MorePaths (Buck)

java.lang.Object
- com.facebook.buck.io.file.MorePaths

```
public class MorePaths
extends Object
```
Common functions that are done with a Path. If a function is going to take a ProjectFilesystem, then it should be in MoreProjectFilesystems instead.

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static com.google.common.io.ByteSource`	`asByteSource(Path path)`
`static int`	`commonSuffixLength(Path a, Path b)`
`static void`	`createSymLink(WindowsFS winFS, Path symLink, Path target)` Creates a symlink.
`static Path`	`dropInternalCaches(Path p)` Drop the cache in Path object.
`static Path`	`emptyOf(Path path)` Return empty path with the same filesystem as provided path
`static Path`	`expandHomeDir(Path path)` Expands "~/foo" into "/home/zuck/foo".
`static com.google.common.collect.ImmutableSet<Path>`	`filterForSubpaths(Iterable<Path> paths, Path root)` Filters out `Path` objects from `paths` that aren't a subpath of `root` and returns a set of paths relative to `root`.
`static Path`	`fixPath(Path p)` Drop any "." parts (useless).
`static String`	`getFileExtension(Path path)`
`static String`	`getNameWithoutExtension(Path file)`
`static Path`	`getParentOrEmpty(Path path)`
`static RelPath`	`getParentOrEmpty(RelPath path)`
`static Path`	`getRelativePath(Path path, Path baseDir)` Get the path of a file relative to a base directory.
`static String`	`getWindowsLongPathString(Path path)` Converts a path to an absolute Windows 'long path' as a string.
`static boolean`	`isDirectory(Path path, LinkOption... linkOptions)` Returns whether a path is a directory..
`static boolean`	`isEmpty(Path path)` Return true if provided path is empty path ("")
`static AbsPath`	`normalize(AbsPath path)` Type-safer version of `normalize(Path)`.
`static Path`	`normalize(Path path)` Get a path without unnecessary path parts.
`static String`	`pathWithPlatformSeparators(Path path)`
`static String`	`pathWithPlatformSeparators(String path)`
`static Path`	`relativize(Path path1, Path path2)` Get a relative path from path1 to path2, first normalizing each path.
`static RelPath`	`relativize(PathWrapper path1, PathWrapper path2)`
`static Path`	`relativizeWithDotDotSupport(Path basePath, Path childPath)` Returns a child path relative to a base path.
`static Optional<Pair<Path,com.google.common.collect.ImmutableList<Path>>>`	`splitOnCommonPrefix(Iterable<Path> paths)`
`static Pair<Path,Path>`	`stripCommonSuffix(Path a, Path b)`
`static String`	`stripPathPrefixAndExtension(Path fileName, String prefix)`
`static Optional<Path>`	`stripPrefix(Path p, Path prefix)`
`static java.util.function.Function<String,Path>`	`toPathFn(FileSystem fileSystem)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - pathWithPlatformSeparators
```
public static String pathWithPlatformSeparators(String path)
```
  - pathWithPlatformSeparators
```
public static String pathWithPlatformSeparators(Path path)
```
  - getParentOrEmpty
```
public static Path getParentOrEmpty(Path path)
```
  - getParentOrEmpty
```
public static RelPath getParentOrEmpty(RelPath path)
```
  - getRelativePath
```
public static Path getRelativePath(Path path,
                                   @Nullable
                                   Path baseDir)
```
    Get the path of a file relative to a base directory.
    
    Parameters:
    
    path - must reference a file, not a directory.
    
    baseDir - must reference a directory that is relative to a common directory with the path. may be null if referencing the same directory as the path.
    
    Returns:
    
    the relative path of path from the directory baseDir.
  - relativize
```
public static Path relativize(Path path1,
                              Path path2)
```
    Get a relative path from path1 to path2, first normalizing each path.
    This method is a workaround for JDK-6925169 (Path.relativize returns incorrect result if path contains "." or "..").
  - relativize
```
public static RelPath relativize(PathWrapper path1,
                                 PathWrapper path2)
```
  - relativizeWithDotDotSupport
```
public static Path relativizeWithDotDotSupport(Path basePath,
                                               Path childPath)
```
    Returns a child path relative to a base path. This is similar to `Path.relativize`, but supports base paths that start with "..", even in Java 11. JCL implementations of `Path.relativize` support base paths like this in Java 8, but not in Java 11.
    
