java - java中如何写入文件？

Question

我面临文件写入问题，实际上当我运行下面的代码时，while 循环会无限次迭代。

package com.demo.io;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

public class CopyFile {

    public static void main(String[] args) {

        FileInputStream in = null;
        FileOutputStream out = null;
        try {
            in = new FileInputStream("C:/Users/s.swain/Desktop/loginissue.txt");
            out = new FileOutputStream("C:/Users/s.swain/Desktop/output.txt");
            int c = in.read();
            while (c != -1) {
                System.out.println(c);
                out.write(c);
            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (in != null) {
                try {
                    in.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            if (out != null) {
                try {
                    out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

任何人都可以告诉我如何编写这个文件。

谢谢

西坦苏

Answer 1

这个条件永远保持true为真，因为你永远不会在while-loop中更新c:

while (c != -1) {

使用in.read 内部 while-loop!

int c = in.read();
while (c != -1) {
    System.out.println(c);
    out.write(c);
    c = in.read();
}