Class HardLink.HardLinkCGUnix

  • Enclosing class:
    HardLink

    static class HardLink.HardLinkCGUnix
    extends java.lang.Object
    Implementation of HardLinkCommandGetter class for Unix.
    • Constructor Summary

      Constructors 
      Constructor Description
      HardLinkCGUnix()  
    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      (package private) int getLinkMultArgLength​(java.io.File fileDir, java.lang.String[] fileBaseNames, java.io.File linkDir)
      Calculate the total string length of the shell command resulting from execution of linkMult, plus the length of the source directory name (which will also be provided to the shell).
      (package private) int getMaxAllowedCmdArgLength()
      Get the maximum allowed string length of a shell command on this OS, which is just the documented minimum guaranteed supported command length - aprx.
      (package private) java.lang.String[] linkCount​(java.io.File file)
      Get the command string to query the hardlink count of a file.
      (package private) java.lang.String[] linkMult​(java.lang.String[] fileBaseNames, java.io.File linkDir)
      Get the command string needed to hardlink a bunch of files from a single source directory into a target directory.
      (package private) java.lang.String[] linkOne​(java.io.File file, java.io.File linkName)
      Get the command string needed to hardlink a single file.
      • Methods inherited from class java.lang.Object

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

      • HardLinkCGUnix

        HardLinkCGUnix()
    • Method Detail

      • linkOne

        java.lang.String[] linkOne​(java.io.File file,
                                   java.io.File linkName)
                            throws java.io.IOException
        Get the command string needed to hardlink a single file.
        Throws:
        java.io.IOException
      • linkMult

        java.lang.String[] linkMult​(java.lang.String[] fileBaseNames,
                                    java.io.File linkDir)
                             throws java.io.IOException
        Get the command string needed to hardlink a bunch of files from a single source directory into a target directory. The source directory is not specified here, but the command will be executed using the source directory as the "current working directory" of the shell invocation.
        Parameters:
        fileBaseNames - - array of path-less file names, relative to the source directory
        linkDir - - target directory where the hardlinks will be put
        Returns:
        - an array of Strings suitable for use as a single shell command with Runtime.exec()
        Throws:
        java.io.IOException - - if any of the file or path names misbehave
      • linkCount

        java.lang.String[] linkCount​(java.io.File file)
                              throws java.io.IOException
        Get the command string to query the hardlink count of a file.
        Throws:
        java.io.IOException
      • getLinkMultArgLength

        int getLinkMultArgLength​(java.io.File fileDir,
                                 java.lang.String[] fileBaseNames,
                                 java.io.File linkDir)
                          throws java.io.IOException
        Calculate the total string length of the shell command resulting from execution of linkMult, plus the length of the source directory name (which will also be provided to the shell).
        Parameters:
        fileDir - - source directory, parent of fileBaseNames
        fileBaseNames - - array of path-less file names, relative to the source directory
        linkDir - - target directory where the hardlinks will be put
        Returns:
        - total data length (must not exceed maxAllowedCmdArgLength)
        Throws:
        java.io.IOException
      • getMaxAllowedCmdArgLength

        int getMaxAllowedCmdArgLength()
        Get the maximum allowed string length of a shell command on this OS, which is just the documented minimum guaranteed supported command length - aprx. 32KB for Unix, and 8KB for Windows.