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对我之前的问题的跟进 - Java：如何读取目录文件夹，计算和显示文件数量并复制到另一个文件夹？，我要读取一个文件夹，统计文件夹中的文件（任何文件类型），显示文件数量，然后将其复制到新文件夹。但是，我收到以下异常：

线程“主”java.io.FileNotFoundException 中的异常：C:\project\curFolder（访问被拒绝）C:\project\newFolder 已经存在：继续处理！在 java.io.FileInputStream.open(Native Method) 在 java.io.FileInputStream.(FileInputStream.java:120) 在 filetransfer.FileTransfer.copyFiles(FileTransfer.java:54) 在 filetransfer.FileTransfer.checkDir(FileTransfer.java: 44) 在 filetransfer.FileTransfer.readDirectory(FileTransfer.java:29) 在 filetransfer.FileTransfer.main(FileTransfer.java:12) Java 结果：1 BUILD SUCCESSFUL（总时间：0 秒）

请记住我是学生。这是我到目前为止所做的：

public class FileTransfer {

    public static void main(String[] args) throws FileNotFoundException, IOException {
         readDirectory();
    }

public static void readDirectory() throws FileNotFoundException, IOException {
        //create new file object with location of folder
        File curFolder = new File("C:/project/curFolder/");
        int totalFiles = 0;
        //for loop to count the files in the directory using listfiles method
        for (File file : curFolder.listFiles()) {
            //determine if the file object is a file
            if (file.isFile()) {
                //count files ++
                totalFiles++;
            }
        }
        //display number of files in directory
        System.out.println("Number of files: " + totalFiles);
        checkDir();
    }

    public static void checkDir() throws FileNotFoundException, IOException {
        //check if destination directory exist, if not create directory
        //create new file object with copy folder destination
        File newFolder = new File("C:/project/newFolder/");
        //Check if folder exist: True: Println with message(true and continuing)
        if (newFolder.exists()) {
            System.out.println(newFolder + " already exist: Continuing with process!");
        } else {
            //False: Create Dir
            newFolder.mkdir();
            System.out.println(newFolder + " created!");
        }
        copyFiles();
    }

    public static void copyFiles() throws FileNotFoundException, IOException {
        //copy files from specified directory to new directory
        File fromCur = new File("C:/project/curFolder/");
        File toNew = new File("C:/project/newFolder/");
        FileInputStream from = null;
        FileOutputStream to = null;
        try {
            from = new FileInputStream(fromCur);
            to = new FileOutputStream(toNew);
            byte[] buffer = new byte[4096];
            int bytesRead;

            while ((bytesRead = from.read(buffer)) != -1) {
                to.write(buffer, 0, bytesRead);
            }
        } finally {
            if (from != null) {
                try {
                    from.close();
                } catch (IOException e) {
                    System.out.println(e.getMessage());
                }
            }
            if (to != null) {
                try {
                    to.close();
                } catch (IOException e) {
                    System.out.println(e.getMessage());
                }
            }
        }
    }
}
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2 回答 2

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您要做的是复制文件夹本身，而不是其中的文件。尝试更改copyFiles方法的这一部分：

    File fromCur = new File("C:/project/curFolder/");
        File toNew = new File("C:/project/newFolder/");
        FileInputStream from = null;
        FileOutputStream to = null;

    try {

    to = new FileOutputStream(toNew);
    byte[] buffer = new byte[4096];
    int bytesRead;

    for (File fileTemp : fromCur.listFiles()) {
     if (fileTemp.isFile()) {
        from = new FileInputStream(fileTemp);
         while ((bytesRead = from.read(buffer)) != -1) {
          to.write(buffer, 0, bytesRead);
         }
     }
    }

循环时，这将引用您文件夹中的文件，而不是文件夹本身。

于 2012-10-24T10:18:56.453 回答
0

错误在于以下行：

from = new FileInputStream(fromCur);

因为C:\project\curFolder是文件夹而不是文件。根据FileInputStream文档，您看到的异常是正确的。

抛出： FileNotFoundException - 如果文件不存在，是目录而不是常规文件，或者由于某些其他原因无法打开读取。

（我在上面引用的重点）

我相信您可能会想要检查输入文件是否是一个目录，然后列出文件并逐个复制它们。

于 2012-10-24T10:19:06.060 回答