Java Scanner Class Flashcards

Java Scanner Class Overview

• Scanner scnr = new Scanner(System.in); initializes a new Scanner object named scnr for reading input from the console.
• fullName = scnr.nextLine(); captures the next line of input as a String, storing it in the variable fullName.
• age = scnr.nextInt(); retrieves the next integer input from the user and assigns it to the variable age.

Key Concepts

• The Scanner class is a part of java.util package and it simplifies keyboard input handling in Java applications.
• System.in serves as the standard input stream connected to the console, allowing interaction via keyboard input.
• The operator new is used to create and instantiate new objects in Java, allocating memory on the heap for those objects.

Scanner Functionality

• The next() method reads the next input token as a String, which is ideal for single word inputs, separating them based on whitespace.
• A package in Java is a namespace that organizes a set of related classes and interfaces, facilitating code management.

Basic Structure

• The snippet public class first { public static void main(String[] args) { illustrates the structure for defining a new class and the entry point of a Java program.
• To utilize the Scanner class in a program, the statement import java.util.Scanner; must be included at the beginning of the code to import the required class.

Additional Information

• A Scanner instance is necessary for scanning various types of input, including Strings, integers, and more, through specific methods provided by the class.
• Understanding memory allocation and class structure is crucial for effective Java programming, particularly when working with input handling.