resource observer now uses the Java 6 method to check for free space. thus, disk observing now needs Java 6 installed.

git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@6652 6c8d7289-2bf4-0310-a012-ef5d649a1542
This commit is contained in:
lotus 2010-02-06 18:48:06 +00:00
parent 089877f32c
commit 11188cd7eb
3 changed files with 112 additions and 554 deletions

View File

@ -135,12 +135,12 @@ public class Status {
// resource observer status
if (adminaccess) {
if (!sb.observer.getDisksOK()){
if (!sb.observer.getDiskAvailable()){
final String minFree = Formatter.bytesToString(sb.observer.getMinFreeDiskSpace());
prop.put("warningDiskSpaceLow", "1");
prop.put("warningDiskSpaceLow_minSpace", minFree);
}
if (!sb.observer.getMemoryOK()){
if (!sb.observer.getMemoryAvailable()){
final String minFree = Formatter.bytesToString(sb.observer.getMinFreeMemory() * 1024L);
prop.put("warningMemoryLow", "1");
prop.put("warningMemoryLow_minSpace", minFree);

View File

@ -1,10 +1,12 @@
// ResourceObserver.java
// -----------------------
// part of YaCy
// (C) by Detlef Reichl; detlef!reichl()gmx!org
// (c) David Wieditz; lotus at mail.berlios.de
// first published 6.2.2010
//
// based on the former code (c) by Detlef Reichl; detlef!reichl()gmx!org
// Pforzheim, Germany, 2008
//
// changes by David Wieditz
// part of YaCy
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
@ -22,84 +24,39 @@
package de.anomic.crawler;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.io.File;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import net.yacy.kelondro.logging.Log;
import net.yacy.kelondro.util.DiskSpace;
import net.yacy.kelondro.util.MemoryControl;
import de.anomic.search.Switchboard;
import de.anomic.search.SwitchboardConstants;
public final class ResourceObserver {
// Unknown for now
//private static final static long MIN_FREE_MEMORY = 0;
// We are called with the cleanup job every five minutes;
// the disk usage should be checked with every run
private static final int CHECK_DISK_USAGE_FREQ = 1;
// The memory usage should be checked on every run
private static final int CHECK_MEMORY_USAGE_FREQ = 1;
public class ResourceObserver {
public static final Log log = new Log("RESOURCE OBSERVER");
// return values for available disk/memory
private static final int LOW = 0;
private static final int MEDIUM = 1;
private static final int HIGH = 2;
public static final Log log = new Log("RESOURCE OBSERVER");
private final Switchboard sb;
private final File path; // path to check
private int checkDiskUsageCount;
private int checkMemoryUsageCount;
private int disksFree;
private int memoryFree;
private int normalizedDiskFree = HIGH;
private int normalizedMemoryFree = HIGH;
private boolean disabledDHT = false;
/**
* The ResourceObserver checks the resources
* and pauses crawls if necessary
* @param sb the plasmaSwitchboard
*/
public ResourceObserver(final Switchboard sb) {
this.sb = sb;
log.logInfo("initializing the resource observer");
final ArrayList<String> pathsToCheck = new ArrayList<String>();
// FIXME whats about the secondary path???
