scanner in java

Scanner in java

 To understand Scanner in java and start using it we have to know some principles

• The Scanner class is used to get user input
• Scanner is found in the java.util package
• To use scanner we have to make an object from scanner class

In other we if we want to use scanner we have to make and object for it , and to make and object for it first we have to import it first , so let us to do this in a code

1/ import scanner 

    import java.util.*;   Or
    import java.util.Scanner;

2/ make object for scanner

    as we know the rule to make an object for any class is 

    class_name object_name = new class_name();

    

    and to create scanner object we can do it as bellow

    Scanner scan = new Scanner(System.in);
    

    scan is the object name , system.in to define that we will read some values form the user

3/ use the scanner to get variable's value from the user

    we can define the variable and then get it's value from the user as bellow

    EG :

        int num;
        num = scan.nextInt();

    or define a variable and get it's value from the user in one line as bellow

    EG : 

        int num = scan.nextInt();

    *Note

 

     we can define (byte , short , long , int , double , float , boolean) with scanner as bellow

 

    byte variable_name = scan.nextByte();

    short variable_name = scan.nextShort();

    int variable_name = scan.nextInt();

    long variable_name = scan.nextLong();

 

    double variable_name = scan.nextDouble();   

    float variable_name = scan.nextFloat(); 

 

    boolean variable_name = scan.nextBoolean(); 

 

and we can (define char , string ) variables as bellow 

      

    Char

 

    char variable_name = scan.next().charAt(0);  Or  
    char variable_name = scan.nextLine().charAt(0);

 

 

    String

 

    String variable_name = scan.nextLine(); Or

    String variable_name = scan.next();