CJ-10: Print a message 5 times-While loop

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

***********************************************************************************************

import java.io.*;

class loop1

{

public static void main(String args[])

{

int i=0;

while(i<=4)

{

  System.out.println("Welcome to JAVA");

  i++;

}

}

}

=========================================================================

Output :

Welcome to JAVA

Welcome to JAVA

Welcome to JAVA

Welcome to JAVA

Welcome to JAVA


Refar Print a message 5 times-Do While loop and Print a message 5 times-For loop also.

CJ-9: Odd or Even checking

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

***********************************************************************************************

import java.io.*;

class oddeven

{

public static void main(String arg[])

{

   int number;

   try

   {

      DataInputStream x=new DataInputStream(System.in);

      System.out.println("Enter a number :");

      number=Integer.parseInt(x.readLine());

      if(number%2==0)

      {

System.out.println("Number is Even");

      }

         else

         {

    System.out.println("Number is Odd");

}

    }

catch(Exception e)

{

}

}

}

=========================================================================

Output :

Enter a number :

7

Number is Odd

CJ-8: Print Day according to number

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

***********************************************************************************************

import java.io.*;
class day
{
public static void main(String args[])
{
   int n;
   try
   {
DataInputStream x=new DataInputStream(System.in);
System.out.println("Enter a number upto 7");
n=Integer.parseInt(x.readLine());
  switch(n)
  {
                case 1:
System.out.println("Sunday");
break;
case 2:
System.out.println("Monday");
break;
case 3:
System.out.println("Tuesday");
break;
case 4:
System.out.println("Wednesday");
break;
case 5:
System.out.println("Thursday");
break;
case 6:
System.out.println("Friday");
break;
case 7:
System.out.println("Saturday");
break;
default:
System.out.println("Invalid Number");
break;
}
}
   catch(Exception e)
   {
   }
}
}

=========================================================================

Output :

Enter a number below 8

7

Saturday

CJ-7: Check whether eligible for vote

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

***********************************************************************************************

import java.io.*;

class chk

{

public static void main(String args[])

{

int age;

try

{

   DataInputStream x=new DataInputStream(System.in);

   System.out.println("Enter age :");

   age=Integer.parseInt(x.readLine());

if(age>=18)

{

System.out.println("Eligible for vote");

}

else

{

System.out.println("Not Eligible for vote");

}

}

catch(Exception e)

{

}

}

}

========================================================================= 

Output : 

Enter age :

20

Eligible for vote.

CJ-6 : Four Calculations-Floating no

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

***********************************************************************************************

import java.io.*;

class math1

{

public static void main(String args[])

{

 float a,b,result;

 try

 {

  DataInputStream x=new DataInputStream(System.in);

  System.out.println("Enter the first number :");

  a=Float.parseFloat(x.readLine());

  System.out.println("Enter the second number :");

  b=Float.parseFloat(x.readLine());

   result=a+b;

   System.out.println("Addition = "+result);

   result=a-b;

   System.out.println("Subtraction = "+result);

   result=a*b;

   System.out.println("Multiplication = "+result);

   result=a/b;

   System.out.println("Division = "+result);

 }

 catch(Exception e)

 {

 }

}

}

========================================================================= 

Output : 

Enter the first number

12.24

Enter the second number

12.28

Addition=24.52

Subtraction =-0.03999996

Multiplication =150.30719

Division=0.99674267

Refer Four Calculations-Floating no also.

CJ-5 : Four Calculations-Integer no

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

***********************************************************************************************

import java.io.*;

class math

{

public static void main(String args[])

{

int a,b,result;

try

{

DataInputStream x=new DataInputStream(System.in);

System.out.println("Enter the first number :");

a=Integer.parseInt(x.readLine());

System.out.println("Enter the second number :");

b=Integer.parseInt(x.readLine());

result=a+b;

System.out.println("Addition = "+result);

result=a-b;

System.out.println("Subtraction = "+result);

result=a*b;

System.out.println("Multiplication = "+result);

result=a/b;

System.out.println("Division = "+result);

}

catch(Exception e)

{

}

}

}

========================================================================= 

Output : 

Enter the first number

8

Enter the second number

4

Addition=12

Subtraction =4

Multiplication =32

Division=2

Refer Four Calculations-Floating no also.

CJ-4 : Sum(user defined values)

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

*********************************************************************************************
Refer Sum(predefined values) also.
*********************************************************************************************
import java.io.*;

class Adduser 

{

public static void main(String args[]) 

{   

     int a,b,sum;

     try

{

DataInputStream x=new DataInputStream(System.in);

System.out.println("Enter two numbers :");

a=Integer.parseInt(x.readLine());

b=Integer.parseInt(x.readLine());

sum=a+b;

System.out.println("Addition= "+sum);

}

   catch(Exception e)

   {

   }

}

}

========================================================================= 

Output : 

Enter two numbers :

30

20

Addition=50.

