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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
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*
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package sun.jvmstat.perfdata.monitor.protocol.local;
import sun.jvmstat.monitor.*;
import sun.jvmstat.monitor.event.*;
import java.util.*;
import java.util.regex.*;
import java.io.*;
/**
* Class for managing the LocalMonitoredVm instances on the local system.
* <p>
* This class is responsible for the mechanism that detects the active
* HotSpot Java Virtual Machines on the local host and possibly for a
* specific user. The ability to detect all possible HotSpot Java Virtual
* Machines on the local host may be limited by the permissions of the
* principal running this JVM.
*
* @author Brian Doherty
* @since 1.5
*/
public class LocalVmManager {
private String userName; // user name for monitored jvm
private File tmpdir;
private Pattern userPattern;
private Matcher userMatcher;
private FilenameFilter userFilter;
private Pattern filePattern;
private Matcher fileMatcher;
private FilenameFilter fileFilter;
private Pattern tmpFilePattern;
private Matcher tmpFileMatcher;
private FilenameFilter tmpFileFilter;
/**
* Creates a LocalVmManager instance for the local system.
* <p>
* Manages LocalMonitoredVm instances for which the principal
* has appropriate permissions.
*/
public LocalVmManager() {
this(null);
}
/**
* Creates a LocalVmManager instance for the given user.
* <p>
* Manages LocalMonitoredVm instances for all JVMs owned by the specified
* user.
*
* @param user the name of the user
*/
public LocalVmManager(String user) {
this.userName = user;
if (userName == null) {
tmpdir = new File(PerfDataFile.getTempDirectory());
userPattern = Pattern.compile(PerfDataFile.userDirNamePattern);
userMatcher = userPattern.matcher("");
userFilter = new FilenameFilter() {
public boolean accept(File dir, String name) {
userMatcher.reset(name);
return userMatcher.lookingAt();
}
};
} else {
tmpdir = new File(PerfDataFile.getTempDirectory(userName));
}
filePattern = Pattern.compile(PerfDataFile.fileNamePattern);
fileMatcher = filePattern.matcher("");
fileFilter = new FilenameFilter() {
public boolean accept(File dir, String name) {
fileMatcher.reset(name);
return fileMatcher.matches();
}
};
tmpFilePattern = Pattern.compile(PerfDataFile.tmpFileNamePattern);
tmpFileMatcher = tmpFilePattern.matcher("");
tmpFileFilter = new FilenameFilter() {
public boolean accept(File dir, String name) {
tmpFileMatcher.reset(name);
return tmpFileMatcher.matches();
}
};
}
/**
* Return the current set of monitorable Java Virtual Machines.
* <p>
* The set returned by this method depends on the user name passed
* to the constructor. If no user name was specified, then this
* method will return all candidate JVMs on the system. Otherwise,
* only the JVMs for the given user will be returned. This assumes
* that principal associated with this JVM has the appropriate
* permissions to access the target set of JVMs.
*
* @return Set - the Set of monitorable Java Virtual Machines
*/
public synchronized Set<Integer> activeVms() {
/*
* This method is synchronized because the Matcher object used by
* fileFilter is not safe for concurrent use, and this method is
* called by multiple threads. Before this method was synchronized,
* we'd see strange file names being matched by the matcher.
*/
Set<Integer> jvmSet = new HashSet<Integer>();
if (! tmpdir.isDirectory()) {
return jvmSet;
}
if (userName == null) {
/*
* get a list of all of the user temporary directories and
* iterate over the list to find any files within those directories.
*/
File[] dirs = tmpdir.listFiles(userFilter);
for (int i = 0 ; i < dirs.length; i ++) {
if (!dirs[i].isDirectory()) {
continue;
}
// get a list of files from the directory
File[] files = dirs[i].listFiles(fileFilter);
if (files != null) {
for (int j = 0; j < files.length; j++) {
if (files[j].isFile() && files[j].canRead()) {
jvmSet.add(new Integer(
PerfDataFile.getLocalVmId(files[j])));
}
}
}
}
} else {
/*
* Check if the user directory can be accessed. Any of these
* conditions may have asynchronously changed between subsequent
* calls to this method.
*/
// get the list of files from the specified user directory
File[] files = tmpdir.listFiles(fileFilter);
if (files != null) {
for (int j = 0; j < files.length; j++) {
if (files[j].isFile() && files[j].canRead()) {
jvmSet.add(new Integer(
PerfDataFile.getLocalVmId(files[j])));
}
}
}
}
// look for any 1.4.1 files
File[] files = tmpdir.listFiles(tmpFileFilter);
if (files != null) {
for (int j = 0; j < files.length; j++) {
if (files[j].isFile() && files[j].canRead()) {
jvmSet.add(new Integer(
PerfDataFile.getLocalVmId(files[j])));
}
}
}
return jvmSet;
}
}