During the development of Java programs, it is common to need to obtain input values ??from the keyboard. Java does not provide a function to obtain input, which does not mean that we are helpless when encountering this situation. Let's take a look at how to input in Java.
Several methods will be listed below:
Method 1: Receive a character from the console and print it out
import java.io.*;
public static void main(String [] args) throws IOException{
System.out.print("Enter a Char:");
char i = (char) System.in.read();
System.out.println("your char is :"+i);
}Although this method achieves obtaining the input characters from the keyboard, System.in.read() can only obtain one character . At the same time, the type of the incoming variable can only be char. When we When we input a number and hope to get an integer variable, we have to modify the variable type, which is more troublesome.
Method 2: Receive a string from the console and print it out. In this question, we need to use the BufferedReader class and the InputStreamReader class
import java.io.*;
public static void main(String [] args) throws IOException{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String str = null;
System.out.println("Enter your value:");
str = br.readLine();
System.out.println("your value is :"+str);
}so that we can get the string we input.
Method 3: I think this method is the simplest and most powerful, which is to use the Scanner class
java.util.Scanner is a new feature of Java5, we can use the Scanner class to Get user input.
import java.util.Scanner;
public static void main(String [] args) {
Scanner sc = new Scanner(System.in);
System.out.println("請輸入你的姓名：");
String name = sc.nextLine();
System.out.println("請輸入你的年齡：");
int age = sc.nextInt();
System.out.println("請輸入你的工資：");
float salary = sc.nextFloat();
System.out.println("你的信息如下：");
System.out.println("姓名："+name+"\n"+"年齡："+age+"\n"+"工資："+salary);
}This code has shown that the Scanner class, whether it is a string, integer data or float type variable, only needs to make a small change to achieve the function! Undoubtedly he is the most powerful!
For more java knowledge, please pay attention to java basic tutorial.
The above is the detailed content of How to input in java?. For more information, please follow other related articles on the PHP Chinese website!
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