Class FS

  • Direct Known Subclasses:
    FS_POSIX, FS_Win32

    public abstract class FS
    extends java.lang.Object
    Abstraction to support various file system operations not in Java.
    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  FS.Attributes
      File attributes we typically care for.
      static class  FS.FSFactory
      This class creates FS instances.
    • Field Summary

      Fields 
      Modifier and Type Field Description
      static FS DETECTED
      The auto-detected implementation selected for this operating system and JRE.
    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      protected FS()
      Constructs a file system abstraction.
      protected FS​(FS src)
      Initialize this FS using another's current settings.
    • Method Summary

      All Methods Static Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      abstract boolean canExecute​(java.io.File f)
      Determine if the file is executable (or not).
      void createSymLink​(java.io.File path, java.lang.String target)
      Create a symbolic link
      void delete​(java.io.File f)
      Delete a file.
      static FS detect()
      Auto-detect the appropriate file system abstraction.
      static FS detect​(java.lang.Boolean cygwinUsed)
      Auto-detect the appropriate file system abstraction, taking into account the presence of a Cygwin installation on the system.
      protected abstract java.io.File discoverGitPrefix()  
      boolean exists​(java.io.File path)
      Tests if the path exists, in case of a symbolic link, true even if the target does not exist
      java.io.File findHook​(Repository repository, Hook hook)
      Tries to find a hook matching the given one in the given repository.
      FS.Attributes getAttributes​(java.io.File path)  
      java.io.File gitPrefix()  
      protected ProcessResult internalRunIfPresent​(Repository repository, Hook hook, java.lang.String[] args, java.io.PrintStream outRedirect, java.io.PrintStream errRedirect, java.lang.String stdinArgs)
      abstract boolean isCaseSensitive()
      Is this file system case sensitive
      boolean isDirectory​(java.io.File path)
      Check if path is a directory.
      boolean isFile​(java.io.File path)
      Examine if path represents a regular file.
      boolean isHidden​(java.io.File path)  
      boolean isSymLink​(java.io.File path)  
      long lastModified​(java.io.File f)
      Get the last modified time of a file system object.
      long length​(java.io.File path)
      Get the length of a file or link, If the OS/JRE supports symbolic links it's the length of the link, else the length of the target.
      abstract FS newInstance()  
      java.io.File normalize​(java.io.File file)
      Normalize the unicode path to composed form.
      java.lang.String normalize​(java.lang.String name)
      Normalize the unicode path to composed form.
      protected static java.lang.String readPipe​(java.io.File dir, java.lang.String[] command, java.lang.String encoding)
      Execute a command and return a single line of output as a String
      java.lang.String readSymLink​(java.io.File path)
      Check if a file is a symbolic link and read it
      java.lang.String relativize​(java.lang.String base, java.lang.String other)
      java.io.File resolve​(java.io.File dir, java.lang.String name)
      Resolve this file to its actual path name that the JRE can use.
      abstract boolean retryFailedLockFileCommit()
      Does this file system have problems with atomic renames?
      ProcessResult runIfPresent​(Repository repository, Hook hook, java.lang.String[] args)
      Checks whether the given hook is defined for the given repository, then runs it with the given arguments.
      ProcessResult runIfPresent​(Repository repository, Hook hook, java.lang.String[] args, java.io.PrintStream outRedirect, java.io.PrintStream errRedirect, java.lang.String stdinArgs)
      Checks whether the given hook is defined for the given repository, then runs it with the given arguments.
      abstract java.lang.ProcessBuilder runInShell​(java.lang.String cmd, java.lang.String[] args)
      Initialize a ProcesssBuilder to run a command using the system shell.
      protected int runProcess​(java.lang.ProcessBuilder hookProcessBuilder, java.io.OutputStream outRedirect, java.io.OutputStream errRedirect, java.lang.String stdinArgs)
      Runs the given process until termination, clearing its stdout and stderr streams on-the-fly.
      protected static java.io.File searchPath​(java.lang.String path, java.lang.String... lookFor)
      Searches the given path to see if it contains one of the given files.
      abstract boolean setExecute​(java.io.File f, boolean canExec)
      Set a file to be executable by the user.
      FS setGitPrefix​(java.io.File path)
      Set the $prefix directory C Git uses.
      void setHidden​(java.io.File path, boolean hidden)
      Set the hidden attribute for file whose name starts with a period.
      void setLastModified​(java.io.File f, long time)
      Set the last modified time of a file system object.
      FS setUserHome​(java.io.File path)
      Set the user's home directory location.
      abstract boolean supportsExecute()
      Does this operating system and JRE support the execute flag on files?
      boolean supportsSymlinks()
      Does this operating system and JRE supports symbolic links.
      java.io.File userHome()
      Determine the user's home directory (location where preferences are).
      protected java.io.File userHomeImpl()
      Determine the user's home directory (location where preferences are).
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • DETECTED

        public static final FS DETECTED
        The auto-detected implementation selected for this operating system and JRE.
    • Constructor Detail

