Get input keyboard java

Java how to get keyboard input in java

Here, we used the method to get the int type of the input: Output: Getting Keyboard Input Using Class in Java We can use the class to get user input in Java. To get a user input in Java, you’ll encounter several classes such as the , , and .

Get a Keyboard Input in Java

This tutorial introduces how to get a keyboard input or user input in Java. We also included example programs to help you understand this topic better.

To get a user input in Java, you’ll encounter several classes such as the Scanner , BufferedReader , and Console . We’ll use these classes for our operation as we show you the different methods you can follow.

Getting Keyboard Input Using BufferedReader in Java

In this example, we used the BufferedReader class that takes the InputStreamReader class’s instance to read a user input. Here, the readLine() method reads the user input and returns a string as a result:

import java.io.BufferedReader; import java.io.InputStreamReader; public class SimpleTesting< public static void main(String[] args) < BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); System.out.println("Enter Input : "); try < String s = br.readLine(); System.out.println(s); >catch(Exception e) < System.out.println(e); >> > 

Getting Keyboard Input Using Scanner Class in Java

The Scanner class is one of the simplest ways to get user input in Java. This class provides several built-in methods to get the input of various types like int and float. Here, we used the nextInt() method to get the int type of the input:

import java.util.Scanner; public class SimpleTesting < public static void main(String[] args) < System.out.println("Enter Input : "); Scanner scanner = new Scanner(System.in); int a = scanner.nextInt(); System.out.println(a); scanner.close(); >> 

Getting Keyboard Input Using Console Class in Java

We can use the Console class to get user input in Java. This class belongs to the java.io package and provides the readLine() method to read user input from the console. See the example below:

import java.io.Console; public class Main < public static void main(String[] args) < Console console = System.console(); String str = console.readLine("Enter Input : "); System.out.println(str); >> 

Getting Keyboard Input Using command-line arguments in Java

In Java, command-line arguments are the arguments that are passed during program execution. The main() method of the program has a string-type parameter that holds the input supplied from the terminal. Remember to get the command-line argument to pass them during program execution and that the type of input is always a string type.

public class SimpleTesting< public static void main(String[] args) < if(args.length>0) < System.out.println("User Input"); for (int i = 0; i < args.length; i++) < System.out.println(args[i]); >>else System.out.println("No Input Found"); > > 

Run the code and pass the keyboard input as command-line arguments.

java SimpleTesting Hello DelftStack 

User Input Hello DelftStack 

Java Scanner

JTextField — Getting Keyboard Input, Previous: https://youtu.be/IlFRRy25BXINext: https://youtu.be/9Ttlzmrhl3cIn this video, I’m going Duration: 18:32

Reading Input From the Keyboard in Java

Java Programming: Reading Input From the Keyboard in Java ProgrammingTopics Discussed
Duration: 5:44

Java Tutorial — 01 — Keyboard Input Using System.in.Read

Get more lessons like this at http://www.MathTutorDVD.com Learn how to read characters Duration: 14:18

04 — Java keyboard input

Demonstrates how to use a Scanner class object to input String data from the keyboard into a
Duration: 6:35

How to get direct keyboard input in java

UP DOWN LEFT and RIGHT as every character in the keyboard have a ASCII code, so you can actually check it out. Normally in Java, instead of checking if a key has been pressed you could use KeyEvents :

public void keyPressed(KeyEvent e) < int key = e.getKeyCode(); switch(key)< case KeyEvent.VK_RIGHT: System.out.println("The right arrow key is pressed"); // Other operations break; case KeyEvent.VK_LEFT: System.out.println("The left arrow key is pressed"); // Other operations break; case KeyEvent.VK_UP: System.out.println("The up arrow key is pressed"); // Other operations break; case KeyEvent.VK_DOWN: System.out.println("The down arrow key is pressed"); // Other operations break; >> 

You have more information in the documentation

(Java) How to get user input without pressing the «enter» key, So, for example, if the user has to choose between 1, 2, 3, 4, or 5 for input, when the user presses ‘2’, for example, the program reads this

Get keyboard input from user in java with the program running in background

Hey I can’t find a way to do this in core Java, but here is a github repo you may find useful. It seems to be a global key listener in Java.

Hopefully that GitHub repo helps but use it at your discretion, I’m sure you understand the potential dangers of creating something like this!