// = (getConfig(plasmaSwitchboard.INDEX_SECONDARY_PATH, "");
final String[] pathes = {
SwitchboardConstants.HTDOCS_PATH,
SwitchboardConstants.INDEX_PRIMARY_PATH,
SwitchboardConstants.LISTS_PATH,
SwitchboardConstants.RANKING_PATH,
SwitchboardConstants.WORK_PATH};
String path;
for (final String element : pathes) {
try {
path = sb.getConfigPath(element, "").getCanonicalPath();
if (path.length() > 0) pathsToCheck.add(path);
} catch (final IOException e) {}
}
DiskSpace.init(pathsToCheck);
if (!DiskSpace.isUsable())
log.logWarning("Disk usage returned: " + DiskSpace.getErrorMessage());
checkDiskUsageCount = 0;
checkMemoryUsageCount = 0;
disksFree = HIGH;
memoryFree = HIGH;
this.path = sb.getConfigPath(SwitchboardConstants.INDEX_PRIMARY_PATH, "");
}
public static void initThread() {
Switchboard sb = Switchboard.getSwitchboard();
// initializing the resourceObserver
sb.observer = new ResourceObserver(sb);
// run the oberver here a first time
final Switchboard sb = Switchboard.getSwitchboard();
sb.observer = new ResourceObserver(Switchboard.getSwitchboard());
sb.observer.resourceObserverJob();
}
@ -109,77 +66,94 @@ public final class ResourceObserver {
public void resourceObserverJob() {
MemoryControl.setDHTkbytes(getMinFreeMemory());
checkDiskUsageCount++;
checkMemoryUsageCount++;
int tmpDisksFree = HIGH;
int tmpMemoryFree = HIGH;
if (checkDiskUsageCount >= CHECK_DISK_USAGE_FREQ) {
checkDiskUsageCount = 0;
tmpDisksFree = checkDisks();
disksFree = tmpDisksFree;
}
if (checkMemoryUsageCount >= CHECK_MEMORY_USAGE_FREQ) {
checkMemoryUsageCount = 0;
tmpMemoryFree = checkMemory();
memoryFree = tmpMemoryFree;
}
normalizedDiskFree = getNormalizedDiskFree();
normalizedMemoryFree = getNormalizedMemoryFree();
if (tmpDisksFree < HIGH || tmpMemoryFree < HIGH) {
if (tmpDisksFree < HIGH && !sb.crawlJobIsPaused(SwitchboardConstants.CRAWLJOB_LOCAL_CRAWL)) {
log.logInfo("pausing local crawls");
sb.pauseCrawlJob(SwitchboardConstants.CRAWLJOB_LOCAL_CRAWL);
}
if (tmpDisksFree < HIGH && !sb.crawlJobIsPaused(SwitchboardConstants.CRAWLJOB_REMOTE_TRIGGERED_CRAWL)) {
log.logInfo("pausing remote triggered crawls");
sb.pauseCrawlJob(SwitchboardConstants.CRAWLJOB_REMOTE_TRIGGERED_CRAWL);
}
if ((tmpDisksFree == LOW || tmpMemoryFree < HIGH) && sb.getConfigBool(SwitchboardConstants.INDEX_RECEIVE_ALLOW, false)) {
log.logInfo("disabling index receive");
sb.setConfig(SwitchboardConstants.INDEX_RECEIVE_ALLOW, false);
sb.peers.mySeed().setFlagAcceptRemoteIndex(false);
disabledDHT = true;
}
}
else {
if (DiskSpace.isUsable()) {
if(disabledDHT) { // we were wrong!
log.logInfo("enabling index receive");
sb.setConfig(SwitchboardConstants.INDEX_RECEIVE_ALLOW, true);
sb.peers.mySeed().setFlagAcceptRemoteIndex(true);
disabledDHT = false;
}
log.logInfo("run completed; everything in order");
}
else
log.logInfo("The observer is out of order: " + DiskSpace.getErrorMessage());
}
if (normalizedDiskFree < HIGH || normalizedMemoryFree < HIGH) {
if (normalizedDiskFree < HIGH) { // pause crawls
if (!sb.crawlJobIsPaused(SwitchboardConstants.CRAWLJOB_LOCAL_CRAWL)) {
log.logInfo("pausing local crawls");
sb.pauseCrawlJob(SwitchboardConstants.CRAWLJOB_LOCAL_CRAWL);
}
if (!sb.crawlJobIsPaused(SwitchboardConstants.CRAWLJOB_REMOTE_TRIGGERED_CRAWL)) {
log.logInfo("pausing remote triggered crawls");
sb.pauseCrawlJob(SwitchboardConstants.CRAWLJOB_REMOTE_TRIGGERED_CRAWL);
}
}
if ((normalizedDiskFree == LOW || normalizedMemoryFree < HIGH) && sb.getConfigBool(SwitchboardConstants.INDEX_RECEIVE_ALLOW, false)) {
log.logInfo("disabling index receive");
sb.setConfig(SwitchboardConstants.INDEX_RECEIVE_ALLOW, false);
sb.peers.mySeed().setFlagAcceptRemoteIndex(false);
disabledDHT = true;
}
}
else {
if(disabledDHT) { // we were wrong!
