Links, Symbolic or Otherwise链接，符号或其他

As mentioned previously, the java.nio.file package, and the Path class in particular, is "link aware." 如前所述，java.nio.file包，特别是Path类，是“链接感知”的。Every Path method either detects what to do when a symbolic link is encountered, or it provides an option enabling you to configure the behavior when a symbolic link is encountered.每个Path方法要么检测遇到符号链接时要执行的操作，要么提供一个选项，使您能够配置遇到符号链接时的行为。

The discussion so far has been about symbolic or soft links, but some file systems also support hard links. 到目前为止的讨论都是关于符号链接或软链接的，但是一些文件系统也支持硬链接。Hard links are more restrictive than symbolic links, as follows:硬链接比符号链接更具限制性，如下所示：

• The target of the link must exist.链接的目标必须存在。
• Hard links are generally not allowed on directories.目录上通常不允许硬链接。
• Hard links are not allowed to cross partitions or volumes. 硬链接不允许跨分区或卷。Therefore, they cannot exist across file systems.因此，它们不能跨文件系统存在。
• A hard link looks, and behaves, like a regular file, so they can be hard to find.硬链接的外观和行为与常规文件类似，因此很难找到它们。
• A hard link is, for all intents and purposes, the same entity as the original file. 无论出于何种目的，硬链接都是与原始文件相同的实体。They have the same file permissions, time stamps, and so on. 它们具有相同的文件权限、时间戳等。All attributes are identical.所有属性都是相同的。

Because of these restrictions, hard links are not used as often as symbolic links, but the Path methods work seamlessly with hard links.由于这些限制，硬链接不像符号链接那样经常使用，但是Path方法可以无缝地与硬链接配合使用。

Several methods deal specifically with links and are covered in the following sections:有几种方法专门处理链接，并在以下章节中介绍：

• Creating a Symbolic Link创建符号链接
• Creating a Hard Link创建硬链接
• Detecting a Symbolic Link检测符号链接
• Finding the Target of a Link查找链接的目标

Creating a Symbolic Link创建符号链接

If your file system supports it, you can create a symbolic link by using the createSymbolicLink(Path, Path, FileAttribute<?>) method. 如果您的文件系统支持，则可以使用createSymbolicLink(Path, Path, FileAttribute<?>)方法创建符号链接。The second Path argument represents the target file or directory and might or might not exist. 第二个Path参数表示目标文件或目录，可能存在，也可能不存在。The following code snippet creates a symbolic link with default permissions:以下代码段使用默认权限创建符号链接：

Path newLink = ...;
Path target = ...;
try {
    Files.createSymbolicLink(newLink, target);
} catch (IOException x) {
    System.err.println(x);
} catch (UnsupportedOperationException x) {
    // Some file systems do not support symbolic links.
    System.err.println(x);
}

The FileAttributes vararg enables you to specify initial file attributes that are set atomically when the link is created. FileAttributesvararg允许您指定在创建链接时以原子方式设置的初始文件属性。However, this argument is intended for future use and is not currently implemented.然而，这一论点是为了将来使用，目前尚未实施。

Creating a Hard Link创建硬链接

You can create a hard (or regular) link to an existing file by using the createLink(Path, Path) method. 可以使用createLink(Path, Path)方法创建指向现有文件的硬链接（或常规链接）。The second Path argument locates the existing file, and it must exist or a NoSuchFileException is thrown. 第二个Path参数定位现有文件，该文件必须存在，否则将引发NoSuchFileException。The following code snippet shows how to create a link:以下代码段显示了如何创建链接：

Path newLink = ...;
Path existingFile = ...;
try {
    Files.createLink(newLink, existingFile);
} catch (IOException x) {
    System.err.println(x);
} catch (UnsupportedOperationException x) {
    // Some file systems do not
    // support adding an existing
    // file to a directory.
    System.err.println(x);
}

Detecting a Symbolic Link检测符号链接

To determine whether a Path instance is a symbolic link, you can use the isSymbolicLink(Path) method. 要确定Path实例是否为符号链接，可以使用isSymbolicLink(Path)方法。The following code snippet shows how:以下代码段显示了如何：

Path file = ...;
boolean isSymbolicLink =
    Files.isSymbolicLink(file);

For more information, see Managing Metadata.有关更多信息，请参阅管理元数据。

Finding the Target of a Link查找链接的目标

You can obtain the target of a symbolic link by using the readSymbolicLink(Path) method, as follows:您可以使用readSymbolicLink(Path)方法获得符号链接的目标，如下所示：

Path link = ...;
try {
    System.out.format("Target of link" +
        " '%s' is '%s'%n", link,
        Files.readSymbolicLink(link));
} catch (IOException x) {
    System.err.println(x);
}

If the Path is not a symbolic link, this method throws a NotLinkException.如果Path不是符号链接，此方法将抛出NotLinkException。