请考虑以下示例 Java 类(下面的 pom.xml):

package test.filedelete;

import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.file.Files;
import java.nio.file.NoSuchFileException;
import java.nio.file.Path;

import org.apache.commons.io.IOUtils;

public class Main
{
    public static void main(String[] args) throws IOException
    {
        byte[] bytes = "testtesttesttesttesttesttesttesttesttest".getBytes();
        InputStream is = new ByteArrayInputStream(bytes);

        Path tempFileToBeDeleted = Files.createTempFile("test", "");
        OutputStream os = Files.newOutputStream(tempFileToBeDeleted);
        IOUtils.copy(is, os);

        deleteAndCheck(tempFileToBeDeleted);

        // breakpoint 1
        System.out.println("\nClosing stream\n");

        os.close();

        deleteAndCheck(tempFileToBeDeleted);
    }

    private static void deleteAndCheck(Path file) throws IOException
    {
        System.out.println("Deleting file: " + file);
        try
        {
            Files.delete(file);
        }
        catch (NoSuchFileException e)
        {
            System.out.println("No such file");
        }
        System.out.println("File really deleted: " + !Files.exists(file));

        System.out.println("Recreating deleted file ...");
        try
        {
            Files.createFile(file);
            System.out.println("Recreation successful");
        }
        catch (IOException e)
        {
            System.out.println("Recreation not possible, exception: " + e.getClass().getName());
        }
    }
}

Deleting file: C:\Users\MSCHAE~1\AppData\Local\Temp\test6100073603559201768
File really deleted: true
Recreating deleted file ...
Recreation not possible, exception: java.nio.file.AccessDeniedException

Closing stream

Deleting file: C:\Users\MSCHAE~1\AppData\Local\Temp\test6100073603559201768
No such file
File really deleted: true
Recreating deleted file ...
Recreation successful

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>test</groupId>
    <artifactId>filedelete</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>commons-io</groupId>
            <artifactId>commons-io</artifactId>
            <version>2.4</version>
        </dependency>
    </dependencies>
</project>

最佳答案

你能删除一个打开的文件吗？

打开文件时删除文件的目录项是完全有效的。在 Unix 中，这是默认语义，只要 FILE_SHARE_DELETE ，Windows 的行为就类似。在对该文件打开的所有文件句柄上设置。

[编辑:感谢@couling 的讨论和更正]

但是，有一点不同:Unix 立即删除文件名 , 而 Windows 仅在最后一个句柄关闭时删除文件名 .但是，它会阻止您打开同名文件，直到(已删除)文件的最后一个句柄关闭。

去搞清楚 ...

然而，在这两个系统上，删除文件并不一定会使文件消失，只要仍有打开的句柄，它仍然会占用磁盘空间。文件占用的空间只有在最后一个打开的句柄关闭时才会释放。

游览:Windows

必须在 Windows 上指定标志使大多数人认为 Windows 无法删除打开的文件，但实际上并非如此。这只是默认行为。

CreateFile() :

Enables subsequent open operations on a file or device to request delete access.

Otherwise, other processes cannot open the file or device if they request delete access.

If this flag is not specified, but the file or device has been opened for delete access, the function fails. Note Delete access allows both delete and rename operations.

The DeleteFile function marks a file for deletion on close. Therefore, the file deletion does not occur until the last handle to the file is closed. Subsequent calls to CreateFile to open the file fail with ERROR_ACCESS_DENIED.

关于java - 使用 Files.delete() 删除文件时的奇怪行为，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/31606978/