log.logInfo("enabling index receive");
sb.setConfig(SwitchboardConstants.INDEX_RECEIVE_ALLOW, true);
sb.peers.mySeed().setFlagAcceptRemoteIndex(true);
disabledDHT = false;
}
log.logInfo("resources ok");
}
}
/**
* returns the amount of disk space available
* @return <ul>
* <li><code>HIGH</code> if disk space is available</li>
* <li><code>MEDIUM</code> if low disk space is available</li>
* <li><code>LOW</code> if lower than hardlimit disk space is available</li>
* </ul>
*/
private int getNormalizedDiskFree() {
final long currentSpace = getUsableSpace(this.path);
if(currentSpace < 1L) return HIGH;
int ret = HIGH;
if (currentSpace < getMinFreeDiskSpace()) {
log.logWarning("Volume " + this.path.toString() + ": free space (" + (currentSpace / 1024 / 1024) + " MB) is too low (< " + (getMinFreeDiskSpace() / 1024 / 1024) + " MB)");
ret = MEDIUM;
}
if (currentSpace < getMinFreeDiskSpace_hardlimit()) {
ret = LOW;
}
return ret;
}
private int getNormalizedMemoryFree() {
if(!MemoryControl.getDHTallowed()) return LOW;
return HIGH;
}
/**
* @return <code>true</code> if disk space is available
*/
public boolean getDisksOK () {
return disksFree == HIGH;
public boolean getDiskAvailable() {
return normalizedDiskFree == HIGH;
}
/**
* @return <code>true</code> if memory is available
*/
public boolean getMemoryOK () {
return memoryFree == HIGH;
public boolean getMemoryAvailable() {
return normalizedMemoryFree == HIGH;
}
/**
* @return amount of space (bytes) that should be kept free
*/
public long getMinFreeDiskSpace () {
public long getMinFreeDiskSpace() {
return sb.getConfigLong(SwitchboardConstants.DISK_FREE, 3000) /* MiB */ * 1024L * 1024L;
}
/**
* @return amount of space (bytes) that should at least be kept free
*/
public long getMinFreeDiskSpace_hardlimit () {
public long getMinFreeDiskSpace_hardlimit() {
return sb.getConfigLong(SwitchboardConstants.DISK_FREE_HARDLIMIT, 100) /* MiB */ * 1024L * 1024L;
}
@ -190,39 +164,25 @@ public final class ResourceObserver {
return sb.getConfigLong(SwitchboardConstants.MEMORY_ACCEPTDHT, 0);
}
/**
* returns the amount of disk space available
* @return <ul>
* <li><code>HIGH</code> if disk space is available</li>
* <li><code>MEDIUM</code> if low disk space is available</li>
* <li><code>LOW</code> if lower than hardlimit or 1/5 disk space is available (the max)</li>
* </ul>
*/
private int checkDisks() {
int ret = HIGH;
if (!DiskSpace.isUsable ())
return HIGH;
/**
* This method calls File.getUsableSpace() from Java 6.
* @param file the path to be checked
* @return "The number of available bytes on the partition or 0L if the abstract pathname does not name a partition." -1L on error.
