org.ka2ddo.yaac.os

Class OSAdapter

java.lang.Object

org.ka2ddo.yaac.os.OSAdapter

public abstract class OSAdapter
extends java.lang.Object

This abstract class provides service methods for accessing operating-system-specific information. No instances of this class should ever be instantiated, as all methods are static.

Author:

Andrew Pavlin, KA2DDO

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	OSAdapter.SerialPortListGetter Interface to a class that can provide a list of available serial ports on the host computer.

Method Summary

Modifier and Type	Method and Description
static java.lang.String[]	getCachedSerialPortNames(java.lang.String deviceName) Get the list of serial port device names, including the specified name.
static java.io.File	getDirectoryFromCache(java.lang.String cacheId) Get a File representing a remembered directory for a particular type of file operation.
static OSAdapter.SerialPortListGetter	getSerialPortListGetter() Get the existing SerialPortListGetter.
static java.lang.String[]	getSerialPortNames(java.lang.String currentDevName) Obtain the list of unused serial ports on this system.
static boolean	isWindows() Test if the host operating system is Microsoft Windows.
static void	markFileAsRandom(java.io.RandomAccessFile raf) If O/S and available libraries allow it, mark open file as only randomly accessed.
static void	markStreamAsSequential(java.io.FileInputStream is) If O/S and available libraries allow it, mark open file as only sequentially accessed.
static void	markStreamAsSequential(java.io.FileOutputStream os) If O/S and available libraries allow it, mark open file as only sequentially accessed.
static void	openURL(java.lang.String url) Launch O/S-specific browser to view a particular URL.
static void	purgeSerialPortCache() Purge the cached list of serial port device names, so the next query will have to build the list from scratch.
static void	putDirectoryToCache(java.lang.String cacheId, java.io.File dir) remember the last directory used for a type of file operation.
static long	releaseOldPages(java.io.FileInputStream is, long startForFlush) If O/S and available libraries allow it, mark every page prior to the current seek position as no longer needed.
static long	releaseOldPages(java.io.FileOutputStream os, long startForFlush) If O/S and available libraries allow it, mark every page prior to the current seek position as no longer needed.
static void	releaseOldPages(java.io.RandomAccessFile raf) If O/S and available libraries allow it, mark every page in the RandomAccessFile as no longer needed.
static void	releaseOldPages(java.io.RandomAccessFile raf, long startPos, long endPos) If O/S and available libraries allow it, mark every page in the specified range in the RandomAccessFile as no longer needed.
static void	sendEmail(java.lang.String emailAddr) Launch O/S-specific email client to compose an outgoing email.
static void	setSerialPortListGetter(OSAdapter.SerialPortListGetter serialPortListGetter) Replace the SerialPortListGetter with a different one if the serial port library is changed by a plugin.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getSerialPortListGetter

public static OSAdapter.SerialPortListGetter getSerialPortListGetter()

Get the existing SerialPortListGetter.

Returns:

SerialPortListGetter currently in use

setSerialPortListGetter

public static void setSerialPortListGetter(OSAdapter.SerialPortListGetter serialPortListGetter)

Replace the SerialPortListGetter with a different one if the serial port library is changed by a plugin. Should only be called by plugins.

Parameters:

serialPortListGetter - SerialPortListGetter instance

getSerialPortNames

public static java.lang.String[] getSerialPortNames(java.lang.String currentDevName)

Obtain the list of unused serial ports on this system.

Parameters:

currentDevName - String of an already-busy device name to add to list, or null for no additional name

Returns:

array String device names, or null if the system does not have access to serial ports

getCachedSerialPortNames

public static java.lang.String[] getCachedSerialPortNames(java.lang.String deviceName)

Get the list of serial port device names, including the specified name.

Parameters:

deviceName - device name to include (in case the device is already open)

Returns:

array of device name Strings

purgeSerialPortCache

public static void purgeSerialPortCache()

Purge the cached list of serial port device names, so the next query will have to build the list from scratch.

isWindows

public static boolean isWindows()

Test if the host operating system is Microsoft Windows.

Returns:

boolean true if running on Microsoft Windows (any release), false for any other operating system

openURL

public static void openURL(java.lang.String url)

Launch O/S-specific browser to view a particular URL. Must be called from AWT dispatch thread.

Parameters:

url - String representation of URL to view

sendEmail

public static void sendEmail(java.lang.String emailAddr)
                      throws java.lang.Throwable

Launch O/S-specific email client to compose an outgoing email. Must be called from AWT dispatch thread.

Parameters:

emailAddr - String representation of recipient email address

Throws:

java.lang.Throwable - if email client could not be launched for any reason

getDirectoryFromCache

public static java.io.File getDirectoryFromCache(java.lang.String cacheId)

Get a File representing a remembered directory for a particular type of file operation.

Parameters:

cacheId - String name of file operation (such as log files, or tile files)

Returns:

File pointing at the last directory for such operations, or null if never yet cached

putDirectoryToCache

public static void putDirectoryToCache(java.lang.String cacheId,
                                       java.io.File dir)

remember the last directory used for a type of file operation.

Parameters:

cacheId - String name of file type

dir - File pointing to the last directory used for those files

markStreamAsSequential

public static void markStreamAsSequential(java.io.FileInputStream is)

If O/S and available libraries allow it, mark open file as only sequentially accessed.

Parameters:

is - FileInputStream whose file descriptor will be accessed

releaseOldPages

public static long releaseOldPages(java.io.FileInputStream is,
                                   long startForFlush)

If O/S and available libraries allow it, mark every page prior to the current seek position as no longer needed.

Parameters:

is - FileInputStream whose file descriptor will be accessed

startForFlush - file position where no-longer-needed file system cache pages should start being released

Returns:

file position where pages stopped being released

releaseOldPages

public static long releaseOldPages(java.io.FileOutputStream os,
                                   long startForFlush)

If O/S and available libraries allow it, mark every page prior to the current seek position as no longer needed.

Parameters:

os - FileOutputStream whose file descriptor will be accessed

startForFlush - file position where no-longer-needed file system cache pages should start being released

Returns:

file position where pages stopped being released

releaseOldPages

public static void releaseOldPages(java.io.RandomAccessFile raf)

If O/S and available libraries allow it, mark every page in the RandomAccessFile as no longer needed. Note that any user-mode cached data should be flushed to the operating system kernel prior to calling this method.

Parameters:

raf - RandomAccessFile whose file descriptor will be accessed

See Also:

MultiBufferedRandomAccessFile.getRandomAccessFile()

releaseOldPages

public static void releaseOldPages(java.io.RandomAccessFile raf,
                                   long startPos,
                                   long endPos)

If O/S and available libraries allow it, mark every page in the specified range in the RandomAccessFile as no longer needed. Note that any user-mode cached data should be flushed to the operating system kernel prior to calling this method.

Parameters:

raf - RandomAccessFile whose file descriptor will be accessed

startPos - starting offset in file to release

endPos - ending offset in file to release

See Also:

MultiBufferedRandomAccessFile.getRandomAccessFile()

markStreamAsSequential

public static void markStreamAsSequential(java.io.FileOutputStream os)

If O/S and available libraries allow it, mark open file as only sequentially accessed.

Parameters:

os - FileOutputStream whose file descriptor will be accessed

markFileAsRandom

public static void markFileAsRandom(java.io.RandomAccessFile raf)

If O/S and available libraries allow it, mark open file as only randomly accessed.

Parameters:

raf - RandomAccessFile whose file descriptor will be accessed