Package org.apache.bookkeeper.util

Class HardLink.HardLinkCGUnix

java.lang.Object

org.apache.bookkeeper.util.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

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.