* @author lotus at mail.berlios.de
*/
public static long getUsableSpace(final File file) {
try {
final Class<?> File6 = Class.forName("java.io.File");
final Class<?>[] param = {File.class, String.class };
final Constructor<?> File6Constructor = File6.getConstructor(param);
final Object file6 = File6Constructor.newInstance(file, "");
final Method getFreeSpace = file6.getClass().getMethod("getUsableSpace", (Class[])null);
final Object space = getFreeSpace.invoke(file6, (Object[])null);
return Long.parseLong(space.toString());
} catch (Throwable e) {
return -1L;
}
}
final HashMap<String, long[]> usage = DiskSpace.getDiskUsage();
long[] val;
for (final Map.Entry<String, long[]> entry: usage.entrySet()) {
val = entry.getValue();
log.logInfo("df of Volume " + entry.getKey() + ": " + (val[1] / 1024 / 1024) + " MB");
if (val[1] < getMinFreeDiskSpace()) {
log.logWarning("Volume " + entry.getKey() + ": free space (" + (val[1] / 1024 / 1024) + " MB) is too low (< " + (getMinFreeDiskSpace() / 1024 / 1024) + " MB)");
ret = MEDIUM;
}
if (val[1] < Math.max(getMinFreeDiskSpace() / 5L, getMinFreeDiskSpace_hardlimit())) {
ret = LOW;
}
}
return ret;
}
private int checkMemory() {
if(!MemoryControl.getDHTallowed()) return LOW;
return HIGH;
}
}

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@ -1,402 +0,0 @@
// diskUsage.java
// -----------------------
// part of YaCy
// (C) by Detlef Reichl; detlef!reichl()gmx!org
// Pforzheim, Germany, 2008
//
// [MC] made many changes to remove side-effect-based routines towards a more functional programming style
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
// The HashMap contains the following values:
//
// key = the device name e.g. /dev/hda1, on windows the drive e.g. c:
// value[0] = the total space of the volume, on windows not used
// value[1] = the free space of the volume
package net.yacy.kelondro.util;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import net.yacy.kelondro.logging.Log;
public class DiskSpace {
private static Log log = new Log("DISK USAGE");
private static final List<String> allVolumes = new ArrayList<String>();
private static final List<String> allMountPoints = new ArrayList<String>();
private static final List<Boolean> usedVolumes = new ArrayList<Boolean>();
private static final List<String> yacyUsedVolumes = new ArrayList<String>();
private static final List<String> yacyUsedMountPoints = new ArrayList<String>();
private static int usedOS = -1;
private static String usageError = null;
private static String windowsCommand = null;
// Unix-like
private static final int AIX = 0; // IBM
private static final int BS2000 = 1; // Fujitsu Siemens (oficial BS2000/OSD)
//private static final int BSD = 2; // all kind of BSD
private static final int HAIKU = 3; // like BeOS; does not have a JRE til now, but they are working on it
//private static final int HP_UX = 4; // Hewlett-Packard
private static final int TRU64 = 5; // Hewlett-Packard
//private static final int IRIX = 6; // sgi
private static final int LINUX = 7; // all kind of linux
//private static final int MAC_OS_X = 8; // Apple
private static final int MINIX = 9; // don't know if there even is a JRE for minix...
//private static final int SOLARIS = 10; // SUN
//private static final int SUNOS = 11; // The latest SunOS version is from 1990 but the Solaris java refferer remains SunOS
private static final int UNICOS = 12; // cray
private static final int UNIX_END = UNICOS;
// Windows dos based
//private static final int WINDOWS_95 = 13;
//private static final int WINDOWS_98 = 14;
//private static final int WINDOWS_ME = 15;
// Windows WinNT based
//private static final int WINDOWS_NT = 16;
//private static final int WINDOWS_2000 = 17;
//private static final int WINDOWS_XP = 18;
//private static final int WINDOWS_SERVER = 19;
//private static final int WINDOWS_VISTA = 20;
//private static final int WINDOWS_7 = 21;
// don't change order of names!
