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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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
* 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,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package com.sun.tools.visualvm.core.datasource;
import com.sun.tools.visualvm.core.datasupport.DataChangeEvent;
import com.sun.tools.visualvm.core.datasupport.DataChangeListener;
import com.sun.tools.visualvm.core.datasupport.Utils;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
* Default implementation of DataSourceProvider.
* DataSourceProviders can benefit from extending this class which implements
* managing created DataSource instances and firing the events to listeners.
*
* @author Jiri Sedlacek
*/
public class DataSourceProvider {
private static final boolean SUPPRESS_EXCEPTIONS_UI =
Boolean.getBoolean(DataSourceProvider.class.getName() + ".suppressExceptionsUI"); // NOI18N
private static final Logger LOGGER = Logger.getLogger(DataSourceProvider.class.getName());
private final Set<DataSource> dataSources = Collections.synchronizedSet(new HashSet());
private final Map<DataChangeListener<? extends DataSource>, Class<? extends DataSource>> listeners = new HashMap();
/**
* Creates new instance of DataSourceProvider.
*/
DataSourceProvider() {
}
/**
* Adds a DataChangeListener to listen for added/removed DataSources.
*
* @param <Y> any DataSource type.
* @param listener listener to be added.
* @param scope scope of DataSource types for which to get notifications.
*/
public final <Y extends DataSource> void addDataChangeListener(final DataChangeListener<Y> listener, final Class<Y> scope) {
DataSource.EVENT_QUEUE.post(new Runnable() {
public void run() {
if (listeners.containsKey(listener)) {
String msg = "Listener " + listener + " already registered"; // NOI18N
LOGGER.log(Level.SEVERE, msg, new UnsupportedOperationException(msg));
} else {
listeners.put(listener, scope);
fireCurrentState(listener);
}
}
});
}
/**
* Removes a DataChange listener.
*
* @param <Y> any DataSource type.
* @param listener listener to be removed.
*/
public final <Y extends DataSource> void removeDataChangeListener(final DataChangeListener<Y> listener) {
DataSource.EVENT_QUEUE.post(new Runnable() {
public void run() {
if (!listeners.containsKey(listener)) {
String msg = "Listener " + listener + " not registered"; // NOI18N
LOGGER.log(Level.SEVERE, msg, new UnsupportedOperationException(msg));
} else {
listeners.remove(listener);
}
}
});
}
/**
* Returns DataSources managed by this provider.
* @return DataSources managed by this provider.
*/
public final Set<DataSource> getDataSources() {
return new HashSet(Arrays.asList(dataSources.toArray()));
}
/**
* Returns DataSources of a certain type managed by this provider.
*
* @param <Y> any DataSource type.
* @param scope DataSource types to return.
* @return DataSources of a certain type managed by this provider.
*/
public final <Y extends DataSource> Set<Y> getDataSources(Class<Y> scope) {
return Utils.getFilteredSet(getDataSources(), scope);
}
/**
* Registers added DataSource into this provider.
*
* @param added added DataSource to register.
*/
protected final void registerDataSource(DataSource added) {
registerDataSources(Collections.singleton(added));
}
/**
* Registers added DataSources into this provider.
*
* @param added added DataSources to register.
*/
protected final void registerDataSources(final Set<? extends DataSource> added) {
DataSource.EVENT_QUEUE.post(new Runnable() {
public void run() {
if (!added.isEmpty())
registerDataSourcesImpl(checkAdded(added));
}
});
}
/**
* Unregisters removed DataSource from this provider.
*
* @param removed removed DataSource to unregister.
*/
protected final void unregisterDataSource(DataSource removed) {
unregisterDataSources(Collections.singleton(removed));
}
/**
* Unregisters removed DataSources from this provider.
*
* @param removed removed DataSources to unregister.
