile and run the program and input the value as
you see the message and get the ultimate result. If you find any kind of error,
then check the whole program again.
Here is the code of the program:
import java.io.*;
class RecArea
{
public static void main(String[] args)
{
int l=0;
int w=0;
try{
BufferedReader br1 = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter length of rectangle : ");
l = Integer.parseInt(br1.readLine());
System.out.println("Enter width of rectangle : ");
w = Integer.parseInt(br1.readLine());
int area = l*w;
System.out.println("Area of Rectangle : "+area);
int perimiter = 2*(l+w);
System.out.println("Perimeter: " + perimiter);
}catch(Exception e){System.out.println("Error : "+e);}
}
}
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Current Comments
4 comments so far (post your own) View All Comments Latest 10 Comments:This site has a good tutorial. i am beginner in java.
i have learn very good tips in this site. i am a php developer.
Posted by Govind on Friday, 08.31.07 @ 18:36pm | #24621
this code snippet is awesome
i can get the clear idea of user input functions
but it could be better if you would show different method of implementing the same
than
Posted by ramesh on Saturday, 06.2.07 @ 13:44pm | #18011
Hi,
Dear Karthik!
I got your problem [BufferedReader br1 = new BufferedReader(new InputStreamReader(System.in))]. You visit the following url for better understanding to this.
You can also take data from the keyboard through command line.
For example:
int a = Integer.parseInt(args[0]), int b = Integer.parseInt(args[1]) and so on.]
Read more: [url = http://www.roseindia.net/java/example/java/io/ReadStandardIO.shtml] BufferedReader class[/url]
vinod kumar
Posted by vinod kumar on Tuesday, 03.6.07 @ 19:08pm | #10862
I am lil bit confused at the usage of
BufferedReader br1 = new BufferedReader(new InputStreamReader(System.in))
is there any other possibility with out using this?
Posted by karthik on Monday, 02.26.07 @ 14:11pm | #9650