// (look above)
private static final String[] OSname = {
"aix", "bs2000", "bsd", "haiku", "hp-ux", "tru64", "irix", "linux", "mac os x", "minix",
"solaris", "sunos", "unicos",
"windows 95", "windows 98", "windows me",
"windows nt", "windows 2000", "windows xp", "windows server", "windows vista", "windows 7"};
//////////////////
// public API //
//////////////////
public static void init(final ArrayList<String> pathsToCheck) {
if (usedOS >= 0) return; // prevent double initialization
usedOS = getOS();
if (usedOS == -1) {
return;
}
usageError = null;
if (usedOS <= UNIX_END) {
// some kind of *nix
dfUnixGetVolumes();
for (int i = 0; i < allMountPoints.size(); i++)
usedVolumes.add(false);
checkVolumesInUseUnix ("DATA");
checkMappedSubDirs(pathsToCheck);
for (int i = 0; i < allVolumes.size(); i++){
if (usedVolumes.get(i)) {
yacyUsedVolumes.add(allVolumes.get (i));
yacyUsedMountPoints.add(allMountPoints.get (i));
}
}
} else {
// all Windows versions
initWindowsCommandVersion();
checkStartVolume();
checkMappedSubDirs(pathsToCheck);
}
if (yacyUsedVolumes.size() < 1)
usageError = "found no volumes";
}
public static HashMap<String, long[]> getDiskUsage () {
if (usageError != null) return null;
if (usedOS <= UNIX_END)
return dfUnix();
else
return dfWindows();
}
public static boolean isUsable() {
return usageError == null;
}
public static int getNumUsedVolumes () {
return yacyUsedVolumes.size();
}
public static String getErrorMessage() {
return usageError;
}
////////////
// Unix //
////////////
private static HashMap<String, long[]> dfUnix() {
final HashMap<String, long[]> diskUsages = new HashMap<String, long[]>();
try {
final List<String> lines = dfUnixExec();
nextLine: for (final String line: lines){
if (line.length() > 0 && line.charAt(0) != '/') continue;
final String[] tokens = line.split(" +", 6);
if (tokens.length < 6) continue;
for (int i = 0; i < yacyUsedVolumes.size(); i++){
if (yacyUsedVolumes.get(i).equals(tokens[0])) {
final long[] vals = new long[2];
try { vals[0] = Long.valueOf(tokens[1]); } catch (final NumberFormatException e) { continue nextLine; }
try { vals[1] = Long.valueOf(tokens[3]); } catch (final NumberFormatException e) { continue nextLine; }
vals[0] *= 1024;
vals[1] *= 1024;
diskUsages.put(yacyUsedMountPoints.get(i), vals);
}
}
}
return diskUsages;
} catch (final IOException e) {
usageError = "dfUnix: " + e.getMessage();
return diskUsages;
}
}
private static void dfUnixGetVolumes() {
try {
final List<String> lines = dfUnixExec();
nextLine: for (final String line: lines){
if (line.length() > 0 && line.charAt(0) != '/') continue;
final String[] tokens = line.split(" +", 6);
if (tokens.length < 6) continue;
for (int i = 0; i < allMountPoints.size(); i++) {
if (tokens[5].trim().compareTo(allMountPoints.get(i)) > 0) {
allMountPoints.add(i, tokens[5].trim());
allVolumes.add(i, tokens[0]);
continue nextLine;
}
}
allMountPoints.add(allMountPoints.size(), tokens[5]);
allVolumes.add(allVolumes.size(), tokens[0]);
}
} catch (final IOException e) {
usageError = "error during dfUnixGetVolumes: " + e.getMessage();
}
}
private static List<String> dfUnixExec() throws IOException {
// -k set blocksize to 1024
// confirmed with tests:
// Linux
// verified with man pages or other docs:
// AIX, BS2000, *BSD, HP-UX, IRIX, minix, Mac OS X, Solaris, Tru64, UNICOS
// -l list local filesystems only
// confirmed with tests:
// Linux
// verified with man pages or other docs:
// AIX, BS2000, *BSD, HP-UX, IRIX, minix, Mac OS X, Solaris, UNICOS
// please report all successes or fails for non-confirmed systems to
// detlef!reichl()gmx!org. Thanks!
final List<String> processArgs = new ArrayList<String>();
processArgs.add("df");
processArgs.add("-k");
// Some systems need the additional -P parameter to return the data in Posix format.