CJ-3 : Sum(predefined values)

Type the programs in NOTEPAD or DOS prompt itself, for Consol Application.
Type in NETBEANS or ECLIPSE for Window Application.
Here after , I am just typing the programs only..to know more about it , refer

Introduction to JAVA 

before doing any JAVA Programs.

************************************************************************************
Refer Sum(user defined values) also.
************************************************************************************

class Add 

{

public static void main(String args[]) 

{   

     int a,b,c;

     a=20;

     b=40;

     c=a+b;

     System.out.println("Addition="+c);

}

}

=========================================================================

Output : Addition=60.

CJ-2 : Welcome Program-Window Application

For a complete list, click JAVA

Refer Introduction to JAVA before going through your first program.

And for theory part , refer "Some Theory Part in JAVA"

=========================================================================
class firstprogram
{
public static void main(String args[ ])
{
System.out.println("Hai...Welcome...");
}
}

=========================================================================

• Here, firstprogram is the program name.(See, class firstprogram ).The name after declaring the class , is the program name.We have to use the same name , while saving.
• Also note the capital letters of the words String and System. They are case sensitive.

Instead of typing the program  in NOTEPAD or DOS prompt , here , we are using some softwares like NETBEANS or ECLIPSE etc..

========================================================================= 

(A) : Familier with NETBEANS platform:

Download NetBeans IDE 

Download NetBeans from here for free. (You need JDK or Java Development Kit for installing NetBeans . If you have no Java platform on your system , download from here (which contains JDK+NetBeans ) .

When clicking this , we get  :

We will get a window as shown below :

Click ; File--> New Project.

Then we can see,

Select JAVA from Categories;  and JAVA APPLICATION from Projects.

Click , Next .

Then , another window will appear as : 

Give a project name , and click Finish.

Then we can see the NetBeans IDE for typing the program.It will look like ;

In our program , we need to type the last println statement only.

The sentenses like /**/  does not tken by the Compiler.So, no need to bother about the extra sentenses you see there.

After typing the println statement to display "Hai....Welcome..." , we have to run it.

right click on the page , and select Run the File , from the drop down menu( or , select from the main menu....or , you can use ShiftF6).

The output will displayed in the bottom....as ; 

=========================================================================

(B) : Familier with ECLIPSE platform:

When clicking this , we get  :  

After giving the details as done before , we can see the Eclipse IDE for typing the program.
I just did the programs and you can see the output there.
(It is also more or less same as NETBEANS , so i just skip the steps for taking the Eclipse IDE here....)

CJ-1 : Welcome Program-Consol Application

For a complete list, click JAVA

Refer Introduction to JAVA before going through your first program.

And for theory part , refer "Some Theory Part in JAVA"

=========================================================================
class firstprogram
{
public static void main(String args[ ])
{
System.out.println("Hai...Welcome...");
}
}

=========================================================================

• Here, firstprogram is the program name.(See, class firstprogram ).The name after declaring the class , is the program name.We have to use the same name , while saving.
• Also note the capital letters of the words String and System. They are case sensitive.

Type this program in NOTEPAD.

Then , save the program in the same folder , in which the JAVA software is installed.

Here, I installed the JAVA in C disk , jdk 1.3 is the version and bin is the directory.

So , the path is C:\jdk1.3\bin .

(Note the path of the JAVA of your computer.So dont blindly follow the path I described :)

Note the path in above picture.

And it saved as firstprogram.java .

Next, open DOS .

Choose the path in which JAVA is installed..

To do this , follow the steps given.

1. Type cd\ and press entre . Then we get C:\>
2. Now choose the directory in which JAVA is installed. Here , my path is jdk 1.3\bin. So, type cd jdk1.3\bin .Then we get , C:\jdk1.3\bin>
3. Now , compile the program , by typing, javac followed by program name. Here, our program name is firstprogram . Dont forget to put the extension .JAVA  . That is we have to type , javac firstprogram.java
4. Then Run the program by typing , java followed by program name . That is , java firstprogram.

Then we get the result : Hai...Welcome...

 See the picture below : 

(You can save the JAVA programs in any of the Directory you want , but you havr to give the JAVA installed directory thereafter , using the path command.That is ,

1. First choose the program directory in DOS prompt.
2. Then choose the JAVA installed directory , followed by path command.

That is , after giving the location of your program path , type : 

path jdk1.3\bin>

Then compile and run the program.

How to use DOS platform to type\save\edit JAVA:

1. Type cd\ and press entre . Then we get C:\>
2. Now choose the directory in which JAVA is installed. Here , my path is jdk 1.3\bin. So, type cd jdk1.3\bin .Then we get , C:\jdk1.3\bin>
3. Now type , edit followed by the program name.java ( Here, edit firstprogram.java )

Then we can see ;

We can edit the same NOTEPAD program in DOS prompt too...

If we give a new name , then we can type new program in that DOS prompt, then SAVE it in the JAVA directory as told before .

File--> Exit will return to the normal DOS prompt.