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Thread: New to Java, could you explain something to me?

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    Default New to Java, could you explain something to me?

    Hi, I am new to java, and I have been following some youtube video tutorials and I'm not clear on something, so could you please explain it.

    Here is the code:

    import java.util.Scanner;
    public class GetUserInput {
    	public static void main(String args[]){
    	Scanner number = new Scanner(System.in);
    	System.out.println(number.nextLine());
    	}
    }

    On the line
    Scanner number = new Scanner(System.in);
    I am creating a variable called number of the Scanner class, and then I am assigning it something, this is what I'm confused with. I know the new keyword creates an instance of a class but I dont know what is being assigned to my number variable?

    Thanks.


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    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: New to Java, could you explain something to me?

    I recommend you read through the basic tutorials, especially this section: Lesson: Classes and Objects (The Java™ Tutorials > Learning the Java Language)
    Useful links: How to Ask Questions the Smart Way | Use Code Tags | Java Tutorials
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    Default Re: New to Java, could you explain something to me?

    new Scanner(System.in) is a call to the constructor for a Scanner object. What you're doing is creating a new Scanner object then assigning that object to the variable number (for a more verbose answer, the variable number "references" or "points to" that Scanner object that was created).

    The System.in is a parameter of the Scanner constructor. It's the stdin stream (i.e. the stream that console input is read from). It's a static field found in the class System, and the field's name is in.

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    Default Re: New to Java, could you explain something to me?

    Thanks for replying. I have a few questions:

    1. So, in
    Scanner number = new Scanner(System.in);
    I am assigning number the reference to a Scanner object?

    2. With that being said, that means when I refer to the number variable I am using the scanner object?

    3. And then we are giving the Scanner object a parameter of our keyboard input, so when it comes to the line
    System.out.println(number.nextLine());
    it displays the values I type it, althought it pauses and waits until I type in values because none have yet been entered?
    Last edited by TP-Oreilly; September 16th, 2011 at 12:45 PM.

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    Default Re: New to Java, could you explain something to me?

    If I'm right could you put just a simple yes

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    Default Re: New to Java, could you explain something to me?

    You are correct. Congrats.

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    Default Re: New to Java, could you explain something to me?

    Thanks

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