/** {@inheritDoc} */
protected void getNewMonitors(Map<String, Monitor> map) throws MonitorException {
assert Thread.holdsLock(this);
int used = prologue.getUsed();
long modificationTime = prologue.getModificationTimeStamp();
if ((used > lastUsed) || (lastModificationTime > modificationTime)) {
lastUsed = used;
lastModificationTime = modificationTime;
Monitor monitor = getNextMonitorEntry();
while (monitor != null) {
String name = monitor.getName();
// guard against duplicate entries
if (!map.containsKey(name)) {
map.put(name, monitor);
/*
* insertedMonitors is null when called from pollFor()
* via buildMonitorMap(). Since we update insertedMonitors
* at the end of buildMonitorMap(), it's ok to skip the
* add here.
*/
if (insertedMonitors != null) {
insertedMonitors.add(monitor);
}
}
monitor = getNextMonitorEntry();
}
}
}
/** {@inheritDoc} */
protected MonitorStatus getMonitorStatus(Map<String, Monitor> map) throws MonitorException {
assert Thread.holdsLock(this);
assert insertedMonitors != null;
// load any new monitors
getNewMonitors(map);
// current implementation doesn't support deletion or reuse of entries
ArrayList removed = EMPTY_LIST;
ArrayList inserted = insertedMonitors;
insertedMonitors = new ArrayList<Monitor>();
return new MonitorStatus(inserted, removed);
}
/** {@inheritDoc} */
protected void buildMonitorMap(Map<String, Monitor> map) throws MonitorException {
assert Thread.holdsLock(this);
// start at the beginning of the buffer
buffer.rewind();
// create pseudo monitors
buildPseudoMonitors(map);
// position buffer to start of the data section
buffer.position(prologue.getSize());
nextEntry = buffer.position();
perfDataItem = 0;
int used = prologue.getUsed();
long modificationTime = prologue.getModificationTimeStamp();
Monitor m = getNextMonitorEntry();
while (m != null) {
map.put(m.getName(), m);
m = getNextMonitorEntry();
}
/*
* set the last modification data. These are set to the values
* recorded before parsing the data structure. This allows the
* the data structure to be modified while the Map is being built.
* The Map may contain more entries than indicated based on the
* time stamp, but this is handled by ignoring duplicate entries
* when the Map is updated in getNewMonitors().
*/
lastUsed = used;
lastModificationTime = modificationTime;
// synchronize with the target jvm
synchWithTarget(map);
// work around 1.4.2 counter inititization bugs
kludge(map);
insertedMonitors = new ArrayList<Monitor>(map.values());
}