/*
* Copyright (C) 2016 Roman Leventov
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License.
*
* 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package net.openhft.chronicle.hash.impl;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.TreeMap;
import java.util.WeakHashMap;
final class ChronicleHashCloseOnExitHook {
private static final Logger LOG = LoggerFactory.getLogger(ChronicleHashCloseOnExitHook.class);
private static WeakHashMap<VanillaChronicleHash.Identity, Long> maps = new WeakHashMap<>();
private static long order = 0;
static {
Runtime.getRuntime().addShutdownHook(new Thread() {
@Override
public void run() {
closeAll();
}
});
}
static synchronized void add(VanillaChronicleHash hash) {
if (maps == null)
throw new IllegalStateException("Shutdown in progress");
maps.put(hash.identity, order++);
}
static synchronized void remove(VanillaChronicleHash hash) {
if (maps == null)
return; // we are already in shutdown
maps.remove(hash.identity);
}
private static void closeAll() {
try {
WeakHashMap<VanillaChronicleHash.Identity, Long> maps;
synchronized (ChronicleHashCloseOnExitHook.class) {
maps = ChronicleHashCloseOnExitHook.maps;
ChronicleHashCloseOnExitHook.maps = null;
}
TreeMap<Long, VanillaChronicleHash> orderedMaps = new TreeMap<>();
maps.forEach((identity, order) -> orderedMaps.put(order, identity.hash()));
// close later added maps first
orderedMaps.descendingMap().values().forEach(h -> {
try {
h.close();
} catch (Throwable throwable) {
try {
LOG.error("Error while closing " + h.toIdentityString() +
" during shutdown hook:", throwable);
} catch (Throwable t2) {
// This may occur if the log service has already been shut down. Try to fall
// back to printStackTrace().
throwable.addSuppressed(t2);
throwable.printStackTrace();
}
}
});
} catch (Throwable throwable) {
try {
LOG.error("Error while closing maps during shutdown hook:", throwable);
} catch (Throwable t2) {
throwable.addSuppressed(t2);
throwable.printStackTrace();
}
}
}
private ChronicleHashCloseOnExitHook() {}
}