// Without it the mount point will be in the 7th and not in the 6th column
// On Linux, -P is used to have everything on one line, for lvm or based setup
if (usedOS == AIX || usedOS == BS2000 || usedOS == MINIX || usedOS == UNICOS || usedOS == LINUX)
processArgs.add("-P");
// Tru64 does not know the -l parameter
// For haiku i didn't found online docs at all; so better exclude it
if (usedOS != TRU64 && usedOS != HAIKU)
processArgs.add("-l");
final List<String> lines = ConsoleInterface.getConsoleOutput(processArgs, log);
return lines;
}
private static void checkVolumesInUseUnix (final String path) {
final File file = new File(path);
final File[] fileList = file.listFiles();
if (fileList == null) {
// the file is not a directory
return;
}
String base;
String dir;
for (final File element : fileList) {
if (element.isDirectory()) {
try {
dir = element.getCanonicalPath();
} catch (final IOException e) {
usageError = "checkVolumesInUseUnix(1): " + e.getMessage();
break;
}
if (dir.endsWith ("HTCACHE")
|| dir.endsWith ("HTDOCS")
|| dir.endsWith ("LOCALE")
|| dir.endsWith ("RANKING")
|| dir.endsWith ("RELEASE")
|| dir.endsWith ("collection.0028.commons")) {
checkPathUsageUnix (dir);
} else if (dir != null) {
checkVolumesInUseUnix (dir);
} else {
log.logSevere("directory is null: " + element);
}
} else {
try {
base = element.getCanonicalPath();
} catch (final IOException e) {
usageError = "checkVolumesInUseUnix(2): " + e.getMessage();
break;
}
checkPathUsageUnix (base);
}
}
}
///////////////
// Windows //
///////////////
private static void initWindowsCommandVersion () {
windowsCommand = null;
final String os = System.getProperty("os.name").toLowerCase();
final String[] oses = {"windows 95", "windows 98", "windows me"};
for (final String element : oses) {
if (os.indexOf(element) >= 0){
windowsCommand = "command.com";
break;
}
}
if (windowsCommand == null)
windowsCommand = "cmd.exe";
}
private static void checkStartVolume() {
final File file = new File("DATA");
String path = null;
try { path = file.getCanonicalPath(); } catch (final IOException e) {
usageError = "Cant get DATA directory";
return;
}
if (path.length() < 6)
return;
yacyUsedVolumes.add(path);
}
private static HashMap<String, long[]> dfWindows() {
final HashMap<String, long[]> diskUsages = new HashMap<String, long[]>();
for (int i = 0; i < yacyUsedVolumes.size(); i++){
final List<String> processArgs = new ArrayList<String>();
processArgs.add(windowsCommand);
processArgs.add("/c");
processArgs.add("dir");
processArgs.add("\"" + yacyUsedVolumes.get(i) + "\"");
try {
final List<String> lines = ConsoleInterface.getConsoleOutput(processArgs, log);
String line = "";
for (int l = lines.size() - 1; l >= 0; l--) {
line = lines.get(l).trim();
if (line.length() > 0) break;
}
if (line.length() == 0) {
usageError = "unable to get free size of volume " + yacyUsedVolumes.get(i);
return diskUsages;
}
final String[] tokens = line.trim().split(" ++");
final long[] vals = new long[2];
vals[0] = -1;
try { vals[1] = Long.valueOf(tokens[2].replaceAll("[.,]", "")); } catch (final NumberFormatException e) {continue;}
diskUsages.put (yacyUsedVolumes.get(i), vals);
} catch (final IOException e) {
usageError = "dfWindows: " + e.getMessage();
return diskUsages;
}
}
return diskUsages;
}
/////////////
// common //
/////////////
private static int getOS() {
final String os = System.getProperty("os.name").toLowerCase();
for (int i = 0; i < OSname.length; i++)
{
if (os.indexOf(OSname[i]) >= 0)
return i;
}
usageError = "unknown operating system (" + System.getProperty("os.name") + ")";
return -1;
}
private static void checkMappedSubDirs (final ArrayList<String> pathsToCheck) {
for (final String path : pathsToCheck) {
if (usedOS <= UNIX_END)
checkPathUsageUnix (path);
else
checkPathUsageWindows (path);
}
}
private static void checkPathUsageUnix (final String path) {
for (int i = 0; i < allMountPoints.size(); i++){
if (path.startsWith (allMountPoints.get(i))) {
usedVolumes.set(i, true);
return;
}
}
}
private static void checkPathUsageWindows(final String path) {
// we would need to ask every path by "dir" as asking the root is not hardlink-proof:
// yacyUsedVolumes.add(path);
return;
/*
int index = -1;
final String sub = path.substring(0, 1); // ?? nur ein character?
try {
index = yacyUsedVolumes.indexOf(sub);
} catch (final IndexOutOfBoundsException e) {
usageError = "internal error while checking used windows volumes";
return;
}
if (index < 0)
yacyUsedVolumes.add(sub);
*/
}
}