Java如何从控制台读取输入

在java中，可以使用从控制台或键盘读取输入：

• java.util.Scanner类
• java.io.BufferedReader类
• java.io.Console类

使用java.util.Scanner从控制台读取输入

以下是使用Scanner类从控制台读取输入的示例。

文件：ConsoleInputExample1.java –

package com.yiibai.tutorial.io;  import java.util.Scanner;  /**  * @author yiibai  */ public class ConsoleInputExample1 {     public static void main(String[] args) {         Scanner scanner = new Scanner(System.in);          // Read String         System.out.println("Enter your name.");         String name = scanner.nextLine();         System.out.println("Your name is : " + name);          // Read Int         System.out.println("Enter your age.");         int age = scanner.nextInt();         System.out.println("Your age is : " + age);          scanner.close();     } } 

执行上面示例代码，得到以下结果：

使用java.io.BufferedReader从控制台读取输入

以下示例使用BufferedReader类的readLine()方法从控制台读取输入字符串。

文件：ConsoleInputExample2.java –

package com.yiibai.tutorial.io;  import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader;  /**  * @author yiibai  */ public class ConsoleInputExample2 {     public static void main(String[] args) {         BufferedReader bufferedReader = null;         try {             bufferedReader = new BufferedReader(new InputStreamReader(System.in));              // Read first line             System.out.println("Enter first line");             String line = bufferedReader.readLine();             System.out.println("First line is : " + line);              // Read second line             System.out.println("/nEnter second line");             line = bufferedReader.readLine();             System.out.println("Second line is : " + line);          } catch (IOException e) {             e.printStackTrace();         } finally {             try {                 if (bufferedReader != null) {                     bufferedReader.close();                 }             } catch (IOException e) {                 e.printStackTrace();             }         }      } } 

执行上面示例代码，得到以下结果：

Enter first line This is an example of reading input First line is : This is an example of reading input  Enter second line from console using buffered reader. Second line is : from console using buffered reader. 

使用java.io.Console读取输入

以下示例不适用于IDE。可以从窗口命令提示符运行此示例。

package com.yiibai.tutorial.io;  import java.io.Console;  /**  * @author yiibai  */ public class ConsoleInputExample3 {     public static void main(String[] args) {         Console console = System.console();          if (console != null) {             // Read String             System.out.println("Enter username: ");             String name = console.readLine();             System.out.println("Username is : " + name);              // Read password             System.out.println("Enter your password.");             char[] password = console.readPassword();             System.out.println("Password is : " + new String(password));         }      } } 

执行上面示例代码，得到以下结果：

Enter username: yiibai Username is : yiibai Enter your password.  Password is : abcd@1234