08 2021 档案
摘要：System.console().readPassword()在idea中运行出现空指针异常 Console cons = System.console(); char[] chars = cons.readPassword(); String s=new String(chars); System
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摘要：Scanner scanner=new Scanner(System.in); File file=new File("C:\\Users\\Administrator\\Desktop","t1.txt"); String n=null; char[] b=new char[3]; try { F
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摘要：import java.io.*; public class E3 { public static void main(String[] args) { File file = new File("C:\\Users\\Administrator\\Desktop", "e3.txt"); byte
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摘要：File file=new File("C:\\Users\\Administrator\\Desktop","e1.txt"); System.out.println(file.exists()); 这段代码输出的是false File 类是对文件系统的映射 并不是硬盘上真实的文件，所以 new
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