*/
protected final void unregisterDataSources(final Set<? extends DataSource> removed) {
DataSource.EVENT_QUEUE.post(new Runnable() {
public void run() {
if (!removed.isEmpty())
unregisterDataSourcesImpl(checkRemoved(removed));
}
});
}
/**
* Registers added DataSources into this provider and unregisters removed DataSources from this provider.
*
* @param added added DataSources to register.
* @param removed removed DataSources to unregister.
*/
protected final void changeDataSources(final Set<? extends DataSource> added, final Set<? extends DataSource> removed) {
DataSource.EVENT_QUEUE.post(new Runnable() {
public void run() {
if (!removed.isEmpty())
unregisterDataSourcesImpl(checkRemoved(removed));
if (!added.isEmpty())
registerDataSourcesImpl(checkAdded(added));
}
});
}
void registerDataSourcesImpl(Set<? extends DataSource> added) {
dataSources.addAll(added);
fireDataAdded(added);
}
void unregisterDataSourcesImpl(Set<? extends DataSource> removed) {
dataSources.removeAll(removed);
fireDataRemoved(removed);
}
private Set<? extends DataSource> checkAdded(Set<? extends DataSource> added) {
Set<? extends DataSource> uniqueAdded = new HashSet(added);
Iterator<? extends DataSource> it = uniqueAdded.iterator();
while(it.hasNext()) {
DataSource ds = it.next();
if (dataSources.contains(ds)) {
it.remove();
logUnsupportedOperation("DataSource already in repository: " + ds); // NOI18N
}
}
return uniqueAdded;
}
private Set<? extends DataSource> checkRemoved(Set<? extends DataSource> removed) {
Set<? extends DataSource> uniqueRemoved = new HashSet(removed);
Iterator<? extends DataSource> it = uniqueRemoved.iterator();
while(it.hasNext()) {
DataSource ds = it.next();
if (!dataSources.contains(ds)) {
it.remove();
logUnsupportedOperation("DataSource not in repository: " + ds); // NOI18N
}
}
return uniqueRemoved;
}
private static void logUnsupportedOperation(String msg) {
if (SUPPRESS_EXCEPTIONS_UI) LOGGER.severe(msg);
else LOGGER.log(Level.SEVERE, msg, new UnsupportedOperationException(msg));
}
private void fireCurrentState(DataChangeListener<? extends DataSource> listener) {
fireDataChanged(listener, null, null);
}
private void fireDataAdded(Set<? extends DataSource> added) {
fireDataChanged(added, Collections.EMPTY_SET);
}
private void fireDataRemoved(Set<? extends DataSource> removed) {
fireDataChanged(Collections.EMPTY_SET, removed);
}
private void fireDataChanged(Set<? extends DataSource> added, Set<? extends DataSource> removed) {
Set<DataChangeListener<? extends DataSource>> listenersSet = listeners.keySet();
for (DataChangeListener listener : listenersSet) fireDataChanged(listener, added, removed);
}
private void fireDataChanged(DataChangeListener<? extends DataSource> listener, Set<? extends DataSource> added, Set<? extends DataSource> removed) {
Class<? extends DataSource> filter = listeners.get(listener);
Set<? extends DataSource> filteredCurrent = Utils.getFilteredSet(dataSources, filter);
if (added == null && removed == null) {
DataChangeEvent event = new DataChangeEvent(filteredCurrent, filteredCurrent, null);
listener.dataChanged(event);
} else {
Set<? extends DataSource> filteredAdded = added != null ? Utils.getFilteredSet(added, filter) : Collections.EMPTY_SET;
Set<? extends DataSource> filteredRemoved = removed != null ? Utils.getFilteredSet(removed, filter) : Collections.EMPTY_SET;
if (!filteredAdded.isEmpty() || !filteredRemoved.isEmpty()) {
DataChangeEvent event = new DataChangeEvent(filteredCurrent, filteredAdded, filteredRemoved);
listener.dataChanged(event);
}
}
}
}