Getting keyboard input in java

This is a very broad question so I can only give a little bit of help. To get you started, you should use the basic java.util.Scanner that is used for most keyboard input readers.

You would have to import at least these two tools like this:

import java.util.Scanner; //reads input from keys import java.speech.Engine; //allows java to "speak" 

An alternative for the Scanner tool is BufferReader or KeyboardReader. However, I suggest Scanner because it is easiest to use and is built-in with java.

The rest of how to use the speaking Engine in java you can find here: https://www.geeksforgeeks.org/converting-text-speech-java/

Getting keyboard input in java, This is a very broad question so I can only give a little bit of help. To get you started, you should use the basic java.util.

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Get a Keyboard Input in Java

1. Getting Keyboard Input Using BufferedReader in Java
2. Getting Keyboard Input Using Scanner Class in Java
3. Getting Keyboard Input Using Console Class in Java
4. Getting Keyboard Input Using command-line arguments in Java

This tutorial introduces how to get a keyboard input or user input in Java. We also included example programs to help you understand this topic better.

To get a user input in Java, you’ll encounter several classes such as the Scanner , BufferedReader , and Console . We’ll use these classes for our operation as we show you the different methods you can follow.

Getting Keyboard Input Using BufferedReader in Java

In this example, we used the BufferedReader class that takes the InputStreamReader class’s instance to read a user input. Here, the readLine() method reads the user input and returns a string as a result:

import java.io.BufferedReader; import java.io.InputStreamReader; public class SimpleTesting  public static void main(String[] args)   BufferedReader br = new BufferedReader(new InputStreamReader(System.in));  System.out.println("Enter Input : ");  try   String s = br.readLine();  System.out.println(s);  >catch(Exception e)   System.out.println(e);  >  > > 

Getting Keyboard Input Using Scanner Class in Java

The Scanner class is one of the simplest ways to get user input in Java. This class provides several built-in methods to get the input of various types like int and float. Here, we used the nextInt() method to get the int type of the input:

import java.util.Scanner; public class SimpleTesting  public static void main(String[] args)   System.out.println("Enter Input : ");  Scanner scanner = new Scanner(System.in);  int a = scanner.nextInt();  System.out.println(a);  scanner.close();  > > 

Getting Keyboard Input Using Console Class in Java

We can use the Console class to get user input in Java. This class belongs to the java.io package and provides the readLine() method to read user input from the console. See the example below:

import java.io.Console; public class Main  public static void main(String[] args)   Console console = System.console();  String str = console.readLine("Enter Input : ");  System.out.println(str);  > > 

Getting Keyboard Input Using command-line arguments in Java

In Java, command-line arguments are the arguments that are passed during program execution. The main() method of the program has a string-type parameter that holds the input supplied from the terminal. Remember to get the command-line argument to pass them during program execution and that the type of input is always a string type.

public class SimpleTesting  public static void main(String[] args)   if(args.length>0)   System.out.println("User Input");  for (int i = 0; i  args.length; i++)   System.out.println(args[i]);  >  >else System.out.println("No Input Found");  > > 

Run the code and pass the keyboard input as command-line arguments.

java SimpleTesting Hello DelftStack 

User Input Hello DelftStack 

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Accepting keyboard input in Java is done using a Scanner object.

Consider the following statement

Scanner console = new Scanner(System.in)

This statement declares a reference variable named console. The Scanner object is associated with standard input device (System.in).

To get input from keyboard, you can call methods of Scanner class. For example in following statment nextInt() method of Scanner takes an integer and returns to variable x :

import java.util.Scanner; // Needed for Scanner class /** * This program demonstrates keyboard input. */ public class RectangleArea < public static void main(String[] args) < int length; // To hold rectangle's length. int width; // To hold rectangle's width. int area; // To hold rectangle's area // Create a Scanner object to read input. Scanner console = new Scanner(System.in); // Get length from the user. System.out.print("Enter length "); length = console.nextInt(); // Get width from the user. System.out.print("Enter width "); width = console.nextInt(); // Calculate area. area = length * width; // Display area. System.out.println("The area of rectangle is " + area); >>

Some other useful methods of Scanner class

Returns the next token as an int.

Returns the next token as a float.

Returns the next token as a long.

Finds and returns the next complete token as a string ended by a blank.