      • FS

        protected FS()
        Constructs a file system abstraction.
      • FS

        protected FS​(FS src)
        Initialize this FS using another's current settings.
        Parameters:
        src - the source FS to copy from.
    • Method Detail

      • detect

        public static FS detect()
        Auto-detect the appropriate file system abstraction.
        Returns:
        detected file system abstraction
      • detect

        public static FS detect​(java.lang.Boolean cygwinUsed)
        Auto-detect the appropriate file system abstraction, taking into account the presence of a Cygwin installation on the system. Using jgit in combination with Cygwin requires a more elaborate (and possibly slower) resolution of file system paths.
        Parameters:
        cygwinUsed -
        • Boolean.TRUE to assume that Cygwin is used in combination with jgit
        • Boolean.FALSE to assume that Cygwin is not used with jgit
        • null to auto-detect whether a Cygwin installation is present on the system and in this case assume that Cygwin is used
        Note: this parameter is only relevant on Windows.
        Returns:
        detected file system abstraction
      • newInstance

        public abstract FS newInstance()
        Returns:
        a new instance of the same type of FS.
      • supportsExecute

        public abstract boolean supportsExecute()
        Does this operating system and JRE support the execute flag on files?
        Returns:
        true if this implementation can provide reasonably accurate executable bit information; false otherwise.
      • supportsSymlinks

        public boolean supportsSymlinks()
        Does this operating system and JRE supports symbolic links. The capability to handle symbolic links is detected at runtime.
        Returns:
        true if symbolic links may be used
        Since:
        3.0
      • isCaseSensitive

        public abstract boolean isCaseSensitive()
        Is this file system case sensitive
        Returns:
        true if this implementation is case sensitive
      • canExecute

        public abstract boolean canExecute​(java.io.File f)
        Determine if the file is executable (or not).

        Not all platforms and JREs support executable flags on files. If the feature is unsupported this method will always return false.

        If the platform supports symbolic links and f is a symbolic link this method returns false, rather than the state of the executable flags on the target file.

        Parameters:
        f - abstract path to test.
        Returns:
        true if the file is believed to be executable by the user.
      • setExecute

        public abstract boolean setExecute​(java.io.File f,
                                           boolean canExec)
        Set a file to be executable by the user.

        Not all platforms and JREs support executable flags on files. If the feature is unsupported this method will always return false and no changes will be made to the file specified.

        Parameters:
        f - path to modify the executable status of.
        canExec - true to enable execution; false to disable it.
        Returns:
        true if the change succeeded; false otherwise.
      • lastModified

        public long lastModified​(java.io.File f)
                          throws java.io.IOException
        Get the last modified time of a file system object. If the OS/JRE support symbolic links, the modification time of the link is returned, rather than that of the link target.
        Parameters:
        f -
        Returns:
        last modified time of f
        Throws:
        java.io.IOException
        Since:
        3.0
      • setLastModified

        public void setLastModified​(java.io.File f,
                                    long time)
                             throws java.io.IOException
        Set the last modified time of a file system object. If the OS/JRE support symbolic links, the link is modified, not the target,
        Parameters:
        f -
        time -
        Throws:
        java.io.IOException
        Since:
        3.0
      • length

        public long length​(java.io.File path)
                    throws java.io.IOException
        Get the length of a file or link, If the OS/JRE supports symbolic links it's the length of the link, else the length of the target.
        Parameters:
        path -
        Returns:
        length of a file
        Throws:
        java.io.IOException
        Since:
        3.0
      • delete

        public void delete​(java.io.File f)
                    throws java.io.IOException
        Delete a file. Throws an exception if delete fails.
        Parameters:
        f -
        Throws:
        java.io.IOException - this may be a Java7 subclass with detailed information
        Since:
        3.3
      • resolve

        public java.io.File resolve​(java.io.File dir,
                                    java.lang.String name)
        Resolve this file to its actual path name that the JRE can use.

        This method can be relatively expensive. Computing a translation may require forking an external process per path name translated. Callers should try to minimize the number of translations necessary by caching the results.

        Not all platforms and JREs require path name translation. Currently only Cygwin on Win32 require translation for Cygwin based paths.

        Parameters:
        dir - directory relative to which the path name is.
        name - path name to translate.
        Returns:
        the translated path. new File(dir,name) if this platform does not require path name translation.
      • userHome

        public java.io.File userHome()
        Determine the user's home directory (location where preferences are).

        This method can be expensive on the first invocation if path name translation is required. Subsequent invocations return a cached result.

        Not all platforms and JREs require path name translation. Currently only Cygwin on Win32 requires translation of the Cygwin HOME directory.

