java中的freopen

最新推荐文章于 2023-01-28 23:36:07 发布

转载最新推荐文章于 2023-01-28 23:36:07 发布 · 463 阅读

本文展示了一个使用Java进行文件输入输出操作的简单示例，包括打开输入输出流，读取整数并打印到另一个文件的过程。代码使用了FileInputStream和PrintStream进行基本的文件读写操作。

public class Main {
  static private final String INPUT = "C:/input.txt";
  static private final String OUTPUT = "C:/output.txt";

  public static void main(String args[]) {
      // open I/O files
      FileInputStream instream = null;
      PrintStream outstream = null;
   
      try {
          instream = new FileInputStream(INPUT);
          outstream = new PrintStream(new FileOutputStream(OUTPUT));
          System.setIn(instream);
          System.setOut(outstream);
      } catch (Exception e) {
          System.err.println("Error Occurred.");
      }
   
      Scanner in = new Scanner(System.in);
      for (;in.hasNext();) {
          int x = in.nextInt();
          System.out.println(x);
      }
   
      System.err.println("done.");
      return;
  }

}