How can take input from user in java

This method is used by wrapping the System. BufferedReader; import java. IOException; import java. To read other types, we use functions like Integer. To read multiple values, we use split. Using Scanner Class This is probably the most preferred method to take input.

The main purpose of the Scanner class is to parse primitive types and strings using regular expressions, however, it is also can be used to read input from the user in the command line. Convenient methods for parsing primitives nextInt , nextFloat , … from the tokenized input. Regular expressions can be used to find tokens. The reading methods are not synchronized To see more differences, please see this article. In addition, it can be used for reading password-like input without echoing the characters entered by the user; the format string syntax can also be used like System.

Reading password without echoing the entered characters. Reading methods are synchronized. Format string syntax can be used. Recommended Articles. Article Contributed By :. Easy Normal Medium Hard Expert. Writing code in comment?

Please use ide. Load Comments. What's New. Most popular in Java. More related articles in Java. Here is a link to a useful example on how to implement the Console class. DataInputStream is primarily used for reading input as a primitive datatype, from an underlying input stream, in a machine-independent way. DataInputStream is usually used for reading binary data. It also provides convenience methods for reading certain data types.

For example, it has a method to read a UTF String which can contain any number of lines within them. However, it is a more complicated class and harder to implement so not recommended for beginners. Here is a link to a useful example how to implement a DataInputStream. Or ask user to enter two numbers and you can add, multiply, subtract, or divide those numbers and print the answers for user inputs just like a behavior of a calculator.

So there you need Scanner class. You have to import java. Scanner; and in the code you need to use. See how this differs: input. According to a String, int and a double varies same way for the rest. Don't forget the import statement at the top of your code. Also see the blog post "Scanner class and getting User Inputs". To read a line or a string, you can use a BufferedReader object combined with an InputStreamReader one as follows:.

Here, the program asks the user to enter a number. After that, the program prints the digits of the number and the sum of the digits. Just one extra detail. Note that without nextLine , the bad input will trigger the same exception repeatedly in an infinite loop.

You might want to use next instead depending on the circumstance, but know that input like this has spaces will generate multiple exceptions. This is a simple code that uses the System. This code just writes out whatever was typed. You can get rid of the while loop if you just want to take input once, and you could store answers in a character array if you so choose.

Keyboard entry using Scanner is possible, as others have posted. But in these highly graphic times it is pointless making a calculator without a graphical user interface GUI.

Note that using Scene Builder is intuitively easy and demands no additional Java skill for its event handlers that what you already may have. This is where the user enters the numbers that they want to perform functions on. Below the TextField, you would have an array of function buttons doing basic i. Once the GUI is lain out, you can then add the 'controller' references that link each button function to its Java implementation, e. This video is a bit old but still shows how easy Scene Builder is to use.

You can get the user input using Scanner. You can use the proper input validation using proper methods for different data types like next for String or nextInt for Integer. The most simple way to get user input would be to use Scanner. Here's an example of how it's supposed to be used:.

The line of code import java. Scanner; tells the program that the programmer will be using user inputs in their code. Like it says, it imports the scanner utility. This gives the variables the value of the user inputs.

Then you can use it in your code. Hope this helps. Stack Overflow for Teams — Collaborate and share knowledge with a private group.

Create a free Team What is Teams? Collectives on Stack Overflow. In this tutorial, you will learn simple ways to display output to users and take input from users in Java. Don't worry if you don't understand it. We will discuss class , public , and static in later chapters.

In the above example, we have shown the working of the print and println methods. To learn about the printf method, visit Java printf. Here, you can see that we have not used the quotation marks.

It is because to display integers, variables and so on, we don't use quotation marks. Here, first the value of variable number is evaluated. Java provides different ways to get input from the user. However, in this tutorial, you will learn to get input from user using the object of Scanner class. In order to use the object of Scanner , we need to import java. Scanner package. To learn more about importing packages in Java, visit Java Import Packages. Then, we need to create an object of the Scanner class.