        Returns:
        the user's home directory; null if the user does not have one.
      • setUserHome

        public FS setUserHome​(java.io.File path)
        Set the user's home directory location.
        Parameters:
        path - the location of the user's preferences; null if there is no home directory for the current user.
        Returns:
        this.
      • retryFailedLockFileCommit

        public abstract boolean retryFailedLockFileCommit()
        Does this file system have problems with atomic renames?
        Returns:
        true if the caller should retry a failed rename of a lock file.
      • userHomeImpl

        protected java.io.File userHomeImpl()
        Determine the user's home directory (location where preferences are).
        Returns:
        the user's home directory; null if the user does not have one.
      • searchPath

        protected static java.io.File searchPath​(java.lang.String path,
                                                 java.lang.String... lookFor)
        Searches the given path to see if it contains one of the given files. Returns the first it finds. Returns null if not found or if path is null.
        Parameters:
        path - List of paths to search separated by File.pathSeparator
        lookFor - Files to search for in the given path
        Returns:
        the first match found, or null
        Since:
        3.0
      • readPipe

        protected static java.lang.String readPipe​(java.io.File dir,
                                                   java.lang.String[] command,
                                                   java.lang.String encoding)
        Execute a command and return a single line of output as a String
        Parameters:
        dir - Working directory for the command
        command - as component array
        encoding -
        Returns:
        the one-line output of the command
      • gitPrefix

        public java.io.File gitPrefix()
        Returns:
        the $prefix directory C Git would use.
      • discoverGitPrefix

        protected abstract java.io.File discoverGitPrefix()
        Returns:
        the $prefix directory C Git would use.
      • setGitPrefix

        public FS setGitPrefix​(java.io.File path)
        Set the $prefix directory C Git uses.
        Parameters:
        path - the directory. Null if C Git is not installed.
        Returns:
        this
      • readSymLink

        public java.lang.String readSymLink​(java.io.File path)
                                     throws java.io.IOException
        Check if a file is a symbolic link and read it
        Parameters:
        path -
        Returns:
        target of link or null
        Throws:
        java.io.IOException
        Since:
        3.0
      • isSymLink

        public boolean isSymLink​(java.io.File path)
                          throws java.io.IOException
        Parameters:
        path -
        Returns:
        true if the path is a symbolic link (and we support these)
        Throws:
        java.io.IOException
        Since:
        3.0
      • exists

        public boolean exists​(java.io.File path)
        Tests if the path exists, in case of a symbolic link, true even if the target does not exist
        Parameters:
        path -
        Returns:
        true if path exists
        Since:
        3.0
      • isDirectory

        public boolean isDirectory​(java.io.File path)
        Check if path is a directory. If the OS/JRE supports symbolic links and path is a symbolic link to a directory, this method returns false.
        Parameters:
        path -
        Returns:
        true if file is a directory,
        Since:
        3.0
      • isFile

        public boolean isFile​(java.io.File path)
        Examine if path represents a regular file. If the OS/JRE supports symbolic links the test returns false if path represents a symbolic link.
        Parameters:
        path -
        Returns:
        true if path represents a regular file
        Since:
        3.0
      • isHidden

        public boolean isHidden​(java.io.File path)
                         throws java.io.IOException
        Parameters:
        path -
        Returns:
        true if path is hidden, either starts with . on unix or has the hidden attribute in windows
        Throws:
        java.io.IOException
        Since:
        3.0
      • setHidden

        public void setHidden​(java.io.File path,
                              boolean hidden)
                       throws java.io.IOException
        Set the hidden attribute for file whose name starts with a period.
        Parameters:
        path -
        hidden -
        Throws:
        java.io.IOException
        Since:
        3.0
      • createSymLink

        public void createSymLink​(java.io.File path,
                                  java.lang.String target)
                           throws java.io.IOException
        Create a symbolic link
        Parameters:
        path -
        target -
        Throws:
        java.io.IOException
        Since:
        3.0
      • relativize

        public java.lang.String relativize​(java.lang.String base,
                                           java.lang.String other)
        Parameters:
        base - The path against which other should be relativized.
        other - The path that will be made relative to base.
        Returns:
        A relative path that, when resolved against base, will yield the original other.
        Since:
        3.7
        See Also:
        FileUtils.relativize(String, String)
      • runIfPresent

        public ProcessResult runIfPresent​(Repository repository,
                                          Hook hook,
                                          java.lang.String[] args)
                                   throws JGitInternalException
        Checks whether the given hook is defined for the given repository, then runs it with the given arguments.

        The hook's standard output and error streams will be redirected to System.out and System.err respectively. The hook will have no stdin.