    Parameters:
    
    basePath - the path against which childPath will be relativized
    
    childPath - the path to relativize against basePath
    
    Returns:
    
    childPath relativized against basePath
  - normalize
```
public static Path normalize(Path path)
```
    Get a path without unnecessary path parts.
    This method is a workaround for JDK-8037945 (Paths.get("").normalize() throws ArrayIndexOutOfBoundsException).
  - normalize
```
public static AbsPath normalize(AbsPath path)
```
    Type-safer version of normalize(Path).
  - emptyOf
```
public static Path emptyOf(Path path)
```
    Return empty path with the same filesystem as provided path
  - isEmpty
```
public static boolean isEmpty(Path path)
```
    Return true if provided path is empty path ("")
  - filterForSubpaths
```
public static com.google.common.collect.ImmutableSet<Path> filterForSubpaths(Iterable<Path> paths,
                                                                             Path root)
```
    Filters out Path objects from paths that aren't a subpath of root and returns a set of paths relative to root.
  - expandHomeDir
```
public static Path expandHomeDir(Path path)
```
    Expands "~/foo" into "/home/zuck/foo". Returns regular paths unmodified.
  - asByteSource
```
public static com.google.common.io.ByteSource asByteSource(Path path)
```
  - getFileExtension
```
public static String getFileExtension(Path path)
```
  - getNameWithoutExtension
```
public static String getNameWithoutExtension(Path file)
```
  - stripPathPrefixAndExtension
```
public static String stripPathPrefixAndExtension(Path fileName,
                                                 String prefix)
```
  - stripPrefix
```
public static Optional<Path> stripPrefix(Path p,
                                         Path prefix)
```
  - toPathFn
```
public static java.util.function.Function<String,Path> toPathFn(FileSystem fileSystem)
```
  - fixPath
```
public static Path fixPath(Path p)
```
    Drop any "." parts (useless). Do keep ".." parts; don't normalize them away.
    Note that while Path objects provide a Path.normalize() method for eliminating redundant parts of paths like in foo/a/../b/c, changing its internal parts (and actually using the filesystem), we don't use those methods to clean up the incoming paths; we only strip empty parts, and those consisting only of . because doing so maps exactly-same paths together, and can't influence where it may point to, whereas .. and symbolic links might.
  - dropInternalCaches
```
public static Path dropInternalCaches(Path p)
```
    Drop the cache in Path object.
    Path's implementation class UnixPath, will lazily initialize a String representation and store it in the object when #toString() is called for the first time. This doubles the memory requirement for the Path object.
    This hack constructs a new path, dropping the cached toString value.
    Due to the nature of what this function does, it's very sensitive to the implementation. Any calls to #toString() on the returned object would also recreate the cached string value.
  - commonSuffixLength
```
public static int commonSuffixLength(Path a,
                                     Path b)
```
  - stripCommonSuffix
```
public static Pair<Path,Path> stripCommonSuffix(Path a,
                                                Path b)
```
  - splitOnCommonPrefix
```
public static Optional<Pair<Path,com.google.common.collect.ImmutableList<Path>>> splitOnCommonPrefix(Iterable<Path> paths)
```
  - createSymLink
```
public static void createSymLink(@Nullable
                                 WindowsFS winFS,
                                 Path symLink,
                                 Path target)
                          throws IOException
```
    Creates a symlink.
    
    Parameters:
    
    winFS - WindowsFS object that creates symlink on Windows using different permission level implementations.
    
    symLink - the symlink to create.
    
    target - the target of the symlink.
    
    Throws:
    
    IOException
  - isDirectory
```
public static boolean isDirectory(Path path,
                                  LinkOption... linkOptions)
```
    Returns whether a path is a directory..
    
    Parameters:
    
    path - An absolute file name
    
    linkOptions - Link options
    
    Returns:
    
    Whether the path is a directory.
  - getWindowsLongPathString
```
public static String getWindowsLongPathString(Path path)
```
    Converts a path to an absolute Windows 'long path' as a string. https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file#maximum-path-length-limitation
    
    Parameters:
    
    path - The path to transform to a long path appropriate string form
    
    Returns:
    
    The string representation of the path appropriate for long file name usage.

Class MorePaths

Method Summary

Methods inherited from class java.lang.Object

Method Detail

pathWithPlatformSeparators

pathWithPlatformSeparators

getParentOrEmpty

getParentOrEmpty

getRelativePath

relativize

relativize

relativizeWithDotDotSupport

normalize

normalize

emptyOf

isEmpty

filterForSubpaths

expandHomeDir

asByteSource

getFileExtension

getNameWithoutExtension

stripPathPrefixAndExtension

stripPrefix

toPathFn

fixPath

dropInternalCaches

commonSuffixLength

stripCommonSuffix

splitOnCommonPrefix

createSymLink

isDirectory

getWindowsLongPathString