Second Short Program Java

Second Short Program Java

Perhaps no other concept is more fundamental to a programming language than that of a variable. As you may know, a variable is a named memory location that may be assigned a value by your program.

class Example2 {   
    public static void main(String args []) {
        int num; // this declares a variable called num 
        num = 100; // this assigns num the value 100 
        System.out.println("This is num: " + num); 
        num = num * 2; 
        System.out.print("The value of num * 2 is "); 



This is num: 100

The value of num * 2 is 200

This line declares an integer variable called num. Java (like most other languages) requires that variables be declared before they are used. Following is the general form of a variable declaration: type var-name; Here, type specifies the type of variable being declared, and var-name is the name of the variable. If you want to declare more than one variable of the specified type, you may use a comma-separated list of variable names. Java defines several data types, including integer, character, and floating-point. The keyword int specifies an integer type.

In the program, the line
num = 100; // this assigns num the value 100
assigns to num the value 100. In Java, the assignment operator is a single equal sign. The next line of code outputs the value of num preceded by the string “This is num:”.
System.out.println(“This is num: ” + num);
In this statement, the plus sign causes the value of num to be appended to the string that precedes it, and then the resulting string is output.