Question

我使用Apache Commons'FileUtils.deleteDirectory()以递归方式删除文件夹，我注意到它遵循符号链接。

是否有替代品不会遵循符号链接，但只删除真实文件和文件夹？或者，我可以调整FileUtils来执行此操作吗？

Answer 1

我缩短了ripper234的答案。

/**
 * Recursively deletes `item`, which may be a directory.
 * Symbolic links will be deleted instead of their referents.
 * Returns a boolean indicating whether `item` still exists.
 * http://stackoverflow.com/questions/8666420
 */
public static boolean deleteRecursiveIfExists(File item) {
    if (!item.exists()) return true;
    if (!Files.isSymbolicLink(item.toPath()) && item.isDirectory()) {
        File[] subitems = item.listFiles();
        for (File subitem : subitems)
            if (!deleteRecursiveIfExists(subitem)) return false;
    }
    return item.delete();
}

Answer 2

整个问题似乎源于FileUtils.isSymlink()中的明显错误（我刚刚报告过）。我复制粘贴deleteDirectory()的代码，并使用Java 7的API代替检查符号链接，它可以工作：

public static void deleteDirectory(File directory) throws IOException {
    // See http://stackoverflow.com/questions/8666420/how-to-recursively-delete-a-folder-without-following-symlinks
    // Copied from http://grepcode.com/file/repo1.maven.org/maven2/commons-io/commons-io/2.1/org/apache/commons/io/FileUtils.java#FileUtils.deleteDirectory%28java.io.File%29
    if (!directory.exists()) {
        return;
    }

    if (!Files.isSymbolicLink(directory.toPath())) {
        cleanDirectory(directory);
    }

    if (!directory.delete()) {
        String message = "Unable to delete directory " + directory + ".";
        throw new IOException(message);
    }
}

private static void cleanDirectory(File directory) throws IOException {
    // Copied from http://grepcode.com/file/repo1.maven.org/maven2/commons-io/commons-io/2.1/org/apache/commons/io/FileUtils.java#FileUtils.cleanDirectory%28java.io.File%29
    if (!directory.exists()) {
        String message = directory + " does not exist";
        throw new IllegalArgumentException(message);
    }

    if (!directory.isDirectory()) {
        String message = directory + " is not a directory";
        throw new IllegalArgumentException(message);
    }

    File[] files = directory.listFiles();
    if (files == null) {  // null if security restricted
        throw new IOException("Failed to list contents of " + directory);
    }

    IOException exception = null;
    for (File file : files) {
        try {
            forceDelete(file);
        } catch (IOException ioe) {
            exception = ioe;
        }
    }

    if (exception != null) {
        throw exception;
    }
}

private static void forceDelete(File file) throws IOException {
    if (file.isDirectory()) {
        deleteDirectory(file);
    } else {
        boolean filePresent = file.exists();
        if (!file.delete()) {
            if (!filePresent) {
                throw new FileNotFoundException("File does not exist: " + file);
            }
            String message =
                    "Unable to delete file: " + file;
            throw new IOException(message);
        }
    }
}

如何在不遵循符号链接的情况下递归删除文件夹？

2 个答案: