我得到不同的结果为Files.exists(path),以path.toFile().exists()在Windows本地文件.我可以在Windows资源管理器中看到这个文件,虽然我有(随机)修改过的权限,也许权限没有意义.
但是,这并不能解释为什么旧方法返回true并且新方法返回false.该文件确定存在但可能对运行Java代码的用户不可见,因此我不确定应该是什么样的正确答案.我也无法看到如何查看哪个用户正在运行代码,计算机上只有一个真正的用户Paul,但我想知道是否以管理员身份运行或不影响事情.
System.out.println("Path Exists(1):"+Files.exists(path));
System.out.println("Path Exist(2) :"+path.toFile().exists());
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给
Path Exists(1):false
Path Exist(2) :true
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也
System.out.println("Path readable(3) :"+Files.isReadable(path));
System.out.println("Path readable(4):"+path.toFile().canRead());
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以同样的方式给予
Path readable(3) :false
Path readable(4):true
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权限输出
File C:\Code\jthink\opensrc\jaudiotagger\testdata\test157.dsf permissions
owner:PCLAPTOP\Paul
NT AUTHORITY\SYSTEM:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:DENY
BUILTIN\Administrators:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:DENY
BUILTIN\Administrators:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:ALLOW
NT AUTHORITY\SYSTEM:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/DELETE_CHILD/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/WRITE_ACL/WRITE_OWNER/SYNCHRONIZE:ALLOW
BUILTIN\Users:READ_DATA/READ_NAMED_ATTRS/EXECUTE/READ_ATTRIBUTES/READ_ACL/SYNCHRONIZE:ALLOW
NT AUTHORITY\Authenticated Users:READ_DATA/WRITE_DATA/APPEND_DATA/READ_NAMED_ATTRS/WRITE_NAMED_ATTRS/EXECUTE/READ_ATTRIBUTES/WRITE_ATTRIBUTES/DELETE/READ_ACL/SYNCHRONIZE:ALLOW
c:\Code\jthink\opensrc\jaudiotagger>attrib C:\Code\jthink\opensrc\jaudiotagger\testdata\test157.dsf
A R C:\Code\jthink\opensrc\jaudiotagger\testdata\test157.dsf
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更新 我没有得出结论,但认为这些信息可能有用.
我在IntelliJ IDE中运行代码而没有启用IDE Run选项的IDE Run程序,启用此功能后,Java应用程序也获得了管理员权限.
感兴趣的是另一个文件我没有添加任何DENY权限,我只是禁用了继承权限并从所有组中删除了READ权限.然后,当我作为用户运行而没有运行管理员启用它无法读取文件,此代码也无法输出任何信息
AclFileAttributeView view = Files.getFileAttributeView(path, AclFileAttributeView.class);
if (view != null)
{
sb.append("Owner:"+view.getOwner().getName()+"**");
for (AclEntry acl : view.getAcl())
{
sb.append(acl.principal()+"**");
for(AclEntryPermission aep:acl.permissions()) …Run Code Online (Sandbox Code Playgroud) 为什么此代码返回false?
Path path = Paths.get("C:\\aaa\\bbb\\ccc");
Files.exists(path); // false!?
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即使当我从文件(存在)转换为它时:
File file = new File("C:\\aaa\\bbb\\ccc");
file.exists(); // true!!!
Path path = file.toPath();
Files.exists(path); // still false!?
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