Returns the rest of the current line, excluding any line separator at the end.

import java.util.Scanner; /** * This program demonstrates various Scanner methods. */ public class ReadEmployee < public static void main(String[] args) < String name; // To hold the employee's name int age; // To hold the employee's age char gender; // To hold the employee's gender double salary; // To hold the employee's salary // Create a Scanner object to read input. Scanner console = new Scanner(System.in); // Get the employee's name System.out.print("Enter name: "); name = console.nextLine(); // Get the employee's age System.out.print("Enter age: "); age = console.nextInt(); // Get the employee's gender System.out.print("Enter gender: "); gender = console.next().charAt(0); // Get the employee's salary System.out.print("Enter salary: "); salary = console.nextDouble(); // Display the information System.out.println("Name: " + name + " Age: " + age + " Gender: " + gender + " Salary: " + salary); >>

Enter name: Alex Joseph
Enter age: 24
Enter gender: M
Enter salary: 8000
Name: Alex Joseph Age: 24 Gender: M Salary: 8000.0

• Menu
• Java Fundamentals
  • 1.1 Getting Started
  • 1.2 Creating Your First Application
  • 1.3 Parts of a Java Program
  • 1.4 Variables and Literals
  • 1.5 Primitive Data Types
  • 1.6 Arithmetic Operators
  • 1.7 Operator Precedence
  • 1.8 Type Conversion and Casting
  • Questions and Exercises
  • 2.1 Class String
  • 2.2 Objects and Reference Variables
  • 2.3 Class Math Methods
  • 2.4 String Methods
  • 2.5 Reading Keyboard Input
  • 2.6 Dialog Boxes for Input/Output
  • 3.1 The if-else Statement
  • 3.2 The if-else-if Statement
  • 3.3 Nested if Statement
  • 3.4 Logical Operators
  • 3.5 Comparing String Objects
  • 3.6 The switch Statement
  • 3.7 Conditional Operator
  • Questions and Exercises
  • 4.1 The Increment and Decrement Operators
  • 4.2 The while Loop
  • 4.3 The do-while Loop
  • 4.4 The for Loop
  • 4.5 Nested Loops
  • 4.6 The break and continue Statements
  • Questions and Exercises
  • 5.1 Introduction to Methods
  • 5.2 void Methods
  • 5.3 Passing Arguments to a Method
  • 5.4 Local Variables
  • 5.5 Returning a Value from a Method
  • Questions and Exercises
  • 6.1 Objects and Classes
  • 6.2 Designing a Class
  • 6.3 Constructors
  • 6.4 Overloading Methods
  • 6.5 UML Diagram
  • Questions and Exercises
  • 7.1 Introduction to Arrays
  • 7.2 Processing Array Elements
  • 7.3 Passing Arrays as Arguments to Methods
  • 7.4 Common Array Operations
  • 7.5 Returning Arrays from Methods
  • 7.6 String Arrays
  • 7.7 Arrays of Objects
  • 7.8 Two-Dimensional Arrays
  • 7.9 Variable-Length Argument Lists
  • 7.10 The ArrayList Class
  • Questions and Exercises
  • 8.1 Static Class Members
  • 8.2 Passing Objects as Arguments to Methods
  • 8.3 Returning Objects from Methods
  • 8.4 The toString Method
  • 8.5 The this Reference Variable
  • 8.6 Aggregation
  • 8.7 Garbage Collection
  • Questions and Exercises
  • 9.1 What Is Inheritance?
  • 9.2 Calling the Superclass Constructor
  • 9.3 Overriding Superclass Methods
  • 9.4 Protected Member
  • 9.5 Multilevel Inheritance
  • 9.6 The object Class
  • 9.7 Polymorphism
  • 9.8 Abstract Classes and Abstract Method
  • 9.9 Interfaces
  • 10.1 Introduction to File Input and Output
  • 10.2 Writing Data to Text File
  • 10.3 Reading Data from Text File
  • 10.4 Reading and Writing Premitive Data
  • 11.1 Handling Exception
  • 11.2 Try Catch Block and Multi Catch
  • 11.3 Finally Block
  • 11.4 Try with Resources
  • 11.5 Checked and Unchecked Exceptions
  • 11.6 Rethrowing and Throwing an Exception
  • 11.7 Creating Your Own Exception Classes

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