        Parameters:
        repository - The repository for which a hook should be run.
        hook - The hook to be executed.
        args - Arguments to pass to this hook. Cannot be null, but can be an empty array.
        Returns:
        The ProcessResult describing this hook's execution.
        Throws:
        JGitInternalException - if we fail to run the hook somehow. Causes may include an interrupted process or I/O errors.
        Since:
        3.7
      • runIfPresent

        public ProcessResult runIfPresent​(Repository repository,
                                          Hook hook,
                                          java.lang.String[] args,
                                          java.io.PrintStream outRedirect,
                                          java.io.PrintStream errRedirect,
                                          java.lang.String stdinArgs)
                                   throws JGitInternalException
        Checks whether the given hook is defined for the given repository, then runs it with the given arguments.
        Parameters:
        repository - The repository for which a hook should be run.
        hook - The hook to be executed.
        args - Arguments to pass to this hook. Cannot be null, but can be an empty array.
        outRedirect - A print stream on which to redirect the hook's stdout. Can be null, in which case the hook's standard output will be lost.
        errRedirect - A print stream on which to redirect the hook's stderr. Can be null, in which case the hook's standard error will be lost.
        stdinArgs - A string to pass on to the standard input of the hook. May be null.
        Returns:
        The ProcessResult describing this hook's execution.
        Throws:
        JGitInternalException - if we fail to run the hook somehow. Causes may include an interrupted process or I/O errors.
        Since:
        3.7
      • internalRunIfPresent

        protected ProcessResult internalRunIfPresent​(Repository repository,
                                                     Hook hook,
                                                     java.lang.String[] args,
                                                     java.io.PrintStream outRedirect,
                                                     java.io.PrintStream errRedirect,
                                                     java.lang.String stdinArgs)
                                              throws JGitInternalException
        See runIfPresent(Repository, Hook, String[], PrintStream, PrintStream, String) . Should only be called by FS supporting shell scripts execution.
        Parameters:
        repository - The repository for which a hook should be run.
        hook - The hook to be executed.
        args - Arguments to pass to this hook. Cannot be null, but can be an empty array.
        outRedirect - A print stream on which to redirect the hook's stdout. Can be null, in which case the hook's standard output will be lost.
        errRedirect - A print stream on which to redirect the hook's stderr. Can be null, in which case the hook's standard error will be lost.
        stdinArgs - A string to pass on to the standard input of the hook. May be null.
        Returns:
        The ProcessResult describing this hook's execution.
        Throws:
        JGitInternalException - if we fail to run the hook somehow. Causes may include an interrupted process or I/O errors.
        Since:
        3.7
      • findHook

        public java.io.File findHook​(Repository repository,
                                     Hook hook)
        Tries to find a hook matching the given one in the given repository.
        Parameters:
        repository - The repository within which to find a hook.
        hook - The hook we're trying to find.
        Returns:
        The File containing this particular hook if it exists in the given repository, null otherwise.
        Since:
        3.7
      • runProcess

        protected int runProcess​(java.lang.ProcessBuilder hookProcessBuilder,
                                 java.io.OutputStream outRedirect,
                                 java.io.OutputStream errRedirect,
                                 java.lang.String stdinArgs)
                          throws java.io.IOException,
                                 java.lang.InterruptedException
        Runs the given process until termination, clearing its stdout and stderr streams on-the-fly.
        Parameters:
        hookProcessBuilder - The process builder configured for this hook.
        outRedirect - A print stream on which to redirect the hook's stdout. Can be null, in which case the hook's standard output will be lost.
        errRedirect - A print stream on which to redirect the hook's stderr. Can be null, in which case the hook's standard error will be lost.
        stdinArgs - A string to pass on to the standard input of the hook. Can be null.
        Returns:
        the exit value of this hook.
        Throws:
        java.io.IOException - if an I/O error occurs while executing this hook.
        java.lang.InterruptedException - if the current thread is interrupted while waiting for the process to end.
        Since:
        3.7
      • runInShell

        public abstract java.lang.ProcessBuilder runInShell​(java.lang.String cmd,
                                                            java.lang.String[] args)
        Initialize a ProcesssBuilder to run a command using the system shell.
        Parameters:
        cmd - command to execute. This string should originate from the end-user, and thus is platform specific.
        args - arguments to pass to command. These should be protected from shell evaluation.
        Returns:
        a partially completed process builder. Caller should finish populating directory, environment, and then start the process.
      • getAttributes

        public FS.Attributes getAttributes​(java.io.File path)
        Parameters:
        path -
        Returns:
        the file attributes we care for
        Since:
        3.3
      • normalize

        public java.io.File normalize​(java.io.File file)
        Normalize the unicode path to composed form.
        Parameters:
        file -
        Returns:
        NFC-format File
        Since:
        3.3
      • normalize

        public java.lang.String normalize​(java.lang.String name)
        Normalize the unicode path to composed form.
        Parameters:
        name -
        Returns:
        NFC-format string
        Since:
        3.3