org.apache.hadoop.fs

Class Path

java.lang.Object

org.apache.hadoop.fs.Path

All Implemented Interfaces:

ObjectInputValidation, Serializable, Comparable<Path>

@Stringable
 @InterfaceAudience.Public
 @InterfaceStability.Stable
public class Path
extends Object
implements Comparable<Path>, Serializable, ObjectInputValidation

Names a file or directory in a FileSystem. Path strings use slash as the directory separator.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static String	CUR_DIR The current directory, ".".
static String	SEPARATOR The directory separator, a slash.
static char	SEPARATOR_CHAR The directory separator, a slash, as a character.
static boolean	WINDOWS Whether the current host is a Windows machine.

Constructor Summary

Constructors

Constructor and Description
Path(Path parent, Path child) Create a new Path based on the child path resolved against the parent path.
Path(Path parent, String child) Create a new Path based on the child path resolved against the parent path.
Path(String pathString) Construct a path from a String.
Path(String parent, Path child) Create a new Path based on the child path resolved against the parent path.
Path(String parent, String child) Create a new Path based on the child path resolved against the parent path.
Path(String scheme, String authority, String path) Construct a Path from components.
Path(URI aUri) Construct a path from a URI

Method Summary

Modifier and Type	Method and Description
int	compareTo(Path o)
int	depth() Returns the number of elements in this path.
boolean	equals(Object o)
FileSystem	getFileSystem(Configuration conf) Return the FileSystem that owns this Path.
String	getName() Returns the final component of this path.
Optional<Path>	getOptionalParentPath() Returns the parent of a path as Optional or Optional.empty() i.e an empty Optional if at root.
Path	getParent() Returns the parent of a path or null if at root.
static Path	getPathWithoutSchemeAndAuthority(Path path) Return a version of the given Path without the scheme information.
int	hashCode()
boolean	isAbsolute() Returns true if the path component (i.e.
boolean	isAbsoluteAndSchemeAuthorityNull() Returns true if the path component (i.e.
boolean	isRoot() Returns true if and only if this path represents the root of a file system.
boolean	isUriPathAbsolute() Returns true if the path component (i.e.
static boolean	isWindowsAbsolutePath(String pathString, boolean slashed) Determine whether a given path string represents an absolute path on Windows.
Path	makeQualified(FileSystem fs) Deprecated. use makeQualified(URI, Path)
static Path	mergePaths(Path path1, Path path2) Merge 2 paths such that the second path is appended relative to the first.
Path	suffix(String suffix) Adds a suffix to the final name in the path.
String	toString()
URI	toUri() Convert this Path to a URI.
void	validateObject() Validate the contents of a deserialized Path, so as to defend against malicious object streams.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

SEPARATOR

public static final String SEPARATOR

The directory separator, a slash.

See Also:

Constant Field Values

SEPARATOR_CHAR

public static final char SEPARATOR_CHAR

The directory separator, a slash, as a character.

See Also:

Constant Field Values

CUR_DIR

public static final String CUR_DIR

The current directory, ".".

See Also:

Constant Field Values

WINDOWS

public static final boolean WINDOWS

Whether the current host is a Windows machine.

Constructor Detail

Path

public Path(String parent,
            String child)

Create a new Path based on the child path resolved against the parent path.

Parameters:

parent - the parent path

child - the child path

Path

public Path(Path parent,
            String child)

Create a new Path based on the child path resolved against the parent path.

Parameters:

parent - the parent path

child - the child path

Path

public Path(String parent,
            Path child)

Create a new Path based on the child path resolved against the parent path.

Parameters:

parent - the parent path

child - the child path

Path

public Path(Path parent,
            Path child)

Create a new Path based on the child path resolved against the parent path.

Parameters:

parent - the parent path

child - the child path

Path

public Path(String pathString)
     throws IllegalArgumentException

Construct a path from a String. Path strings are URIs, but with unescaped elements and some additional normalization.

