屏蔽从控制台输入的密码:Java

Question

如何从控制台输入掩码密码？我正在使用Java 6.

我尝试过使用console.readPassword(),但它不起作用.一个完整的例子可能对我有帮助.

这是我的代码:

import java.io.BufferedReader;
import java.io.Console;
import java.io.IOException;
import java.io.InputStreamReader;

public class Test 
{   
    public static void main(String[] args) 
    {   
        Console console = System.console();

        console.printf("Please enter your username: ");
        String username = console.readLine();
        console.printf(username + "\n");

        console.printf("Please enter your password: ");
        char[] passwordChars = console.readPassword();
        String passwordString = new String(passwordChars);

        console.printf(passwordString + "\n");
    }
}

我得到一个NullPointerException ...

Answer 1

一个完整的例子？运行此代码:(注意:此示例最好在控制台中运行,而不是在IDE中运行,因为在这种情况下System.console()方法可能会返回null.)

import java.io.Console;
public class Main {

    public void passwordExample() {        
        Console console = System.console();
        if (console == null) {
            System.out.println("Couldn't get Console instance");
            System.exit(0);
        }

        console.printf("Testing password%n");
        char[] passwordArray = console.readPassword("Enter your secret password: ");
        console.printf("Password entered was: %s%n", new String(passwordArray));

    }

    public static void main(String[] args) {
        new Main().passwordExample();
    }
}

Answer 2

您将使用Console类

char[] password = console.readPassword("Enter password");  
Arrays.fill(password, ' ');

通过执行readPassword,可以禁用回显.验证密码后,最好覆盖数组中的任何值.

如果你从一个ide运行它会失败,请看这个解释得到一个彻底的答案:解释