Parameters:

pathString - the path string

Throws:

IllegalArgumentException

Path

public Path(URI aUri)

Construct a path from a URI

Parameters:

aUri - the source URI

Path

public Path(String scheme,
            String authority,
            String path)

Construct a Path from components.

Parameters:

scheme - the scheme

authority - the authority

path - the path

Method Detail

getPathWithoutSchemeAndAuthority

public static Path getPathWithoutSchemeAndAuthority(Path path)

Return a version of the given Path without the scheme information.

Parameters:

path - the source Path

Returns:

a copy of this Path without the scheme information

mergePaths

public static Path mergePaths(Path path1,
                              Path path2)

Merge 2 paths such that the second path is appended relative to the first. The returned path has the scheme and authority of the first path. On Windows, the drive specification in the second path is discarded.

Parameters:

path1 - the first path

path2 - the second path, to be appended relative to path1

Returns:

the merged path

isWindowsAbsolutePath

public static boolean isWindowsAbsolutePath(String pathString,
                                            boolean slashed)

Determine whether a given path string represents an absolute path on Windows. e.g. "C:/a/b" is an absolute path. "C:a/b" is not.

Parameters:

pathString - the path string to evaluate

slashed - true if the given path is prefixed with "/"

Returns:

true if the supplied path looks like an absolute path with a Windows drive-specifier

toUri

public URI toUri()

Convert this Path to a URI.

Returns:

this Path as a URI

getFileSystem

public FileSystem getFileSystem(Configuration conf)
                         throws IOException

Return the FileSystem that owns this Path.

Parameters:

conf - the configuration to use when resolving the FileSystem

Returns:

the FileSystem that owns this Path

Throws:

IOException - thrown if there's an issue resolving the FileSystem

isAbsoluteAndSchemeAuthorityNull

public boolean isAbsoluteAndSchemeAuthorityNull()

Returns true if the path component (i.e. directory) of this URI is absolute and the scheme is null, and the authority is null.

Returns:

whether the path is absolute and the URI has no scheme nor authority parts

isUriPathAbsolute

public boolean isUriPathAbsolute()

Returns true if the path component (i.e. directory) of this URI is absolute.

Returns:

whether this URI's path is absolute

isAbsolute

public boolean isAbsolute()

Returns true if the path component (i.e. directory) of this URI is absolute. This method is a wrapper for isUriPathAbsolute().

Returns:

whether this URI's path is absolute

isRoot

public boolean isRoot()

Returns true if and only if this path represents the root of a file system.

Returns:

true if and only if this path represents the root of a file system

getName

public String getName()

Returns the final component of this path.

Returns:

the final component of this path

getParent

public Path getParent()

Returns the parent of a path or null if at root. Better alternative is getOptionalParentPath() to handle nullable value for root path.

Returns:

the parent of a path or null if at root

getOptionalParentPath

public Optional<Path> getOptionalParentPath()

Returns the parent of a path as Optional or Optional.empty() i.e an empty Optional if at root.

Returns:

Parent of path wrappen in Optional. Optional.empty() i.e an empty Optional if at root.

suffix

public Path suffix(String suffix)

Adds a suffix to the final name in the path.

Parameters:

suffix - the suffix to add

Returns:

a new path with the suffix added

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

compareTo

public int compareTo(Path o)

Specified by:

compareTo in interface Comparable<Path>

depth

public int depth()

Returns the number of elements in this path.

Returns:

the number of elements in this path

makeQualified

@Deprecated
public Path makeQualified(FileSystem fs)

Deprecated. use makeQualified(URI, Path)

Returns a qualified path object for the FileSystem's working directory.

Parameters:

fs - the target FileSystem

Returns:

a qualified path object for the FileSystem's working directory

validateObject

public void validateObject()
                    throws InvalidObjectException

Validate the contents of a deserialized Path, so as to defend against malicious object streams.

Specified by:

validateObject in interface ObjectInputValidation

Throws:

InvalidObjectException - if there's no URI